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1.
Leone, Matthew Perry.
Understanding And Predicting Bagging Performance Through The Use Of CFD And DEM Simulations.
Degree: MS, Mechanical Engineering, 2015, University of North Dakota
URL: https://commons.und.edu/theses/1801
► This thesis will focus on rear discharge bagging performance for Rear Discharge Rear Collect (RDRC), Select Series Lawn & Garden tractors. The problem under…
(more)
▼ This thesis will focus on rear discharge bagging performance for Rear Discharge Rear Collect (RDRC), Select Series Lawn & Garden tractors. The problem under investigation pertains to adequately transporting cut grass from the mower deck to the dedicated hopper, without the plugging of the rear discharge chute or the deck mounted chute. The most problematic weather related factors are dew and rain, with the former being the most severe. Conditions creating this problem typically occur during the spring months and when the grass is at its healthiest state.
Field research and data have been collected to gain a better understanding of any and all factors involved as well as what factors can be controlled, what factors are uncontrollable, and what factors can be held constant. Computational Fluid Dynamics (
CFD) and Discrete Element Method (
DEM) simulations have been conducted to aid in geometry factor identification, field data validation, and field performance predictions.
During this study, a path was identified that leveraged the airflow generated by the mower blades through the rear discharge and mower deck chutes, in moving cut grass from the mower deck to the hopper. Further development of the chutes airflow has aided in increased bagging performance and decreased plugging during tough mowing conditions. Consequently, a better understanding of the
CFD and
DEM models result in improvements to future model analyses.
Advisors/Committee Members: Marcellin Zahui.
Subjects/Keywords: CFD; DEM; Simulations; Tractors
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APA (6th Edition):
Leone, M. P. (2015). Understanding And Predicting Bagging Performance Through The Use Of CFD And DEM Simulations. (Masters Thesis). University of North Dakota. Retrieved from https://commons.und.edu/theses/1801
Chicago Manual of Style (16th Edition):
Leone, Matthew Perry. “Understanding And Predicting Bagging Performance Through The Use Of CFD And DEM Simulations.” 2015. Masters Thesis, University of North Dakota. Accessed April 11, 2021.
https://commons.und.edu/theses/1801.
MLA Handbook (7th Edition):
Leone, Matthew Perry. “Understanding And Predicting Bagging Performance Through The Use Of CFD And DEM Simulations.” 2015. Web. 11 Apr 2021.
Vancouver:
Leone MP. Understanding And Predicting Bagging Performance Through The Use Of CFD And DEM Simulations. [Internet] [Masters thesis]. University of North Dakota; 2015. [cited 2021 Apr 11].
Available from: https://commons.und.edu/theses/1801.
Council of Science Editors:
Leone MP. Understanding And Predicting Bagging Performance Through The Use Of CFD And DEM Simulations. [Masters Thesis]. University of North Dakota; 2015. Available from: https://commons.und.edu/theses/1801

University of Texas – Austin
2.
-2681-7647.
Proppant transport in complex fracture networks.
Degree: PhD, Petroleum engineering, 2016, University of Texas – Austin
URL: http://hdl.handle.net/2152/45714
► Current hydraulic fracturing practice in unconventional resource development typically involves multiple fracturing stages, each consisting of the simultaneous creation of several fractures from a horizontal…
(more)
▼ Current hydraulic fracturing practice in unconventional resource development typically involves multiple fracturing stages, each consisting of the simultaneous creation of several fractures from a horizontal well. A large mass of proppant, often millions of pounds per well, is injected with the fluid to provide post-closure conductivity. Despite the large quantity of proppant used and its critical importance to well productivity, simple models are often applied to determine its placement in fractures. Propped or effective fracture lengths indicated by modeling may be 100 to 300% larger than the lengths inferred from production data. A common assumption is that the average proppant velocity due to pressure driven flow is equal to the average carrier fluid velocity, while the settling velocity calculation uses Stokes’ law. To more accurately determine the placement of proppant in a fracture, it is necessary to rigorously account for many effects not included in the above assumptions. In this study, the motion of particles flowing with a fluid between fracture walls has been simulated using a coupled computational fluid dynamics and discrete element method (
CFD-
DEM) that rigorously accounts for the both aspects of the problem. These simulations determine individual particle trajectories as particle to particle and particle to wall collisions occur and include the effect of fluid flow. The results show that the proppant concentration and the ratio of proppant diameter to fracture width govern the relative velocity of proppant and fluid. Proppant settling velocity has been examined for small fracture widths to delineate the effect of several independent variables, including concentration. Simulations demonstrate that larger concentration increases the average settling velocity, in apparent contrast with much of the available literature, which indicates that increased concentration reduces settling velocity. However, this is due to the absence of displacement driven counter current fluid flow. This demonstrates that proppant settling in a hydraulic fracture is more complex than usually considered. A proppant transport model developed from the results of the direct numerical simulations and existing correlations for particle settling velocity has been incorporated into a fully three-dimensional hydraulic fracturing simulator. This simulator couples fracture geomechanics with fluid flow and proppant transport considerations to enable the fracture geometry and proppant distribution to be determined rigorously. Two engineering fracture design parameters, injection rate and proppant diameter, have been varied to show the effect on proppant placement. This allows for an understanding of the relative importance of each and optimization of the treatment to a particular application. The presence of natural fractures in unconventional reservoirs can significantly contribute to well productivity. As proppant is transported along a hydraulic fracture, the presence of a dilated natural fracture forms a fluid accepting branch and may…
Advisors/Committee Members: Sharma, Mukul M. (advisor), Olson, Jon E (committee member), Bryant, Steven L (committee member), Lake, Larry L (committee member), Bonnecaze, Roger T (committee member).
Subjects/Keywords: CFD; DEM; Hydraulic fracturing
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
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APA (6th Edition):
-2681-7647. (2016). Proppant transport in complex fracture networks. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/45714
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Chicago Manual of Style (16th Edition):
-2681-7647. “Proppant transport in complex fracture networks.” 2016. Doctoral Dissertation, University of Texas – Austin. Accessed April 11, 2021.
http://hdl.handle.net/2152/45714.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
MLA Handbook (7th Edition):
-2681-7647. “Proppant transport in complex fracture networks.” 2016. Web. 11 Apr 2021.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Vancouver:
-2681-7647. Proppant transport in complex fracture networks. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2016. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/2152/45714.
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete
Council of Science Editors:
-2681-7647. Proppant transport in complex fracture networks. [Doctoral Dissertation]. University of Texas – Austin; 2016. Available from: http://hdl.handle.net/2152/45714
Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

University of New South Wales
3.
Liu, Ning.
Experimental and numerical investigations of particle breakage in grinding processes.
Degree: Materials Science & Engineering, 2011, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/51362
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10044/SOURCE1?view=true
► Grinding plays an important role in many industries and is still poorly understood because of complicated breakage behaviour of particles in the process. The lack…
(more)
▼ Grinding plays an important role in many industries and is still poorly understood because of complicated breakage behaviour of particles in the process. The lack of understanding of particle breakage has prevented the development of the fundamental understandings of the grinding process. This work investigated the breakage behaviours of particles under different grinding conditions. Physical experiments and numerical simulations were conducted in two different types of mills: a variable speed impact mill and a horizontal stirred mill. The effects of material characteristics and operation conditions were investigated. For the variable speed impact mill, it is shown that particle shape has a strong effect on the breakage behaviour. The irregular shape particles experience different crack mechanisms comparing with the regular shape particles, leading to the variation in breakage ratio. The breakage ratio increases significantly as the impact energy increases. Multiple impact tests show that the complete breakage can be reached at low impact energy after multiple impactions. Two material properties, resistance to fracture f_mat and threshold fracture energy W_(m,min) which describe the grindability of the materials, can be determined by fitting method. The results show that they are inversely proportional to each other. For the horizontal stirred mill, it is shown that the mill rotation speed plays a crucial role in particle breakage. The relationship between the grinding rate K_p and impact energy E_i in horizontal stirred mill has been analysed and the results show it follows the power law. The study of the relationship between grinding rate K_p and time indicates that the kinetics of the grinding process in horizontal stirred mill is in first order. The effect of increasing of the grinding media size shows a better grinding performance but the cost of power consumption is considerable. The
CFD-
DEM simulations of particle flow patterns reach an acceptable agreement with experimental results. Therefore, the model can be used to predict the variation of flow patterns of particles in the grinding process in horizontal stirred mill.
Advisors/Committee Members: Yang, Runyu, Materials Science & Engineering, Faculty of Science, UNSW.
Subjects/Keywords: CFD-DEM; Breakage; Grinding; Energy
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Liu, N. (2011). Experimental and numerical investigations of particle breakage in grinding processes. (Masters Thesis). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/51362 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10044/SOURCE1?view=true
Chicago Manual of Style (16th Edition):
Liu, Ning. “Experimental and numerical investigations of particle breakage in grinding processes.” 2011. Masters Thesis, University of New South Wales. Accessed April 11, 2021.
http://handle.unsw.edu.au/1959.4/51362 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10044/SOURCE1?view=true.
MLA Handbook (7th Edition):
Liu, Ning. “Experimental and numerical investigations of particle breakage in grinding processes.” 2011. Web. 11 Apr 2021.
Vancouver:
Liu N. Experimental and numerical investigations of particle breakage in grinding processes. [Internet] [Masters thesis]. University of New South Wales; 2011. [cited 2021 Apr 11].
Available from: http://handle.unsw.edu.au/1959.4/51362 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10044/SOURCE1?view=true.
Council of Science Editors:
Liu N. Experimental and numerical investigations of particle breakage in grinding processes. [Masters Thesis]. University of New South Wales; 2011. Available from: http://handle.unsw.edu.au/1959.4/51362 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10044/SOURCE1?view=true

University of New South Wales
4.
Mardus-Hall, Robert.
Multiphysics Coupling for PB-FHRs.
Degree: Mechanical & Manufacturing Engineering, 2020, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/67404
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:68105/SOURCE02?view=true
► Pebble-bed fuelled, molten salt-cooled nuclear reactors (PB-FHRs) involve interactions between a fluid coolant phase, solid particle fuel phase and neutron interactions enabling fission of nuclear…
(more)
▼ Pebble-bed fuelled, molten salt-cooled nuclear reactors (PB-FHRs) involve interactions between a fluid coolant phase, solid particle fuel phase and neutron interactions enabling fission of nuclear fuel for heat production. As these three aspects are highly interdependent, this work presents a three-way coupled methodology for simulation of PB-FHRs to provide a robust analysis tool for detailed analysis of such reactor designs.Computational fluid dynamics (
CFD) techniques are implemented for simulation of the coolant fluid’s flow and temperature fields. Discrete element methods (
DEM) are used to model individual pebble fuel elements present within the core, focusing on particle-particle interactions and structures formed within packed beds of mono-sized spheres. Modelling of the interaction between these two phases is realised through a two-way coupled methodology and open-source codes. Additional to the interaction of the fluid and pebble phases, consideration of the neutronic interactions resulting in nuclear heating of the fuel pebbles is included. The Monte Carlo neutron transport method is employed for determination of the fission rate distribution for PB-FHR geometries. Inclusion of the neutronics results within the
CFD and
DEM solvers, and vice versa, results in three-way coupled multiphysics simulations for PB-FHRs.This work has been built up over successively more complex simulations, starting with
CFD-
DEM replication of an isothermal pebble re-circulation experiment and culminating in the three-way coupled simulation of a true PB-FHR design. Additional analysis focusing on the neutronic behaviour of the PB-FHR geometry for various geometric and material property configurations is also presented. It was found that the multiplication factor of PB-FHRs with a free surface of pebbles within the core region are highly influenced on the shape of this free surface. The three-way coupling methodology was shown to provide detailed representations of PB-FHR geometries in a timely manner without the need for simplification of the geometry or material properties. This allowed for detailed analysis of coolant, fuel pebble and neutronic properties throughout the core region. The results obtained demonstrate the suitability for use as an accurate design tool.
Advisors/Committee Members: Yeoh, Guan, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW, Ho, Mark, ANSTO, Timchenko, Victoria, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW.
Subjects/Keywords: Neutronics; CFD; DEM; Nuclear
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mardus-Hall, R. (2020). Multiphysics Coupling for PB-FHRs. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/67404 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:68105/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Mardus-Hall, Robert. “Multiphysics Coupling for PB-FHRs.” 2020. Doctoral Dissertation, University of New South Wales. Accessed April 11, 2021.
http://handle.unsw.edu.au/1959.4/67404 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:68105/SOURCE02?view=true.
MLA Handbook (7th Edition):
Mardus-Hall, Robert. “Multiphysics Coupling for PB-FHRs.” 2020. Web. 11 Apr 2021.
Vancouver:
Mardus-Hall R. Multiphysics Coupling for PB-FHRs. [Internet] [Doctoral dissertation]. University of New South Wales; 2020. [cited 2021 Apr 11].
Available from: http://handle.unsw.edu.au/1959.4/67404 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:68105/SOURCE02?view=true.
Council of Science Editors:
Mardus-Hall R. Multiphysics Coupling for PB-FHRs. [Doctoral Dissertation]. University of New South Wales; 2020. Available from: http://handle.unsw.edu.au/1959.4/67404 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:68105/SOURCE02?view=true

University of New South Wales
5.
Zheng, Benny Weiguang.
Computer simulation of powder dispersion in commercial pharmaceutical inhalers.
Degree: Materials Science & Engineering, 2013, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/53072
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11758/SOURCE01?view=true
► This work presents a numerical study on two types of commercial inhalers, Aerolizer® andTurbuhaler® inhalers. A coupled Computational Fluid Dynamics (CFD) and DiscreteElement Method (DEM)…
(more)
▼ This work presents a numerical study on two types of commercial inhalers, Aerolizer® andTurbuhaler® inhalers. A coupled Computational Fluid Dynamics (
CFD) and DiscreteElement Method (
DEM) technique was adopted to simulate fluid flow and particles,respectively, for the Aerolizer® inhaler. The results showed that the shear stress ofturbulent flow had no visible effect on powder dispersion while the agglomerateagglomerateinteractions occurred only when the agglomerates were ejected from thecapsule. Between the agglomerates and the wall, many major impactions occurredresulting in fragmentation of agglomerates into large pieces without generating many fineparticles. The subsequent impaction with the inhaler grid also contributed to an increase inFPF (amount of fine particles below 5 μm in the aerosol). It was observed that the inhalerwas more efficient in terms of FPF with increasing airflow rate but FPF decreased at ahigher flow of 130 L/min due to larger deposition inside the inhaler.The study on the Turbuhaler® inhaler was approached using
CFD coupled with DiscretePhase Modelling (DPM). The effects of key variables associated with airflow rates andparticle sizes were investigated. It was found that smaller particles moved faster in theinhaler and experienced more impactions. However their impact energy was low. Largerparticles, while having large impact energy, were more inclined to be traveling slowerinside the inhaler. FPF generated from the inhaler increased with increasing airflow ratesbut powder deposition also increased with larger air flowrate.This study has highlighted an important role of numerical modelling techniques such asCFD-
DEM to provide further insight into the effect of airflow inside DPIs and thesubsequent effect on particles travelling inside the inhaler. This allows a rational basis forfuture improvement of inhaler devices.
Advisors/Committee Members: Yang, Runyu, Materials Science & Engineering, Faculty of Science, UNSW.
Subjects/Keywords: CFD; DPI; Turbuhaler; DEM; Modelling; Inhaler
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zheng, B. W. (2013). Computer simulation of powder dispersion in commercial pharmaceutical inhalers. (Masters Thesis). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/53072 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11758/SOURCE01?view=true
Chicago Manual of Style (16th Edition):
Zheng, Benny Weiguang. “Computer simulation of powder dispersion in commercial pharmaceutical inhalers.” 2013. Masters Thesis, University of New South Wales. Accessed April 11, 2021.
http://handle.unsw.edu.au/1959.4/53072 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11758/SOURCE01?view=true.
MLA Handbook (7th Edition):
Zheng, Benny Weiguang. “Computer simulation of powder dispersion in commercial pharmaceutical inhalers.” 2013. Web. 11 Apr 2021.
Vancouver:
Zheng BW. Computer simulation of powder dispersion in commercial pharmaceutical inhalers. [Internet] [Masters thesis]. University of New South Wales; 2013. [cited 2021 Apr 11].
Available from: http://handle.unsw.edu.au/1959.4/53072 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11758/SOURCE01?view=true.
Council of Science Editors:
Zheng BW. Computer simulation of powder dispersion in commercial pharmaceutical inhalers. [Masters Thesis]. University of New South Wales; 2013. Available from: http://handle.unsw.edu.au/1959.4/53072 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11758/SOURCE01?view=true

University of New South Wales
6.
Wahyudi, Hadi.
Three-dimensional particle scale modeling of heat transfer in fluidized beds.
Degree: Materials Science & Engineering, 2014, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/53180
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11873/SOURCE02?view=true
► Heat transfer between particle-fluid media and solid surfaces has wide applications in industries such as power plant, steel heat treatment, and chemical processes. One of…
(more)
▼ Heat transfer between particle-fluid media and solid surfaces has wide applications in industries such as power plant, steel heat treatment, and chemical processes. One of the important applications which is still being intensively investigated is the heat transfer between bed and surfaces in fluidized bed combustors. In contrast to single-phase systems where the fundamental transport phenomena are well established, the mechanisms of heat transfer in particle-fluid media are still in development. This thesis represents an effort in this area.A mathematical model of heat transfer at individual particle scale in computational fluid dynamics (CFD) – discrete element method (DEM) framework is developed to study heat transfer between bed of particles and the solid surface in three dimensional bubbling and circulating fluidized beds. The model is then validated both qualitatively and quantitatively. The results suggest that the model is capable of predicting both gas-solids flows and heat transfer performance in simple and complex geometries of fluidized beds. The proposed mathematical model is then applied to study the effects of some key parameters on the heat transfer coefficient between bed of particles and the solid surfaces (tube surfaces or wall) in bubbling and circulating fluidized beds. The results confirm the effects of some parameters such as superficial gas velocity, thermo-physical properties of particles, and solids inventory. Furthermore, the results show that in fluidized beds, tube configurations (inline and staggered arrangements) have no significant differences. In addition, the analysis in terms of governing heat transfer modes shows that in fluidized beds under atmospheric condition, the maximum heat transfer coefficient is due to the interplay between tube-fluid convection and tube-particle conduction while in pressurized fluidized beds, it is due to the drastic decrease of tube-particle conduction. In circulating fluidized beds, the heat transfer between bed of particles and riser wall can also be enhanced if the sliding friction coefficient of particles is very low. Moreover, it is found that the low heat rate from or to particles at region near the riser wall is attributed to the individual particles in dense phase and the high heat rate is attributed to the individual particles in dilute phase.
Subjects/Keywords: CFD-DEM; Heat transfer; Fluidized bed
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wahyudi, H. (2014). Three-dimensional particle scale modeling of heat transfer in fluidized beds. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/53180 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11873/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Wahyudi, Hadi. “Three-dimensional particle scale modeling of heat transfer in fluidized beds.” 2014. Doctoral Dissertation, University of New South Wales. Accessed April 11, 2021.
http://handle.unsw.edu.au/1959.4/53180 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11873/SOURCE02?view=true.
MLA Handbook (7th Edition):
Wahyudi, Hadi. “Three-dimensional particle scale modeling of heat transfer in fluidized beds.” 2014. Web. 11 Apr 2021.
Vancouver:
Wahyudi H. Three-dimensional particle scale modeling of heat transfer in fluidized beds. [Internet] [Doctoral dissertation]. University of New South Wales; 2014. [cited 2021 Apr 11].
Available from: http://handle.unsw.edu.au/1959.4/53180 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11873/SOURCE02?view=true.
Council of Science Editors:
Wahyudi H. Three-dimensional particle scale modeling of heat transfer in fluidized beds. [Doctoral Dissertation]. University of New South Wales; 2014. Available from: http://handle.unsw.edu.au/1959.4/53180 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11873/SOURCE02?view=true

University of New South Wales
7.
Miao, Zhen.
CFD-DEM Simulation of Raceway Formation in a Blast Furnace.
Degree: Materials Science & Engineering, 2014, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/53948
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12659/SOURCE02?view=true
► Blast furnace is one of the most significant technologies in ironmaking industry. Particularly, in the lower part of blast furnace, the raceway is considered to…
(more)
▼ Blast furnace is one of the most significant technologies in ironmaking industry. Particularly, in the lower part of blast furnace, the raceway is considered to be one of the most important zones where complex chemistry and physical reactions occur. In order to achieve higher efficient and stable operating situation, investigations on raceway region have become a useful and critical method to achieve a deeper understanding of blast furnace, since the stability and shape of raceway influence the total production.In this thesis, a 2-D slot model on the basis of combined discrete element method (
DEM) and computational fluid dynamics (
CFD) (
DEM-
CFD) model has been used to carry out numerical study of complex particle and gas two phase flows in blast furnace raceway region. In the
DEM-
CFD coupling approach, the motions of single particles are modeled by
DEM approach as discrete phase, and the gas flow field is considered as continuum phase, modeled by
CFD approach. By using
DEM-
CFD approach, the effect of some variables on raceway such as bed weight, gas velocity and coke combustion can be achieved. In addition, with the development of computational technology, this method can be used to simulate the blast furnace in actual size and generate rich microscopic information such as flow structure and force structure. Thus, the
DEM-
CFD approach is used in this thesis to investigate the effect of some parameters on raceway size and shape. The calculated results indicate that these parameters have obvious effects on raceway size and shape. Three kinds of typical raceways are witnessed from calculated results: anti-clockwise raceway, clockwise raceway and plumelike raceway. This phenomenon is examined by investigating the particle flow pattern, particle velocity, porosity, normal contact force and gas flow at raceway region. The observation of two contrary circulating gas vortexes located upon and below tuyere during raceway formation has a good agreement with experiments carried out in cold models. If the simulation condition has a positive effect on the increment of one of the two gas vortexes, this gas vortex will become the main circulating gas flow and determine the circulating direction. The plumelike raceway is always generated for the cases with loaded packed bed which is formed by increasing the density of particles.
Advisors/Committee Members: zongyan, zhou, Materials Science & Engineering, Faculty of Science, UNSW.
Subjects/Keywords: DEM-CFD; Blast furnace; Raceway; Formation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Miao, Z. (2014). CFD-DEM Simulation of Raceway Formation in a Blast Furnace. (Masters Thesis). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/53948 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12659/SOURCE02?view=true
Chicago Manual of Style (16th Edition):
Miao, Zhen. “CFD-DEM Simulation of Raceway Formation in a Blast Furnace.” 2014. Masters Thesis, University of New South Wales. Accessed April 11, 2021.
http://handle.unsw.edu.au/1959.4/53948 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12659/SOURCE02?view=true.
MLA Handbook (7th Edition):
Miao, Zhen. “CFD-DEM Simulation of Raceway Formation in a Blast Furnace.” 2014. Web. 11 Apr 2021.
Vancouver:
Miao Z. CFD-DEM Simulation of Raceway Formation in a Blast Furnace. [Internet] [Masters thesis]. University of New South Wales; 2014. [cited 2021 Apr 11].
Available from: http://handle.unsw.edu.au/1959.4/53948 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12659/SOURCE02?view=true.
Council of Science Editors:
Miao Z. CFD-DEM Simulation of Raceway Formation in a Blast Furnace. [Masters Thesis]. University of New South Wales; 2014. Available from: http://handle.unsw.edu.au/1959.4/53948 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:12659/SOURCE02?view=true

University of Newcastle
8.
Ge, Linhan.
Numerical investigation of particle dynamics in the presence of unconfined and confined gas bubbles.
Degree: PhD, 2019, University of Newcastle
URL: http://hdl.handle.net/1959.13/1411257
► Research Doctorate - Doctor of Philosophy (PhD)
The thesis aims to improve the fundamental understanding of particle dynamics in the flotation process and gas-liquid-solid (GLS)…
(more)
▼ Research Doctorate - Doctor of Philosophy (PhD)
The thesis aims to improve the fundamental understanding of particle dynamics in the flotation process and gas-liquid-solid (GLS) Taylor flow microreactors. In both systems, bubbles play an essential role in determining the overall performance by influencing the dynamics of other phases. In the flotation process, small and unconfined bubbles are used as carriers to capture hydrophobic particles while large and confined Taylor bubbles are introduced to microreactors to suspend and transport particles. These two processes involve complex phase dynamics and interactions with a wide spectrum of spatial and temporal scales. The difficulties in experimentally investigating the two systems lead to a demand for the establishment of efficient and accurate computational frameworks for modelling and design of these systems. In this study, Computational Fluid Dynamics and Discrete Element Method were coupled (CFD-DEM) to analyse the particle-bubble interactions in the flotation process. Specifically, CFD was used to resolve the fluid flow surrounding a rigid spherical bubble, while DEM is used to treat the particle phase. In contrast, the Volume of Fluid, which can account for bubble deformation, is coupled to DEM (VOF-DEM) to simulate a GLS Taylor flow microreactor. Although CFD/VOF-DEM coupling has been widely applied for the modelling of multiphase flow systems, it is still a challenge to select a single length scale to resolve the continuous phase and the dispersed phase simultaneously in a coupling model. Conflicts arise when there is a need to resolve fluid features at different length scales such as for systems in the presence of bubbles and particles with large size differences. In this work, a special coupling scheme was proposed to resolve the conflicts to realise the so-called multi-scale modelling. The CFD-DEM model proposed was firstly applied to simulate the interaction and approach of a particle swarm to a stationary bubble for various solid fractions (0.01 ≤ εp ≤ 0.25) and bubble Reynolds numbers (50 ≤ Re>sub>b</sub> ≤ 200). It was observed that the collision efficiency decreased with increasing solid fraction until achieving a plateau value. This plateau was attributed to the increase in the lateral expansion of the swarm and the increase in particle velocities. The former effect decreased the number of collisions by interception, while the latter increased the inertial effects. However, when the bubble Reynolds number increased, the particle swarm did not have enough time to accelerate or deform before reaching the bubble, and thus, the collision efficiency became insensitive to the solid fraction. Following the study of the particle-bubble collision, the particle dynamics in the bubble wake for Reb = 100, 160, 220 and 280 were investigated. The results showed that as the bubble Reynolds Number increased, the discharge rate, i.e. the rate of particles escaped from the bubble wake, increased. The maximum number of particles that can…
Advisors/Committee Members: University of Newcastle. Faculty of Engineering & Built Environment, School of Engineering.
Subjects/Keywords: particle; bubble; flotation; Taylor flow; microreactor; CFD-DEM; VOF-DEM
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❌
APA ·
Chicago ·
MLA ·
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CSE |
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APA (6th Edition):
Ge, L. (2019). Numerical investigation of particle dynamics in the presence of unconfined and confined gas bubbles. (Doctoral Dissertation). University of Newcastle. Retrieved from http://hdl.handle.net/1959.13/1411257
Chicago Manual of Style (16th Edition):
Ge, Linhan. “Numerical investigation of particle dynamics in the presence of unconfined and confined gas bubbles.” 2019. Doctoral Dissertation, University of Newcastle. Accessed April 11, 2021.
http://hdl.handle.net/1959.13/1411257.
MLA Handbook (7th Edition):
Ge, Linhan. “Numerical investigation of particle dynamics in the presence of unconfined and confined gas bubbles.” 2019. Web. 11 Apr 2021.
Vancouver:
Ge L. Numerical investigation of particle dynamics in the presence of unconfined and confined gas bubbles. [Internet] [Doctoral dissertation]. University of Newcastle; 2019. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/1959.13/1411257.
Council of Science Editors:
Ge L. Numerical investigation of particle dynamics in the presence of unconfined and confined gas bubbles. [Doctoral Dissertation]. University of Newcastle; 2019. Available from: http://hdl.handle.net/1959.13/1411257

Université de Lorraine
9.
Maione, Riccardo.
Modélisation d’un système de pyrogazéification de la biomasse : Modeling of an original process of thermochemical conversion of biomasses.
Degree: Docteur es, Génie des procédés et des produits, 2017, Université de Lorraine
URL: http://www.theses.fr/2017LORR0088
► Ce travail s’inscrit dans le projet LORVER, soutenu par la Région Grand Est et le FEDER. Il est destiné à créer une filière de production…
(more)
▼ Ce travail s’inscrit dans le projet LORVER, soutenu par la Région Grand Est et le FEDER. Il est destiné à créer une filière de production de biomasse végétale non alimentaire par valorisation de sites dégradés et de sous-produits industriels, en Lorraine. Un des procédés de valorisation de la biomasse produite est un procédé thermochimique de pyro-gazéification qui générerait de la chaleur et de l’électricité. Ce procédé, développé par SEA Marconi, se compose de trois réacteurs différents : un tambour tournant, pour la pyrolyse de particules de bois, la chaleur étant amenée par des billes d’acier chauffées ; un réacteur à vis sans fin pour l’oxydation du char qui permet de réchauffer les billes d’acier ; un réacteur de craquage des goudrons. L’objectif de cette thèse est de réaliser des modèles qui puissent permettre d’avoir une prédiction adaptée du comportement du système. Des modèles 3D du type DEM et CFD-DEM ont été conçus pour la modélisation des phénomènes qui interviennent dans le système. Les paramètres du modèle DEM ont été calibrés dans un tambour tournant de laboratoire. Pour le réacteur de pyrolyse, la simulation DEM a permis de prédire de façon satisfaisante la ségrégation pour des mélanges de billes d’acier et de particules non sphériques de bois, et de concevoir un modèle thermique et chimique 1D, sur lequel une étude de sensibilité a été effectuée. Un modèle CFD-DEM a été codé et validé sur un rhéomètre granulaire, permettant la simulation du réacteur d’oxydation partielle du char, qui n’a pas pu être réalisé dans le cadre de cette thèse
This work is part of the LORVER project, funded by Grand Est Région and FEDER. It aims to create a non-food biomass production chain by using and upgrading brownfields and industrial by-products in Lorraine. One possible valorization process of the produced biomass is a thermochemical pyro-gasification process that would generate heat and electricity. This process, developed by SEA Marconi, involves three different reactors: a rotating drum, for the pyrolysis of wood particles, the heat required being brought by hot steel balls; an Auger for partial oxidation of the char that allows heating the steel balls; a reactor for tar cracking. The aim of this thesis is to develop models that can predict the behavior of the system. 3D models based on DEM or CFD - DEM were designed for the modeling of phenomena involved in the system. The DEM model parameters were first calibrated in a rotating drum. The DEM simulation was able to predict in a satisfactory manner segregation between steel balls and non-spherical wood particles; it also helped to design a 1D thermal and chemical model, on which a sensitivity study has been done. A CFD - DEM model has been coded and validated on a granular rheometer allowing the simulation of the char oxidation reactor, even if this simulation was not possible during the PhD
Advisors/Committee Members: Wild, Gabriel (thesis director), Mauviel, Guillain (thesis director).
Subjects/Keywords: Pyrolyse; Tambour tournant; Modélisation; DEM; Ségrégation; CFD; Pyrolysis; Rotary kiln; Modeling; DEM; CFD-DEM; 662.88; 662.65
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Maione, R. (2017). Modélisation d’un système de pyrogazéification de la biomasse : Modeling of an original process of thermochemical conversion of biomasses. (Doctoral Dissertation). Université de Lorraine. Retrieved from http://www.theses.fr/2017LORR0088
Chicago Manual of Style (16th Edition):
Maione, Riccardo. “Modélisation d’un système de pyrogazéification de la biomasse : Modeling of an original process of thermochemical conversion of biomasses.” 2017. Doctoral Dissertation, Université de Lorraine. Accessed April 11, 2021.
http://www.theses.fr/2017LORR0088.
MLA Handbook (7th Edition):
Maione, Riccardo. “Modélisation d’un système de pyrogazéification de la biomasse : Modeling of an original process of thermochemical conversion of biomasses.” 2017. Web. 11 Apr 2021.
Vancouver:
Maione R. Modélisation d’un système de pyrogazéification de la biomasse : Modeling of an original process of thermochemical conversion of biomasses. [Internet] [Doctoral dissertation]. Université de Lorraine; 2017. [cited 2021 Apr 11].
Available from: http://www.theses.fr/2017LORR0088.
Council of Science Editors:
Maione R. Modélisation d’un système de pyrogazéification de la biomasse : Modeling of an original process of thermochemical conversion of biomasses. [Doctoral Dissertation]. Université de Lorraine; 2017. Available from: http://www.theses.fr/2017LORR0088

Brno University of Technology
10.
Slowik, Roman.
CFD modelování toku partikulárních látek v rotační peci: CFD modelling of granular flow in rotary kiln.
Degree: 2020, Brno University of Technology
URL: http://hdl.handle.net/11012/191836
► This work deals with modeling the flow of particulate matter in rotary kilns. For this purpose, a combined CFD and Discrete Element Method (DEM) model…
(more)
▼ This work deals with modeling the flow of particulate matter in rotary kilns. For this purpose, a combined
CFD and Discrete Element Method (
DEM) model was used. Using Ansys Fluent software, several simulations were performed in order to determine the mean residence time and movement of the material in the rotary drum dryer. Results of the computational model were used to develop a regression model of the mean residence time and compared to the values as given by empirical equations. Furthermore, a simplified sensitivity analysis was performed for the selected input parameters of the model such as the stiffness constant, air mass flow rate and the particle size.
Advisors/Committee Members: Juřena, Tomáš (advisor), Vondál, Jiří (referee).
Subjects/Keywords: Rotační sušárna; rotační pec; CFD; DEM; zdržná doba; Rotary dryer; rotary kiln; CFD; DEM; residence time
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Slowik, R. (2020). CFD modelování toku partikulárních látek v rotační peci: CFD modelling of granular flow in rotary kiln. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/191836
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Slowik, Roman. “CFD modelování toku partikulárních látek v rotační peci: CFD modelling of granular flow in rotary kiln.” 2020. Thesis, Brno University of Technology. Accessed April 11, 2021.
http://hdl.handle.net/11012/191836.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Slowik, Roman. “CFD modelování toku partikulárních látek v rotační peci: CFD modelling of granular flow in rotary kiln.” 2020. Web. 11 Apr 2021.
Vancouver:
Slowik R. CFD modelování toku partikulárních látek v rotační peci: CFD modelling of granular flow in rotary kiln. [Internet] [Thesis]. Brno University of Technology; 2020. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/11012/191836.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Slowik R. CFD modelování toku partikulárních látek v rotační peci: CFD modelling of granular flow in rotary kiln. [Thesis]. Brno University of Technology; 2020. Available from: http://hdl.handle.net/11012/191836
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
11.
Marechal, Ewen.
Etude du colmatage des systèmes carburant de turboréacteurs par des suspensions denses de particules de glace : Clogging of jet-engine fuel systems by dense suspensions of ice particles.
Degree: Docteur es, Génie industriel, 2016, Paris, ENSAM
URL: http://www.theses.fr/2016ENAM0002
► Dans certaines conditions de température et de débit, l’eau naturellement présente dans le kérosène va givrer l’intérieur des conduites du système carburant avion. Ces dépôts…
(more)
▼ Dans certaines conditions de température et de débit, l’eau naturellement présente dans le kérosène va givrer l’intérieur des conduites du système carburant avion. Ces dépôts peuvent libérer des particules de glace qui sont entrainées par l’écoulement, et provoquent le colmatage des équipements hydrauliques situés en aval. Ce phénomène fut mis en évidence suite à l’accident d’un Boeing 777 en 2008, aussi sa compréhension est un enjeu important pour les acteurs de l’industrie aéronautique. Un dispositif a été spécialement conçu pour reproduire cette menace de façon quantifiée. De l’eau est atomisée dans un écoulement à basse température, puis cristallise pour former une suspension qui vient colmater différentes cibles perforées. Les températures, débits et pertes de charge sont mesurées, et le phénomène est filmé par une caméra haute fréquence. Un modèle a été réalisé à partir de cesobservations, complétées par des données issues de la littérature et de retoursd’expérience. Pour la phase fluide, les équations de Navier-Stokes incompressibles sont résolues par une approche volumes finis. Le couplage pression-vitesse est obtenu par l’algorithme SIMPLE et l’ordre élevé au moyen de la méthode MLS. La phase solide est simulée par éléments discrets. L’interaction fluide-particules repose sur une approche de type milieu poreux. Un code CFD-DEM parallèle a été développé, et les premières simulations d’écoulement en milieu granulaire sont en bon agrément avec des résultats expérimentaux.
Water, which exists naturally in jet-engine fuel, may freeze within theaircraft fuel pipes under certain temperatures and flow rates. The ice particles released by these deposits are entrained by the flow, and clog the hydraulics downstream. The understanding of this phenomenon, highlighted by the crash of a Boeing 777 in 2008, is an important issue for the aviation industry. Therefore a device has been designed to reproduce this threat in a controlled and quantified way. Water is atomized in low temperature jet-engine fuel and the droplets crystallize. The resulting slurry clogs different kinds of perforated targets. Temperatures, flow rates and pressure drops are monitored, and the phenomenon is filmed by a high frequency camera. A model was constructed based on these observations and data from literature and feedbacks. For the fluid phase, the incompressible Navier-Stokes equations are solved within a finite volume framework. The pressure-velocity coupling is achieved using the SIMPLE algorithm and high order of accuracy thanks to the MLS method. The solid phase is simulated using discrete elements. The fluid-particle interaction is based on a porous medium approach. A CFD-DEM parallel code has been developed to run the model. The first simulations of flow through granular media are in good agreement with experimental results.
Advisors/Committee Members: Bakir, Farid (thesis director), Khelladi, Sofiane (thesis director), Ravelet, Florent (thesis director).
Subjects/Keywords: Colmatage; Cfd-Dem; Glace; Simple; Mls; Volumes finis; Clogging; Cfd-Dem; Ice; Simple; Mls; Finite Volumes
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Marechal, E. (2016). Etude du colmatage des systèmes carburant de turboréacteurs par des suspensions denses de particules de glace : Clogging of jet-engine fuel systems by dense suspensions of ice particles. (Doctoral Dissertation). Paris, ENSAM. Retrieved from http://www.theses.fr/2016ENAM0002
Chicago Manual of Style (16th Edition):
Marechal, Ewen. “Etude du colmatage des systèmes carburant de turboréacteurs par des suspensions denses de particules de glace : Clogging of jet-engine fuel systems by dense suspensions of ice particles.” 2016. Doctoral Dissertation, Paris, ENSAM. Accessed April 11, 2021.
http://www.theses.fr/2016ENAM0002.
MLA Handbook (7th Edition):
Marechal, Ewen. “Etude du colmatage des systèmes carburant de turboréacteurs par des suspensions denses de particules de glace : Clogging of jet-engine fuel systems by dense suspensions of ice particles.” 2016. Web. 11 Apr 2021.
Vancouver:
Marechal E. Etude du colmatage des systèmes carburant de turboréacteurs par des suspensions denses de particules de glace : Clogging of jet-engine fuel systems by dense suspensions of ice particles. [Internet] [Doctoral dissertation]. Paris, ENSAM; 2016. [cited 2021 Apr 11].
Available from: http://www.theses.fr/2016ENAM0002.
Council of Science Editors:
Marechal E. Etude du colmatage des systèmes carburant de turboréacteurs par des suspensions denses de particules de glace : Clogging of jet-engine fuel systems by dense suspensions of ice particles. [Doctoral Dissertation]. Paris, ENSAM; 2016. Available from: http://www.theses.fr/2016ENAM0002

The Ohio State University
12.
Gong, Yiwen.
Toward Better Understandings of Unconventional Reservoirs -
Rock Mechanical Properties and Hydraulic Fracture
Perspectives.
Degree: PhD, Chemical Engineering, 2020, The Ohio State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1605633687308252
► The advancements of hydraulic fracturing techniques ensure the improved fracture surface areas that are open to fluids flow. The induced microcracks accelerate the fluid communications…
(more)
▼ The advancements of hydraulic fracturing techniques
ensure the improved fracture surface areas that are open to fluids
flow. The induced microcracks accelerate the fluid communications
between fractures and the fracture adjacent rock matrix at fracture
surface. In brittle rocks, the generated fracture network puzzles
engineers since the induced hydraulic fractures and activated
pre-existing fractures challenge the stimulated reservoir volume
(SRV) characterizations. Furthermore, the necessary engineered
justifications of each stage due to lateral heterogeneity of the
reservoir and the stress shadow effect (in-situ stress increase
along the wellbore) even introduce another level of complexity of
the effective fracture drainage complexity. Simultaneous fracture
growth becomes difficult, resulting in variations of fracture half
lengths, within a stage, and among stages. The failure planes of
the rock, from mode I, mode II and the combination of them, are not
smooth and parallel; instead, they are usually associated with
certain surface roughness and non-planar morphology, which in turn
inhibit the ideal Poiseuille flow in the fracture. As a result, the
fundamental studies of non-planar and rough complex fracture paths
to the proppant transport are essentially inevitable.To gain better
understanding of the fracture network and the geomechanical aspects
that form the complex fracture network, the objective of this work
is firstly to quantitatively measure the rock damage from the
induced microcracks at the adjacent matrix of the hydraulic
fracture; we will then investigate the rock geomechanical
properties which essentially dominant the fracture generation using
machine learning approaches with cross-disciplinary data sources,
including well logs, petrophysical properties, and rock
microstructures information. Lastly, we will probe proppant
transport characteristics in bifurcated fracture system. To achieve
the aforementioned adjectives, this dissertation is structured into
two major parts: the microstructure diagnosis of fractured tight
rocks and geomechanical rock property estimations beyond the
traditional approach as the first part and the proppant transport
considering the induced microfracture/bifurcated fractures as the
second part. To be more specific, the microstructure analysis is
achieved by SEM image analysis while the geomechanical study is
conducted optimizing the data usage from machine learning
techniques. The second major part is to build the complex fracture
network modeling by including non-planarity, and secondary
fractures and tertiary fractures in the computational fluid
dynamics modeling frame (Eulerian-Eulerian) in the field scale as
well as computational fluid dynamics – discrete element method
coupling frame (Eulerian- Lagrangian) in the flow-unit scale,
respectively. The proppant transport loss passing the bifurcated
fractures are evaluated.
Advisors/Committee Members: El-Monier, Ilham (Advisor), Tomasko, David (Committee Co-Chair).
Subjects/Keywords: Chemical Engineering; Petroleum Engineering; Proppant transport; machine learning; rock geomechanical properties; CFD; CFD-DEM
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Gong, Y. (2020). Toward Better Understandings of Unconventional Reservoirs -
Rock Mechanical Properties and Hydraulic Fracture
Perspectives. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1605633687308252
Chicago Manual of Style (16th Edition):
Gong, Yiwen. “Toward Better Understandings of Unconventional Reservoirs -
Rock Mechanical Properties and Hydraulic Fracture
Perspectives.” 2020. Doctoral Dissertation, The Ohio State University. Accessed April 11, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1605633687308252.
MLA Handbook (7th Edition):
Gong, Yiwen. “Toward Better Understandings of Unconventional Reservoirs -
Rock Mechanical Properties and Hydraulic Fracture
Perspectives.” 2020. Web. 11 Apr 2021.
Vancouver:
Gong Y. Toward Better Understandings of Unconventional Reservoirs -
Rock Mechanical Properties and Hydraulic Fracture
Perspectives. [Internet] [Doctoral dissertation]. The Ohio State University; 2020. [cited 2021 Apr 11].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1605633687308252.
Council of Science Editors:
Gong Y. Toward Better Understandings of Unconventional Reservoirs -
Rock Mechanical Properties and Hydraulic Fracture
Perspectives. [Doctoral Dissertation]. The Ohio State University; 2020. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1605633687308252

Queensland University of Technology
13.
Kuruneru, Sahan Trushad Wickramasooriya.
Numerical modelling of particle deposition in idealized porous channels.
Degree: 2015, Queensland University of Technology
URL: https://eprints.qut.edu.au/90555/
► This project provides a steppingstone to comprehend the mechanisms that govern particulate fouling in metal foam heat exchangers. The method is based on development of…
(more)
▼ This project provides a steppingstone to comprehend the mechanisms that govern particulate fouling in metal foam heat exchangers. The method is based on development of an advanced Computational Fluid Dynamics model in addition to performing analytical validation. This novel method allows an engineer to better optimize heat exchanger designs, thereby mitigating fouling, reducing energy consumption caused by fouling, economize capital expenditure on heat exchanger maintenance, and reduce operation downtime. The robust model leads to the establishment of an alternative heat exchanger configuration that has lower pressure drop and particulate deposition propensity.
Subjects/Keywords: Metal Foam; Heat Exchanger; CFD-DEM; fouling; particle deposition
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kuruneru, S. T. W. (2015). Numerical modelling of particle deposition in idealized porous channels. (Thesis). Queensland University of Technology. Retrieved from https://eprints.qut.edu.au/90555/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kuruneru, Sahan Trushad Wickramasooriya. “Numerical modelling of particle deposition in idealized porous channels.” 2015. Thesis, Queensland University of Technology. Accessed April 11, 2021.
https://eprints.qut.edu.au/90555/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kuruneru, Sahan Trushad Wickramasooriya. “Numerical modelling of particle deposition in idealized porous channels.” 2015. Web. 11 Apr 2021.
Vancouver:
Kuruneru STW. Numerical modelling of particle deposition in idealized porous channels. [Internet] [Thesis]. Queensland University of Technology; 2015. [cited 2021 Apr 11].
Available from: https://eprints.qut.edu.au/90555/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kuruneru STW. Numerical modelling of particle deposition in idealized porous channels. [Thesis]. Queensland University of Technology; 2015. Available from: https://eprints.qut.edu.au/90555/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
14.
Aragall Tersa, Roger.
Improvements of cuttings transport models through physical experiments and numerical investigations of solid-liquid transport.
Degree: 2016, Technische Universität Dortmund
URL: https://doi.org/10.21268/20160527-114433
;
https://nbn-resolving.org/urn:nbn:de:gbv:104-1126737
;
https://dokumente.ub.tu-clausthal.de/receive/clausthal_mods_00000201
;
https://dokumente.ub.tu-clausthal.de/servlets/MCRFileNodeServlet/Document_derivate_00000339/Db112673.pdf
► Wellbore drilling has experienced an increase in complexity due to the interest in reaching targets situated in High Pressure-High Temperature (HPHT) environments or construct- ing…
(more)
▼ Wellbore drilling has experienced an increase in complexity due to the interest in reaching
targets situated in High Pressure-High Temperature (HPHT) environments or construct-
ing large sections of the well with high deviations from verticality. Established models
for selecting operational flow rates or drilling fluid rheology and density are based on
empirical correlations. These are only applicable for well defined ranges of conditions and
for stationary assumptions not given in complex wellbores. In the last two decades, more
flexible and transient models founded on causal mechanisms responsible of the system’s
behavior are finding wider application. These rely on an accurate understanding of the
phenomena taking place within the wellbore. High resolution numerical models can be
used to increase this understanding. However, experimental data are still needed for their
validation. This thesis provides such experimental data and evaluates high resolution
numerical models able to predict cuttings transport relevant phenomena at the wellbore
diameter scale.
In the experimental part of this thesis, a solid-liquid vertical flow-loop designed and con-
structed to generate experimental data for validation is presented. The setup consists of
a 64 mm diameter and 2,000 mm length pipe, medicinal white oil and and glass spher-
ical particles with diameters ranging from 2 to 6 mm providing a system with physical
phenomena similar to the one found in cuttings transport. The particle image velocime-
try (PIV) and particle tracking velocimetry (PTV) techniques are implemented to obtain
liquid and particles velocity profiles as well as particle position histograms of solid-liquid
mono- and bidisperse flows. This is accomplished through refractive index matching of
the dispersed phase, the continuous phase and the conduct material. Results point out
the relevancy of the lift force in configuring particles distribution across the pipe section.
This force creates concentration accumulations at specific radial positions. Furthermore,
a significant momentum transfer between the considered particles is observed in bidisperse
systems.
The computational part of the thesis considers the implementation of the two-fluid method
and the discrete particle model (DPM) to simulate the experimental system and prove
their validity for the prediction of cuttings transport relevant problems. The two-fluid
method shows good agreement with experiments performed with monodisperse systems
and supplies an explanation for the concentration accumulations observed in the experi-
ments. However, this lacks predictive capacity when polydisperse systems are investigated.
On the other hand, the DPM model implemented here is able to reproduce bidisperse ex-
perimental results up to 3% concentrations. For higher ones, advanced models considering
particle collisions in viscous fluids should be included. The DPM model is selected as the
best alternative for cuttings transport problems. A sensitivity analysis focused on the ef-
…
Advisors/Committee Members: Brenner, Gunther.
Subjects/Keywords: Abschlussarbeit; doctoral thesis; ddc:620; PIV/PTV; CFD-DEM; Bohrkleintransport
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to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Aragall Tersa, R. (2016). Improvements of cuttings transport models through physical experiments and numerical investigations of solid-liquid transport. (Thesis). Technische Universität Dortmund. Retrieved from https://doi.org/10.21268/20160527-114433 ; https://nbn-resolving.org/urn:nbn:de:gbv:104-1126737 ; https://dokumente.ub.tu-clausthal.de/receive/clausthal_mods_00000201 ; https://dokumente.ub.tu-clausthal.de/servlets/MCRFileNodeServlet/Document_derivate_00000339/Db112673.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Aragall Tersa, Roger. “Improvements of cuttings transport models through physical experiments and numerical investigations of solid-liquid transport.” 2016. Thesis, Technische Universität Dortmund. Accessed April 11, 2021.
https://doi.org/10.21268/20160527-114433 ; https://nbn-resolving.org/urn:nbn:de:gbv:104-1126737 ; https://dokumente.ub.tu-clausthal.de/receive/clausthal_mods_00000201 ; https://dokumente.ub.tu-clausthal.de/servlets/MCRFileNodeServlet/Document_derivate_00000339/Db112673.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Aragall Tersa, Roger. “Improvements of cuttings transport models through physical experiments and numerical investigations of solid-liquid transport.” 2016. Web. 11 Apr 2021.
Vancouver:
Aragall Tersa R. Improvements of cuttings transport models through physical experiments and numerical investigations of solid-liquid transport. [Internet] [Thesis]. Technische Universität Dortmund; 2016. [cited 2021 Apr 11].
Available from: https://doi.org/10.21268/20160527-114433 ; https://nbn-resolving.org/urn:nbn:de:gbv:104-1126737 ; https://dokumente.ub.tu-clausthal.de/receive/clausthal_mods_00000201 ; https://dokumente.ub.tu-clausthal.de/servlets/MCRFileNodeServlet/Document_derivate_00000339/Db112673.pdf.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Aragall Tersa R. Improvements of cuttings transport models through physical experiments and numerical investigations of solid-liquid transport. [Thesis]. Technische Universität Dortmund; 2016. Available from: https://doi.org/10.21268/20160527-114433 ; https://nbn-resolving.org/urn:nbn:de:gbv:104-1126737 ; https://dokumente.ub.tu-clausthal.de/receive/clausthal_mods_00000201 ; https://dokumente.ub.tu-clausthal.de/servlets/MCRFileNodeServlet/Document_derivate_00000339/Db112673.pdf
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology
15.
Mehmood, Junaid (author).
Study of Rheological Behaviour of Spherocylindrical Particle Suspension via CFD-DEM: Formulation of Stress-Closure for Industrial Fluidized Bed Simulation.
Degree: 2018, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:6e8e2b5c-7577-4a29-8085-99c74c604325
► While colloidal suspensions of non-spherical particles have been studied relatively extensively, granular suspensions of non-spherical particles are rarely studied. The rheological behaviour of elongated granular…
(more)
▼ While colloidal suspensions of non-spherical particles have been studied relatively extensively, granular suspensions of non-spherical particles are rarely studied. The rheological behaviour of elongated granular particles is therefore not well known. This thesis deals with suspensions of rod-like particles of aspect ratio 4 subjected to shear flow in a low-density, highly viscous Newtonian fluid. CFD-DEM simulations for a periodic shear box have been performed for a pre-estimated range of shear rates and volume fractions. Dependence of rheological properties like shear stresses, relative viscosity, granular temperature, pressure and normal stress differences on the shear rate and volume fraction have been studied. These granular rods show shear thickening behaviour. The spherocylindrical particle suspensions experience less collisional stresses than spherical particles due to preferred particle alignment in the shear direction. Herschel and Bulkley [1] model is used to fit the collisional stress data. Two different regimes have been identified for granular suspension based on the flow index. Interestingly, a relatively large range of shear rates and associated stress can be expressed in the form of a simple equation based on Broughton and Squires [2] model. This stress closure will further be used in more coarse grid models like MP-PIC which can simulate an industrial fluidized bed reactors of non-spherical particles.
Chemical Engineering
Advisors/Committee Members: Padding, Johan (mentor), Mahajan, Vinay (mentor), Eral, Burak (graduation committee), van Ommen, Ruud (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Discrete Element Method; CFD-DEM Coupling; Spherocylindrical Particle; Rheology
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APA ·
Chicago ·
MLA ·
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CSE |
Export
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APA (6th Edition):
Mehmood, J. (. (2018). Study of Rheological Behaviour of Spherocylindrical Particle Suspension via CFD-DEM: Formulation of Stress-Closure for Industrial Fluidized Bed Simulation. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:6e8e2b5c-7577-4a29-8085-99c74c604325
Chicago Manual of Style (16th Edition):
Mehmood, Junaid (author). “Study of Rheological Behaviour of Spherocylindrical Particle Suspension via CFD-DEM: Formulation of Stress-Closure for Industrial Fluidized Bed Simulation.” 2018. Masters Thesis, Delft University of Technology. Accessed April 11, 2021.
http://resolver.tudelft.nl/uuid:6e8e2b5c-7577-4a29-8085-99c74c604325.
MLA Handbook (7th Edition):
Mehmood, Junaid (author). “Study of Rheological Behaviour of Spherocylindrical Particle Suspension via CFD-DEM: Formulation of Stress-Closure for Industrial Fluidized Bed Simulation.” 2018. Web. 11 Apr 2021.
Vancouver:
Mehmood J(. Study of Rheological Behaviour of Spherocylindrical Particle Suspension via CFD-DEM: Formulation of Stress-Closure for Industrial Fluidized Bed Simulation. [Internet] [Masters thesis]. Delft University of Technology; 2018. [cited 2021 Apr 11].
Available from: http://resolver.tudelft.nl/uuid:6e8e2b5c-7577-4a29-8085-99c74c604325.
Council of Science Editors:
Mehmood J(. Study of Rheological Behaviour of Spherocylindrical Particle Suspension via CFD-DEM: Formulation of Stress-Closure for Industrial Fluidized Bed Simulation. [Masters Thesis]. Delft University of Technology; 2018. Available from: http://resolver.tudelft.nl/uuid:6e8e2b5c-7577-4a29-8085-99c74c604325

Delft University of Technology
16.
Fantin, Davide (author).
CFD-DEM Coupling for Systems of Fluid and Non-Spherical Particles.
Degree: 2018, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:6ddce0bf-dc00-4f7a-bb07-040b9851a8e8
► The models for CFD-DEM coupling for fluid-particles simulations are explored. Emphasis is given to the implementation of a multisphere approach to handle non-spherical particles and…
(more)
▼ The models for CFD-DEM coupling for fluid-particles simulations are explored. Emphasis is given to the implementation of a multisphere approach to handle non-spherical particles and to improvements of current features available in software packages. Some tests and applications are proposed.
COSSE (Computer Simulations for Science and Engineering)
Applied Mathematics
Advisors/Committee Members: Vuik, Kees (mentor), Heemink, Arnold (graduation committee), Bos, F. (mentor), Delft University of Technology (degree granting institution).
Subjects/Keywords: CFD-DEM Coupling; Multisphere; Discrete Element Method; OpenFOAM
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Fantin, D. (. (2018). CFD-DEM Coupling for Systems of Fluid and Non-Spherical Particles. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:6ddce0bf-dc00-4f7a-bb07-040b9851a8e8
Chicago Manual of Style (16th Edition):
Fantin, Davide (author). “CFD-DEM Coupling for Systems of Fluid and Non-Spherical Particles.” 2018. Masters Thesis, Delft University of Technology. Accessed April 11, 2021.
http://resolver.tudelft.nl/uuid:6ddce0bf-dc00-4f7a-bb07-040b9851a8e8.
MLA Handbook (7th Edition):
Fantin, Davide (author). “CFD-DEM Coupling for Systems of Fluid and Non-Spherical Particles.” 2018. Web. 11 Apr 2021.
Vancouver:
Fantin D(. CFD-DEM Coupling for Systems of Fluid and Non-Spherical Particles. [Internet] [Masters thesis]. Delft University of Technology; 2018. [cited 2021 Apr 11].
Available from: http://resolver.tudelft.nl/uuid:6ddce0bf-dc00-4f7a-bb07-040b9851a8e8.
Council of Science Editors:
Fantin D(. CFD-DEM Coupling for Systems of Fluid and Non-Spherical Particles. [Masters Thesis]. Delft University of Technology; 2018. Available from: http://resolver.tudelft.nl/uuid:6ddce0bf-dc00-4f7a-bb07-040b9851a8e8

University of Adelaide
17.
Farivar, Foad.
Multiscale modelling of a pharmaceutical fluidized bed coating process.
Degree: 2020, University of Adelaide
URL: http://hdl.handle.net/2440/124258
► Fluidized Bed (FB) spray coating is a critical process for the manufacture of solid dosage forms in pharmaceutical industry. In this process a coating film…
(more)
▼ Fluidized Bed (FB) spray coating is a critical process for the manufacture of solid dosage forms in pharmaceutical industry. In this process a coating film is applied to the core particles as successive layers. Depending on the application, the coating film can be an active pharmaceutical ingredient (API) or non-API materials and the core particles can be spherical or non-spherical. In both applications, the uniformity of the applied film on the core particles is of paramount importance to control release of the amount of API in the body and the variation of coating mass in the final products needs to be strictly controlled to satisfy FDA regulations. Therefore, a deep understanding of the FB coating process, especially for non-spherical core particles is essential for ensuring a high quality of the final products. One of the main challenges in these unit operations is that monitoring inside the fluid bed with non-invasive methods is very difficult. Therefore, experimentation for dense multi-phase FBs is not easily implemented. To overcome the limitations of experimental methods a model-based approach can be useful to understand, predict and optimize the process. In this thesis, a multi-scale mathematical model is used to study the dynamics of a pharmaceutical FB coater. At the first stage, a discrete element model (
DEM) is developed to study the behaviour of both spherical and non-spherical particles (at a scale of millimetre). The in-house developed
DEM code is validated against experimental data for cylinder-like fibrous particles in different flow regimes. It has been shown that particle- particle interactions play an important role in the movement and orientation of free- falling cylinder-like particles. In the second part of the thesis, a computational fluid dynamic (
CFD) based code coupled with the developed
DEM code is used to study the dynamics of FB systems. It has been revealed that the representation method for non-spherical particles in
DEM influences the performance of the code and the accuracy of results. In addition, a general guideline for representation of cylindrical particles using the multi-sphere method is provided and the effect of the number of spheres and the multi-sphere formation methods on the dynamics of fluidized beds is investigated. Finally, a discrete droplet model (DDM) at micrometre level is developed to model the spray droplets. The DDM-
CFD-
DEM code is applied to simulate a lab-scale FB Wurster spray coating process. The coating mass uniformity for both spherical particle and non-spherical particles in the FB coater is evaluated. The results of this study offer great insights into the coating process of both spherical and non-spherical particles and provide guidelines to optimize and scale-up the process in fluidized bed coaters.
Advisors/Committee Members: Zhang, Hu (advisor), Tian, Zhao Feng (advisor), Gupte, Anshul (advisor), School of Chemical Engineering and Advanced Materials (school).
Subjects/Keywords: Simulation; multi-scale modelling; CFD-DEM; fluidized bed
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Farivar, F. (2020). Multiscale modelling of a pharmaceutical fluidized bed coating process. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/124258
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Farivar, Foad. “Multiscale modelling of a pharmaceutical fluidized bed coating process.” 2020. Thesis, University of Adelaide. Accessed April 11, 2021.
http://hdl.handle.net/2440/124258.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Farivar, Foad. “Multiscale modelling of a pharmaceutical fluidized bed coating process.” 2020. Web. 11 Apr 2021.
Vancouver:
Farivar F. Multiscale modelling of a pharmaceutical fluidized bed coating process. [Internet] [Thesis]. University of Adelaide; 2020. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/2440/124258.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Farivar F. Multiscale modelling of a pharmaceutical fluidized bed coating process. [Thesis]. University of Adelaide; 2020. Available from: http://hdl.handle.net/2440/124258
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Virginia Tech
18.
Sun, Rui.
Particle-Resolving Simulations of Dune Migration: Novel Algorithms and Physical Insights.
Degree: PhD, Aerospace Engineering, 2017, Virginia Tech
URL: http://hdl.handle.net/10919/78260
► Sediment transport is ubiquitous in aquatic environments, and the study of sediment transport is important for both engineering and environmental reasons. However, the understanding and…
(more)
▼ Sediment transport is ubiquitous in aquatic environments, and the study of sediment transport is important for both engineering and environmental reasons. However, the understanding and prediction of sediment transport are hindered by its complex dynamics and regimes. In this dissertation, the open-source solver SediFoam is developed for high-fidelity particle-resolving simulations of various sediment transport problems based on open-source solvers OpenFOAM and LAMMPS. OpenFOAM is a
CFD toolbox that can perform three-dimensional flow simulations on unstructured mesh; LAMMPS is a massively parallel
DEM solver for molecular dynamics. To enable the particle-resolving simulation of sediment transport on an arbitrary mesh, a diffusion-based algorithm is used in SediFoam to obtain the averaged Eulerian fields from discrete particle data. The parallel interface is also implemented for the communication of the two open-source solvers. Extensive numerical simulations are performed to validate the capability of SediFoam in the modeling of sediment transport problems. The predictions of various sediment transport regimes, including `flat bed in motion', `small dune' and `vortex dune', are in good agreement of with the experimental results and those obtained by using interface resolved simulations. The capability of the solver in the simulation of sediment transport in the oscillatory boundary layer is also demonstrated. Moreover, this well-validated high-fidelity simulation tool has been used to probe the physics of particle dynamics in self-generated bedforms in various hydraulic conditions. The results obtained by using SediFoam not only bridge the gaps in the experimental results but also help improve the engineering practice in the understanding of sediment transport. By using the particle-resolving simulation results and the insights generated therein, the closure terms in the two-fluid models or hydro-morphodynamic models can be improved, which can contribute to the numerical modeling of sediment transport in engineering scales.
Advisors/Committee Members: Xiao, Heng (committeechair), Liu, Yang (committee member), Wang, Kevin Guanyuan (committee member), Irish, Jennifer L. (committee member), Paterson, Eric G. (committee member).
Subjects/Keywords: Sediment Transport; CFD – DEM; Particle-Resolving Simulations; Multiphase Flow; Dune Migration
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sun, R. (2017). Particle-Resolving Simulations of Dune Migration: Novel Algorithms and Physical Insights. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/78260
Chicago Manual of Style (16th Edition):
Sun, Rui. “Particle-Resolving Simulations of Dune Migration: Novel Algorithms and Physical Insights.” 2017. Doctoral Dissertation, Virginia Tech. Accessed April 11, 2021.
http://hdl.handle.net/10919/78260.
MLA Handbook (7th Edition):
Sun, Rui. “Particle-Resolving Simulations of Dune Migration: Novel Algorithms and Physical Insights.” 2017. Web. 11 Apr 2021.
Vancouver:
Sun R. Particle-Resolving Simulations of Dune Migration: Novel Algorithms and Physical Insights. [Internet] [Doctoral dissertation]. Virginia Tech; 2017. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/10919/78260.
Council of Science Editors:
Sun R. Particle-Resolving Simulations of Dune Migration: Novel Algorithms and Physical Insights. [Doctoral Dissertation]. Virginia Tech; 2017. Available from: http://hdl.handle.net/10919/78260
19.
Hariharan, Anand.
Large scale simulation of particle coating using coupled CFD-DEM
.
Degree: Chalmers tekniska högskola / Institutionen för mekanik och maritima vetenskaper, 2020, Chalmers University of Technology
URL: http://hdl.handle.net/20.500.12380/301791
► Spouted fluidized beds are widely used for particle coating because of its excellent mixing rates and favorable heat and mass transfer characteristics. The combination of…
(more)
▼ Spouted fluidized beds are widely used for particle coating because of its excellent mixing rates and
favorable heat and mass transfer characteristics. The combination of Computational Fluid Dynamics
(CFD) and the Discrete Element Method (DEM) has previously been employed for simulation of
the complex phenomena of such processes. However, simulating a fluidized bed on a large scale
with DEM requires exceptional computational power as all the interactions between the particles
are fully resolved. In addition, simulating the spray droplets further increases the computational
demand. Accordingly, coupled DEM and CFD simulations with a well resolved spray have typically
been limited to system sizes from a few thousand up to much less than a million particles.
The goal of the current thesis was to perform spray coating simulations on systems with more than 1
million particles, including a Lagrangian spray phase and a well resolved fluid. The thesis is carried
out using the DEM-CFD solver IPS FluidizationTM developed at Fraunhofer Chalmers Centre. The
solver is based on an in-house DEM code and the in-house immersed boundary CFD code IBOFlowR
.
Due to heavy use of the Graphical Processing Unit (GPU), the code allows simulating a large number
of particles and a well resolved fluid on a standard desktop computer.
In the first part of the thesis, single spout simulations are carried out to validate the coupled solver.
The simulations show excellent agreement with the experimental data available in the open literature.
Further, 1D studies are conducted for verifying the heat transfer model. The numerical predictions are
shown to be accurate based on comparisons with analytical 1D models. Finally, large scale simulations
including the spray and drying are conducted on a Wurster bed system with both the particles and
the spray considered in a Lagrangian sense. The simulations show the versatility of the tool and the
possibility to e.g. characterize the particle coating thickness in terms of the original particle size, as
well as it proves applicability to cases with more than 1 million particles.
Subjects/Keywords: CFD;
DEM;
particle coating;
Wurster bed;
fluidization;
GPU
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hariharan, A. (2020). Large scale simulation of particle coating using coupled CFD-DEM
. (Thesis). Chalmers University of Technology. Retrieved from http://hdl.handle.net/20.500.12380/301791
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Hariharan, Anand. “Large scale simulation of particle coating using coupled CFD-DEM
.” 2020. Thesis, Chalmers University of Technology. Accessed April 11, 2021.
http://hdl.handle.net/20.500.12380/301791.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Hariharan, Anand. “Large scale simulation of particle coating using coupled CFD-DEM
.” 2020. Web. 11 Apr 2021.
Vancouver:
Hariharan A. Large scale simulation of particle coating using coupled CFD-DEM
. [Internet] [Thesis]. Chalmers University of Technology; 2020. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/20.500.12380/301791.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Hariharan A. Large scale simulation of particle coating using coupled CFD-DEM
. [Thesis]. Chalmers University of Technology; 2020. Available from: http://hdl.handle.net/20.500.12380/301791
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
20.
Silva, Álisson Renan Stochero da.
Modelagem experimental e computacional DEM-CFD da fluidização de partículas Geldart-D com formato irregular.
Degree: 2019, Universidade do Vale do Rio dos Sinos; Programa de Pós-Graduação em Engenharia Mecânica; Unisinos; Brasil; Escola Politécnica
URL: http://www.repositorio.jesuita.org.br/handle/UNISINOS/8918
► Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2019-10-25T17:00:22Z No. of bitstreams: 1 Álisson Renan Stochero da Silva_.pdf: 8154562 bytes, checksum: 80d052348aa0d99e851fcf3c4baaea8c (MD5)
Made available…
(more)
▼ Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2019-10-25T17:00:22Z No. of bitstreams: 1 Álisson Renan Stochero da Silva_.pdf: 8154562 bytes, checksum: 80d052348aa0d99e851fcf3c4baaea8c (MD5)
Made available in DSpace on 2019-10-25T17:00:22Z (GMT). No. of bitstreams: 1 Álisson Renan Stochero da Silva_.pdf: 8154562 bytes, checksum: 80d052348aa0d99e851fcf3c4baaea8c (MD5) Previous issue date: 2019-04-12
CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Reatores de leito fluidizado encontram diversas aplicações em processos de conversão termo-energética. A preferência por este tipo de sistema se deve às características de altas taxas de transferência de calor e massa, entre o sólido particulado que compõe o leito e o agente fluidizante. A simulação computacional tridimensional destes sistemas é capaz de fornecer dados locais como campos de velocidade, pressão, temperatura e concentração de espécies químicas, o que não é
possível de se obter em modelos zero-dimensionais ou experimentalmente, com a tecnologia hoje disponível. Dentre os modelos computacionais existentes, um dos mais recentes e atrativos, devido à sua precisão, é o que utiliza o acoplamento do Método dos Elementos Discretos (DEM) com a Dinâmica dos Fluidos Computacional (CFD). Nesta abordagem, o movimento da fase granular é computado diretamente pelo DEM, enquanto o fluido é tratado como um meio contínuo, por um modelo CFD. A interação entre as fases fluido e granular é realizada por um algoritmo de acoplamento. Com o objetivo de criar um modelo computacional DEM-CFD para a fluidização de partículas de polipropileno, realizou-se a caracterização física do material particulado, determinando a massa específica real e de carga, o diâmetro médio, a esfericidade, e os ângulos de repouso e de atrito interno (drawdown). As partículas foram classificadas como do tipo Geldart-D, e durante sua fluidização apresentaram comportamento de jorro. Os
coeficientes de interação partícula-partícula e partícula-parede, como atrito estático, atrito dinâmico, coeficiente de restituição e resistência ao rolamento, parâmetros de entrada do DEM, foram obtidos via planejamento de experimentos e técnica de otimização. Observou-se que dentre estes parâmetros, o que possui maior efeito sobre os resultados é a resistência ao rolamento. As fluidizações em escala de laboratório forneceram os valores de referência para a velocidade de jorro mínimo, a máxima queda de pressão no leito e a queda de pressão na condição de jorro mínimo. Durante as simulações do reator, foi avaliado o refino de malha computacional, bem como, o refino de parede, utilizando quatro malhas com tamanho da célula, baseado no diâmetro das partículas, na razão de 2x, 3x e 5x, respectivamente. As simulações DEM-CFD da fluidização corroboram com os resultados experimentais, com um erro de 1,88% para U_jm, 0,66% para 〖∆P〗_MÁX e 0,77% para 〖∆P〗_jm, sendo uma poderosa ferramenta
para estudos desta espécie.
Fluidized bed reactors find many applications in thermo-energy conversion…
Advisors/Committee Members: http://lattes.cnpq.br/8732272690265023, Zinani, lávia Schwarz Franceschini.
Subjects/Keywords: ACCNPQ::Engenharias::Engenharia Mecânica; Fluidização; DEM-CFD; Escoamento multifásico; Simulação computacional; Geldart-D; Fluidization; DEM-CFD; Multiphase flow; Computational Simulation; Geldart-D
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Silva, . R. S. d. (2019). Modelagem experimental e computacional DEM-CFD da fluidização de partículas Geldart-D com formato irregular. (Masters Thesis). Universidade do Vale do Rio dos Sinos; Programa de Pós-Graduação em Engenharia Mecânica; Unisinos; Brasil; Escola Politécnica. Retrieved from http://www.repositorio.jesuita.org.br/handle/UNISINOS/8918
Chicago Manual of Style (16th Edition):
Silva, Álisson Renan Stochero da. “Modelagem experimental e computacional DEM-CFD da fluidização de partículas Geldart-D com formato irregular.” 2019. Masters Thesis, Universidade do Vale do Rio dos Sinos; Programa de Pós-Graduação em Engenharia Mecânica; Unisinos; Brasil; Escola Politécnica. Accessed April 11, 2021.
http://www.repositorio.jesuita.org.br/handle/UNISINOS/8918.
MLA Handbook (7th Edition):
Silva, Álisson Renan Stochero da. “Modelagem experimental e computacional DEM-CFD da fluidização de partículas Geldart-D com formato irregular.” 2019. Web. 11 Apr 2021.
Vancouver:
Silva RSd. Modelagem experimental e computacional DEM-CFD da fluidização de partículas Geldart-D com formato irregular. [Internet] [Masters thesis]. Universidade do Vale do Rio dos Sinos; Programa de Pós-Graduação em Engenharia Mecânica; Unisinos; Brasil; Escola Politécnica; 2019. [cited 2021 Apr 11].
Available from: http://www.repositorio.jesuita.org.br/handle/UNISINOS/8918.
Council of Science Editors:
Silva RSd. Modelagem experimental e computacional DEM-CFD da fluidização de partículas Geldart-D com formato irregular. [Masters Thesis]. Universidade do Vale do Rio dos Sinos; Programa de Pós-Graduação em Engenharia Mecânica; Unisinos; Brasil; Escola Politécnica; 2019. Available from: http://www.repositorio.jesuita.org.br/handle/UNISINOS/8918

UCLA
21.
Van Lew, Jon Thomas.
On Thermal Characterization of Breeder Pebble Beds with Microscale Numerical Modeling of Thermofluid and Pebble-pebble Interactions.
Degree: Mechanical Engineering, 2016, UCLA
URL: http://www.escholarship.org/uc/item/332285gp
► Lithium ceramic pebble beds are a proposed form for tritium breeding volumes in fusion reactors. In application, the beds will endure high volumetric energy deposition…
(more)
▼ Lithium ceramic pebble beds are a proposed form for tritium breeding volumes in fusion reactors. In application, the beds will endure high volumetric energy deposition densities but must maintain within relatively-narrow prescribed temperature operating windows for efficient tritium release, while also providing continued transport of high quality heat into coolants for power production. The ceramic pebble beds, as non-cohesive granular material, exist with metastable packing structures defined by the local equilibrium between normal forces and static friction force chains in the assembly. Differential rates of heating and thermal expansion coefficients between ceramic pebble beds and their structural container induce stresses in the bed volume. If sufficiently large, the stresses overcome the local equilibrium of inter-pebble forces and irreversibly compel the pebble bed into a new metastable packing state. Transport of heat from pebble bed to coolant structure is divided between contact conductance between pebbles in the ensemble and convection with a helium purge gas filling the interporous voids. Thus thermal characteristics of pebble beds are intimately linked with its mechanical ones. As a consequence, predictive models of solid breeder heat transfer characteristics must contend with both flowing interporous fluid as well as transitory packing structures and the changing modes of heat transfer they present. To provide such predictive modeling, microscale numerical models were developed allowing investigation of thermal transport in pebble beds operating in environmental conditions relevant to planned fusion reactors. Specific effort was made to apply the predictive models toward simulating pebble bed thermomechanical responses to the fault condition of crushed individual pebbles.In this work, the thermal discrete element method (DEM) has been used to model forces and heat transfer between individual pebbles in assemblies. Pebble interaction with slow-moving, interstitial helium purge gas is accomplished by means of two coupling approaches. First, the fluid is considered with a volume-averaged computational fluid dynamic (CFD) method. Volume-averaged models of helium are computationally efficient and provide an overall view of helium influence on heat transfer in solid breeder pebble beds. Second, the lattice-Boltzmann method (LBM) is employed to gain insight into complete fluid flow patterns and conjugate heat transfer. The lattice-Boltzmann method is well-suited to modeling complex porous structures (such as packed beds) due to its inherent parallelizability and simple application of solid-fluid interface boundary conditions on structured grids. Several open-source codes have been used as platforms for launching the numerical experiments. The codes provided basic numerical frameworks for, e.g. time integration, particle tracking, mesh decomposition, and streaming/colliding operators. However to apply the numeric codes on the unique environment of fusion pebble beds, the following contributions to the code were…
Subjects/Keywords: Engineering; coupled CFD-DEM; discrete element method; granular heat transfer; lithium ceramic; numerical modeling
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Van Lew, J. T. (2016). On Thermal Characterization of Breeder Pebble Beds with Microscale Numerical Modeling of Thermofluid and Pebble-pebble Interactions. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/332285gp
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Van Lew, Jon Thomas. “On Thermal Characterization of Breeder Pebble Beds with Microscale Numerical Modeling of Thermofluid and Pebble-pebble Interactions.” 2016. Thesis, UCLA. Accessed April 11, 2021.
http://www.escholarship.org/uc/item/332285gp.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Van Lew, Jon Thomas. “On Thermal Characterization of Breeder Pebble Beds with Microscale Numerical Modeling of Thermofluid and Pebble-pebble Interactions.” 2016. Web. 11 Apr 2021.
Vancouver:
Van Lew JT. On Thermal Characterization of Breeder Pebble Beds with Microscale Numerical Modeling of Thermofluid and Pebble-pebble Interactions. [Internet] [Thesis]. UCLA; 2016. [cited 2021 Apr 11].
Available from: http://www.escholarship.org/uc/item/332285gp.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Van Lew JT. On Thermal Characterization of Breeder Pebble Beds with Microscale Numerical Modeling of Thermofluid and Pebble-pebble Interactions. [Thesis]. UCLA; 2016. Available from: http://www.escholarship.org/uc/item/332285gp
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
22.
Gupta, Prashant.
Verification and validation of a DEM-CFD model and multiscale modelling of cohesive fluidization regimes.
Degree: PhD, 2015, University of Edinburgh
URL: http://hdl.handle.net/1842/10449
► Fluidization of solid particles using gas flow is an important process in chemical and pharmaceutical industries. The dynamics of fluidisation are intricately related to particle…
(more)
▼ Fluidization of solid particles using gas flow is an important process in chemical and pharmaceutical industries. The dynamics of fluidisation are intricately related to particle scale physics. Fluid-particle interactions dominate gas-solid fluidization behaviour for particles with average size and density greater than 10-4 m and 103 kg/m3, respectively, classified as Geldart B and D particles. Inter-particle forces, such as cohesion, play an increasingly important role in the fluidization dynamics of smaller particles, which are classified as Geldart A and C. In particular, interesting fluidization regimes have been noticed for weakly cohesive Geldart A particles, exhibiting a window of uniform fluidization before the onset of bubbling behaviour. Despite widespread industrial interests, the fundamental understanding of the mechanisms that underlie these fluidization regimes is poor. The present study aims to improve the understanding of fluidization dynamics of Geldart A regimes using numerical simulations. A DEM-CFD model was employed to capture the widely separated spatial and temporal scales associated with fluidization behaviour. The model couples the locally averaged Navier-Stokes equation for fluid with a discrete description of the particles. The methodology and its computer implementation are verified and validated to assess the extent of fluidization physics that it is able to capture. Verification cases check the implementation of the inter-phase momentum transfer term, drag model implementation and pressure-velocity coupling. The test cases are employed in order to cover a wide range of flow conditions. Robust validation tests for complex fluidization phenomena such as bubbling, spouting and bidisperse beds have been conducted to assess the predictive capabilities of the DEM-CFD solver. The simulation results for time and spatially averaged fluidziation behaviour are compared to experimental measurements obtained from the literature, and are shown to have capture fluidization physics qualitatively. Robust features of bubbling fluidization, such as minimum fluidization velocity, frequency of pressure drop fluctuations, segregation rates and solid circulation patterns were captured. Furthermore, the DEM-CFD model is critically assessed in terms of model conceptualization and parameter estimation, including those for drag closures, particle-wall boundary conditions, bed height and particle shape effects. The validation studies establish modelling best-practice guidelines and the level of discrepancy against the analytical solutions or experimental measurements. Having developed the model and established its predictive capability, it is used to probe the hydrodynamics of weakly cohesive particles. Cohesive interactions are captured by employing a pair-wise van derWaals force model. The cohesive strength of the granular bed is quantified by the ratio of the maximum van der Waals force to the particle gravitational force, defined as the granular Bond number. The Bond number of the bed is increased…
Subjects/Keywords: 539.7; fluidization; DEM-CFD framework
…predictions and uniform bed expansion are captured in the DEM-CFD
framework. The expanded bed was… …Furthermore,
predictions of Umb by DEM-CFD simulations for weakly cohesive beds were compared… …2.6.4.2 DEM-CFD studies… …24
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4 Verification of the DEM-CFD model
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Gupta, P. (2015). Verification and validation of a DEM-CFD model and multiscale modelling of cohesive fluidization regimes. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/10449
Chicago Manual of Style (16th Edition):
Gupta, Prashant. “Verification and validation of a DEM-CFD model and multiscale modelling of cohesive fluidization regimes.” 2015. Doctoral Dissertation, University of Edinburgh. Accessed April 11, 2021.
http://hdl.handle.net/1842/10449.
MLA Handbook (7th Edition):
Gupta, Prashant. “Verification and validation of a DEM-CFD model and multiscale modelling of cohesive fluidization regimes.” 2015. Web. 11 Apr 2021.
Vancouver:
Gupta P. Verification and validation of a DEM-CFD model and multiscale modelling of cohesive fluidization regimes. [Internet] [Doctoral dissertation]. University of Edinburgh; 2015. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/1842/10449.
Council of Science Editors:
Gupta P. Verification and validation of a DEM-CFD model and multiscale modelling of cohesive fluidization regimes. [Doctoral Dissertation]. University of Edinburgh; 2015. Available from: http://hdl.handle.net/1842/10449

Louisiana State University
23.
Guedes de Oliveira, Daniel.
A Study of Particle-laden Flows from Meso and Micro-scale Perspectives.
Degree: PhD, Chemical Engineering, 2020, Louisiana State University
URL: https://digitalcommons.lsu.edu/gradschool_dissertations/5130
► Particle-laden flows are investigated numerically from a meso-scale perspective using Computational Fluid Dynamics coupled with Discrete Element Method (CFD-DEM) and from a micro-scale perspective…
(more)
▼ Particle-laden flows are investigated numerically from a meso-scale perspective using Computational Fluid Dynamics coupled with Discrete Element Method (CFD-DEM) and from a micro-scale perspective using Particle Resolved Direct Numerical Simulation (PR-DNS). For the former, the dynamics of a pseudo-2D pulsed fluidized bed (PFB) consisting of 400,000 to 800,000 particles was investigated (Chapters 2 and 3). The focus is on the capabilities of CFD-DEM to (1) reproduce pattern formation in these systems and (2) further the understanding of the dynamics of PFB's as a function of pulsation parameters. In Chapter 4, a two-spheres system is investigated with a recently implemented PR-DNS code, using the Basilisk open source framework. A high-resolution study is performed to investigate the flow field structures and their relation to experienced hydrodynamic forces by the spheres under the influence of a wall. In Appendix A, some verification and validation cases are reported with both the aforementioned codes, presenting capabilities that can be further explored in future work.
Subjects/Keywords: Particle-laden flows; bubble pattern; CFD-DEM; Pulsed-fluidized bed; DNS; Aligned-spheres
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Guedes de Oliveira, D. (2020). A Study of Particle-laden Flows from Meso and Micro-scale Perspectives. (Doctoral Dissertation). Louisiana State University. Retrieved from https://digitalcommons.lsu.edu/gradschool_dissertations/5130
Chicago Manual of Style (16th Edition):
Guedes de Oliveira, Daniel. “A Study of Particle-laden Flows from Meso and Micro-scale Perspectives.” 2020. Doctoral Dissertation, Louisiana State University. Accessed April 11, 2021.
https://digitalcommons.lsu.edu/gradschool_dissertations/5130.
MLA Handbook (7th Edition):
Guedes de Oliveira, Daniel. “A Study of Particle-laden Flows from Meso and Micro-scale Perspectives.” 2020. Web. 11 Apr 2021.
Vancouver:
Guedes de Oliveira D. A Study of Particle-laden Flows from Meso and Micro-scale Perspectives. [Internet] [Doctoral dissertation]. Louisiana State University; 2020. [cited 2021 Apr 11].
Available from: https://digitalcommons.lsu.edu/gradschool_dissertations/5130.
Council of Science Editors:
Guedes de Oliveira D. A Study of Particle-laden Flows from Meso and Micro-scale Perspectives. [Doctoral Dissertation]. Louisiana State University; 2020. Available from: https://digitalcommons.lsu.edu/gradschool_dissertations/5130

Virginia Tech
24.
Paul, Steven Timothy.
A Computational Framework for Fluid-Thermal Coupling of Particle Deposits.
Degree: MS, Mechanical Engineering, 2018, Virginia Tech
URL: http://hdl.handle.net/10919/83544
► This thesis presents a computational framework that models the coupled behavior between sand deposits and their surrounding fluid. Particle deposits that form in gas turbine…
(more)
▼ This thesis presents a computational framework that models the coupled behavior between sand deposits and their surrounding fluid. Particle deposits that form in gas turbine engines and industrial burners, can change flow dynamics and heat transfer, leading to performance degradation and impacting durability. The proposed coupled framework allows insight into the coupled behavior of sand deposits at high temperatures with the flow, which has not been available previously. The coupling is done by using a
CFD-
DEM framework in which a physics based collision model is used to predict the post-collision state-of-the-sand-particle. The collision model is sensitive to temperature dependent material properties of sand. Particle deposition is determined by the particle's softening temperature and the calculated coefficient of restitution of the collision. The multiphase treatment facilitates conduction through the porous deposit and the coupling between the deposit and the fluid field.
The coupled framework was first used to model the behavior of softened sand particles in a laminar impinging jet flow field. The temperature of the jet and the impact surface were varied(T^* = 1000 – 1600 K), to observe particle behavior under different temperature conditions. The Reynolds number(Rejet = 20, 75, 100) and particle Stokes numbers (Stp = 0.53, 0.85, 2.66, 3.19) were also varied to observe any effects the particles' responsiveness had on deposition and the flow field. The coupled framework was found to increase or decrease capture efficiency, when compared to an uncoupled simulation, by as much as 10% depending on the temperature field. Deposits that formed on the impact surface, using the coupled framework, altered the velocity field by as much as 130% but had a limited effect on the temperature field.
Simulations were also done that looked at the formation of an equilibrium deposit when a cold jet impinged on a relatively hotter surface, under continuous particle injection. An equilibrium deposit was found to form as deposited particles created a heat barrier on the high temperature surface, limiting more particle deposition. However, due to the transient nature of the system, the deposit temperature increased once deposition was halted. Further particle injection was not performed, but it can be predicted that the formed deposit would begin to grow again.
Additionally, a Large-Eddy Simulation (LES) simulation, with the inclusion of the Smagorinsky subgrid model, was performed to observe particle deposition in a turbulent flow field. Deposition of sand particles was observed as a turbulent jet (Re jet=23000,T_jet^*= 1200 K) impinged on a hotter surface(T_surf^*= 1600 K). Differences between the simulated flow field and relevant experiments were attributed to differing jet exit conditions and impact surface thermal conditions. The deposit was not substantive enough to have a significant effect on the flow field. With no difference in the flow field, no difference was found in the capture efficiency between the coupled and…
Advisors/Committee Members: Tafti, Danesh K. (committeechair), Dancey, Clinton L. (committee member), Ng, Wing Fai (committee member).
Subjects/Keywords: Computational Fluid Dynamics(CFD); Large-Eddy Simulation(LES); Discrete Element Method(DEM; Particle Deposition
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Paul, S. T. (2018). A Computational Framework for Fluid-Thermal Coupling of Particle Deposits. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/83544
Chicago Manual of Style (16th Edition):
Paul, Steven Timothy. “A Computational Framework for Fluid-Thermal Coupling of Particle Deposits.” 2018. Masters Thesis, Virginia Tech. Accessed April 11, 2021.
http://hdl.handle.net/10919/83544.
MLA Handbook (7th Edition):
Paul, Steven Timothy. “A Computational Framework for Fluid-Thermal Coupling of Particle Deposits.” 2018. Web. 11 Apr 2021.
Vancouver:
Paul ST. A Computational Framework for Fluid-Thermal Coupling of Particle Deposits. [Internet] [Masters thesis]. Virginia Tech; 2018. [cited 2021 Apr 11].
Available from: http://hdl.handle.net/10919/83544.
Council of Science Editors:
Paul ST. A Computational Framework for Fluid-Thermal Coupling of Particle Deposits. [Masters Thesis]. Virginia Tech; 2018. Available from: http://hdl.handle.net/10919/83544

University of Oxford
25.
Zhao, Tao.
Investigation of landslide-induced debris flows by the DEM and CFD.
Degree: PhD, 2014, University of Oxford
URL: http://ora.ox.ac.uk/objects/uuid:316cb3fc-dfc6-4e5a-bc0d-298e298c9c5b
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627853
► In recent years, the increasing impacts of landslide hazards on human lives and lifeline facilities worldwide has advanced the necessity to find out both economically…
(more)
▼ In recent years, the increasing impacts of landslide hazards on human lives and lifeline facilities worldwide has advanced the necessity to find out both economically acceptable and useful techniques to predict the occurrence and destructive power of landslides. Though many projects exist to attain this goal, the current investigation set out to establish an understanding of the initiation and propagation mechanisms of landslides via numerical simulations, so that mitigation strategies to reduce the long-term losses from landslide hazards can be made. In this research, the Discrete Element Method (DEM) and Computational Fluid Dynamics (CFD) have been used to investigate the mechanical and hydraulic behaviour of granular materials involved in landslides. The main challenge is to provide rational analyses of large scale landslides via small scale numerical simulations. To solve this problem, dimensional analyses have been performed on a simple granular column collapse model. The influence of governing dimensionless groups on the debris runout distance and deposit height has been studied for the terrestrial and submerged granular flows. 3D DEM investigations of granular flows in plane strain conditions have been performed in this research. The input parameters of the DEM model have been calibrated by the numerical triaxial tests, based on which, the relationships between the microscopic variables and the macroscopic soil strength properties are analysed. Using the simple granular column collapse model, the influences of column aspect ratio, characteristic strain, model size ratio and material internal friction angle on the runout distance and deposit height of granular materials have been examined. Additionally, the deformation and energy evolution of dry granular materials are also discussed. The DEM-CFD coupling model has been employed to study the mechanical and hydraulic behaviour of highly mobilized terrestrial / submarine landslides. This model has been validated via numerical simulations of fluid flow through a porous soil sample and grain batch sedimentations. The simulations of granular flows in the submerged environment have led to some meaningful insights into the flow mechanisms, such as the mobilization of sediments, the generation and dissipation of excess pore water pressures and the evolution of effective stresses. Overall, this study shows that the proposed numerical tools are capable of modelling the mechanical and hydraulic behaviour of terrestrial and submarine landslides.
Subjects/Keywords: 624.1; Geotechnical engineering; Civil engineering; landslide hazards; Discrete Element Method (DEM); Computational Fluid Dynamics (CFD); dimensional analyses; granular column collapse model; 3D DEM plane strain condition; DEM-CFD coupling; terrestrial / submarine landslides
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zhao, T. (2014). Investigation of landslide-induced debris flows by the DEM and CFD. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:316cb3fc-dfc6-4e5a-bc0d-298e298c9c5b ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627853
Chicago Manual of Style (16th Edition):
Zhao, Tao. “Investigation of landslide-induced debris flows by the DEM and CFD.” 2014. Doctoral Dissertation, University of Oxford. Accessed April 11, 2021.
http://ora.ox.ac.uk/objects/uuid:316cb3fc-dfc6-4e5a-bc0d-298e298c9c5b ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627853.
MLA Handbook (7th Edition):
Zhao, Tao. “Investigation of landslide-induced debris flows by the DEM and CFD.” 2014. Web. 11 Apr 2021.
Vancouver:
Zhao T. Investigation of landslide-induced debris flows by the DEM and CFD. [Internet] [Doctoral dissertation]. University of Oxford; 2014. [cited 2021 Apr 11].
Available from: http://ora.ox.ac.uk/objects/uuid:316cb3fc-dfc6-4e5a-bc0d-298e298c9c5b ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627853.
Council of Science Editors:
Zhao T. Investigation of landslide-induced debris flows by the DEM and CFD. [Doctoral Dissertation]. University of Oxford; 2014. Available from: http://ora.ox.ac.uk/objects/uuid:316cb3fc-dfc6-4e5a-bc0d-298e298c9c5b ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627853
26.
Jovanović Aca.
SIMULACIJA PROCESA KRETANJA ČESTICA PRI TRANSPORTU U STATIČKIM MEŠALICAMA I MODIFIKOVANIM PUŽNIM TRANSPORTERIMA PRIMENOM METODE DISKRETNIH ELEMENATA.
Degree: 2015, University of Novi Sad
URL: https://www.cris.uns.ac.rs/DownloadFileServlet/Disertacija144360160890056.pdf?controlNumber=(BISIS)95448&fileName=144360160890056.pdf&id=4377&source=OATD&language=en
;
https://www.cris.uns.ac.rs/record.jsf?recordId=95448&source=OATD&language=en
► Kvalitetno mešanje praškastih materijala, čestica ili granula je od izuzetnog inženjerskog, energetskog, ekonomskog i ekološkog značaja u raznim granama industrije: prehrambenoj, procesnoj, hemijskoj, farmaceutskoj…
(more)
▼ Kvalitetno mešanje praškastih materijala, čestica ili granula je od izuzetnog inženjerskog, energetskog, ekonomskog i ekološkog značaja u raznim granama industrije: prehrambenoj, procesnoj, hemijskoj, farmaceutskoj industriji. Efikasnost mešanja, dizajn opreme i parametri procesa mešanja imaju značajan uticaj na kvalitet i cenu poluproizvoda ili finalnog proizvoda. U ovoj tezi, prikazana je upotreba metode diskretnih elemenata (DEM) na modelovanje mešanja granula i/ili praškastih materijala (granulisani zeolit ili kukuruzna prekrupa) u različitim konfiguracijama statičkih mešača Komax i Ross, kao i za modifikovane pužne transportere / predmešalice. Primenjen je i metod računske dinamike fluida (CFD) za modelovanje protoka fluida u Ojlerovom višefaznom modelu, za predviđanje ponašanja čestica unutar različitih konfiguracija statičkih mešalica. Ispitivano je petnaest horizontalnih pužnih transportera sa nepromenljivog koraka, sa modifikovanom geometrijom, različitih dužina pužnice, sa dodatnim elementima na pužnoj spirali, radi istraživanja mogućnosti mešanja granulisanog materijala, tokom transporta materijala (granulisani zeolit). Rezultati matematičkog modeliranja i numeričke simulacije su upoređeni sa odgovarajućim eksperimentalnim rezultatima na osnovu stepena pomešanosti mešavine, primenom kriterijuma relativne standardne devijacije (RSD). Zahvaljujući ovde postavljenim modelima moguće je uraditi optimizaciju geometrije i parametara sistema mešanja uzimajući u obzir kvalitet procesa mešanja i cenu finalnog proizvoda.
The quality mixing of powders, particles and/or granules obtain an engineering, energetic, economic and ecological importance of various technologies, food industry, pharmaceutical and chemical industry. The mixing efficiency, the design of equipment and mixing parameters exert a strong impact on quality and the price of intermediate or final product. In this thesis, the use of Discrete Element Method (DEM) is shown for modeling of granular and/or powder flow in various multiple Komax and Ross mixing applications, as well as for the modified screw conveyors premixers . Computational Fluid Dynamic (CFD) method was used for modeling of fluid flow through Eulerian multiphase model, for the prediction of particle displacement within the various static mixers configurations. Fifteen horizontal screw conveyors with invariant pitch, with modified geometry and different screw length , with some additional elements welded on the helix were tested for the possibility of granular material mixing during the material transport (granulated zeolite). The results of the numerical simulation are compared with appropriate experimental results, according to relative standard deviation criterion (RSD). Application of this model provide the optimization of the geometry and parameters of mixing systems taking into account the quality of the mixing process and the cost of…
Advisors/Committee Members: Lević Ljubinko, Bera Oskar, Pavkov Ivan, Pezo Milada.
Subjects/Keywords: Statička mešalica, Pužni transporteri, CFD, DEM analiza, putanja čestica, optimizacija, vreme mešanja; Static mixer, Screw conveyors, DEM analysis, the trajectory of the particles, optimization, mixing time
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Aca, J. (2015). SIMULACIJA PROCESA KRETANJA ČESTICA PRI TRANSPORTU U STATIČKIM MEŠALICAMA I MODIFIKOVANIM PUŽNIM TRANSPORTERIMA PRIMENOM METODE DISKRETNIH ELEMENATA. (Thesis). University of Novi Sad. Retrieved from https://www.cris.uns.ac.rs/DownloadFileServlet/Disertacija144360160890056.pdf?controlNumber=(BISIS)95448&fileName=144360160890056.pdf&id=4377&source=OATD&language=en ; https://www.cris.uns.ac.rs/record.jsf?recordId=95448&source=OATD&language=en
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Aca, Jovanović. “SIMULACIJA PROCESA KRETANJA ČESTICA PRI TRANSPORTU U STATIČKIM MEŠALICAMA I MODIFIKOVANIM PUŽNIM TRANSPORTERIMA PRIMENOM METODE DISKRETNIH ELEMENATA.” 2015. Thesis, University of Novi Sad. Accessed April 11, 2021.
https://www.cris.uns.ac.rs/DownloadFileServlet/Disertacija144360160890056.pdf?controlNumber=(BISIS)95448&fileName=144360160890056.pdf&id=4377&source=OATD&language=en ; https://www.cris.uns.ac.rs/record.jsf?recordId=95448&source=OATD&language=en.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Aca, Jovanović. “SIMULACIJA PROCESA KRETANJA ČESTICA PRI TRANSPORTU U STATIČKIM MEŠALICAMA I MODIFIKOVANIM PUŽNIM TRANSPORTERIMA PRIMENOM METODE DISKRETNIH ELEMENATA.” 2015. Web. 11 Apr 2021.
Vancouver:
Aca J. SIMULACIJA PROCESA KRETANJA ČESTICA PRI TRANSPORTU U STATIČKIM MEŠALICAMA I MODIFIKOVANIM PUŽNIM TRANSPORTERIMA PRIMENOM METODE DISKRETNIH ELEMENATA. [Internet] [Thesis]. University of Novi Sad; 2015. [cited 2021 Apr 11].
Available from: https://www.cris.uns.ac.rs/DownloadFileServlet/Disertacija144360160890056.pdf?controlNumber=(BISIS)95448&fileName=144360160890056.pdf&id=4377&source=OATD&language=en ; https://www.cris.uns.ac.rs/record.jsf?recordId=95448&source=OATD&language=en.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Aca J. SIMULACIJA PROCESA KRETANJA ČESTICA PRI TRANSPORTU U STATIČKIM MEŠALICAMA I MODIFIKOVANIM PUŽNIM TRANSPORTERIMA PRIMENOM METODE DISKRETNIH ELEMENATA. [Thesis]. University of Novi Sad; 2015. Available from: https://www.cris.uns.ac.rs/DownloadFileServlet/Disertacija144360160890056.pdf?controlNumber=(BISIS)95448&fileName=144360160890056.pdf&id=4377&source=OATD&language=en ; https://www.cris.uns.ac.rs/record.jsf?recordId=95448&source=OATD&language=en
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Oulu
27.
Kulju, T. (Timo).
Utilization of phenomena-based modeling in unit operation design.
Degree: 2014, University of Oulu
URL: http://urn.fi/urn:isbn:9789526207124
► Abstract In the design and development of unit operations in chemical engineering, experimental testing is often very expensive or even impossible to perform. In these…
(more)
▼ Abstract
In the design and development of unit operations in chemical engineering, experimental testing is often very expensive or even impossible to perform. In these kinds of situations, numerical simulations offer a good approach to study process characteristics. Typically in chemical engineering, data-based modeling is applied to study the process. This requires many experiments for tuning the model parameters and validating the model. In a phenomenology-based approach, the evolution of the system is dictated by fluid and particle transport equations. These equations are independent of the process, and can therefore be applied in various systems. However, depending on the system, there are several aspects that have to be taken into account in order to choose the correct model for the problem in hand.
In this work, computational fluid dynamics (CFD) and discrete element method (DEM) modeling have been applied in different unit operations in the field of chemical engineering. CFD was applied in preventing sedimentation in a tube heat exchanger, estimating the cooling efficiency of a vertical water jet onto a hot metal plate, and studying the formation of the slag free open-eye area on the steel ladle. For comparison, DEM was applied in the continuous high-shear granulation of pharmaceutical powder. The different models used in this work are reviewed, and the results are presented from the point of view of model and process development. The grid aspects in CFD simulations and the termination criteria for DEM and CFD simulations are also studied.
Based on the results of this work, phenomenological modeling can be considered to be an efficient tool for unit operation design. Together with experimental work, different modeling strategies offer a powerful tool for the design and development of unit operations.
Tiivistelmä
Kemiantekniikan yksikköprosessien suunnittelussa kokeellinen tutkimus on usein erittäin kallista ja joskus jopa mahdotonta toteuttaa. Tällöin mallinnus tarjoaa hyvän lähestymistavan yksikköprosessin ominaisuuksien tutkimiselle. Tyypillisesti kemianteollisuudessa, datapohjaista mallinnusmenetelmiä on käytetty systeemin ominaisuuksien tutkimiseksi. Tämä menetelmä vaatii kuitenkin paljon koetoistoja mallin parametrien virittämiseksi ja mallin validoimiseksi. Ilmiöpohjaisessa mallinnuksessa, systeemin aikakehitys määräytyy fluidi- ja partikkelivirtauksia määräävien kuljetusyhtälöiden perusteella. Nämä yhtälöt ovat prosessista riippumattomia, jolloin niitä voidaan soveltaa yleisesti mihin tahansa systeemiin. Riippuen kuitenkin tutkittavasta yksikköprosessista, eri asioita on otettava huomioon, jotta oikea malli voidaan valita kuvaamaan systeemiä.
Tässä työssä virtauslaskentaa (computational fluid dynamics, CFD) ja partikkelimenetelmää (discrete element method, DEM) on käytetty erilaisten kemiantekniikan yksikköprosessien tutkimuksessa. CFD:n avulla on tutkittu putkilämmönvaihtimen sedimentaation ehkäisyä, laminaarisen suorasuihkujäähdytyksen tehokkuutta teräslevyn jäähdytyksessä, sekä…
Advisors/Committee Members: Muurinen, E. (Esa), Keiski, R. (Riitta).
Subjects/Keywords: chemical engineering; numerical modeling; phenomena-based modeling; unit process design; ilmiöpohjainen mallinnus; kemiantekniikka; numeerinen mallinnus; yksikköprosessien suunnittelu; CFD; DEM
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kulju, T. (. (2014). Utilization of phenomena-based modeling in unit operation design. (Doctoral Dissertation). University of Oulu. Retrieved from http://urn.fi/urn:isbn:9789526207124
Chicago Manual of Style (16th Edition):
Kulju, T (Timo). “Utilization of phenomena-based modeling in unit operation design.” 2014. Doctoral Dissertation, University of Oulu. Accessed April 11, 2021.
http://urn.fi/urn:isbn:9789526207124.
MLA Handbook (7th Edition):
Kulju, T (Timo). “Utilization of phenomena-based modeling in unit operation design.” 2014. Web. 11 Apr 2021.
Vancouver:
Kulju T(. Utilization of phenomena-based modeling in unit operation design. [Internet] [Doctoral dissertation]. University of Oulu; 2014. [cited 2021 Apr 11].
Available from: http://urn.fi/urn:isbn:9789526207124.
Council of Science Editors:
Kulju T(. Utilization of phenomena-based modeling in unit operation design. [Doctoral Dissertation]. University of Oulu; 2014. Available from: http://urn.fi/urn:isbn:9789526207124

Carnegie Mellon University
28.
Desai, Prathamesh.
Tribosurface Interactions involving Particulate Media with DEM-calibrated Properties: Experiments and Modeling.
Degree: 2017, Carnegie Mellon University
URL: http://repository.cmu.edu/dissertations/1123
► While tribology involves the study of friction, wear, and lubrication of interacting surfaces, the tribosurfaces are the pair of surfaces in sliding contact with a…
(more)
▼ While tribology involves the study of friction, wear, and lubrication of interacting surfaces, the tribosurfaces are the pair of surfaces in sliding contact with a fluid (or particulate) media between them. The ubiquitous nature of tribology is evident from the usage of its principles in all aspects of life, such as the friction promoting behavior of shoes on slippery water-lubricated walkways and tires on roadways to the wear of fingernails during filing or engine walls during operations. These tribosurface interfaces, due to the small length scales, are difficult to model for contact mechanics, fluid mechanics and particle dynamics, be it via theory, experiments or computations. Also, there is no simple constitutive law for a tribosurface with a particulate media. Thus, when trying to model such a tribosurface, there is a need to calibrate the particulate media against one or more property characterizing experiments. Such a calibrated media, which is the “virtual avatar” of the real particulate media, can then be used to provide predictions about its behavior in engineering applications. This thesis proposes and attempts to validate an approach that leverages experiments and modeling, which comprises of physics-based modeling and machine learning enabled surrogate modeling, to study particulate media in two key particle matrix industries: metal powder-bed additive manufacturing (in Part II), and energy resource rock drilling (in Part III). The physics-based modeling framework developed in this thesis is called the Particle-Surface Tribology Analysis Code (P-STAC) and has the physics of particle dynamics, fluid mechanics and particle-fluid-structure interaction. The Computational Particle Dynamics (CPD) is solved by using the industry standard Discrete Element Method (DEM) and the Computational Fluid Dynamics (CFD) is solved by using finite difference discretization scheme based on Chorin's projection method and staggered grids. Particle-structure interactions are accounted for by using a state-of-the art Particle Tessellated Surface Interaction Scheme and the fluid-structure interaction is accounted for by using the Immersed Boundary Method (IBM). Surrogate modeling is carried out using back propagation neural network. The tribosurface interactions encountered during the spreading step of the powder-bed additive manufacturing (AM) process which involve a sliding spreader (rolling and sliding for a roller) and particulate media consisting of metal AM powder, have been studied in Part II. To understand the constitutive behavior of metal AM powders, detailed rheometry experiments have been conducted in Chapter 5. CPD module of P-STAC is used to simulate the rheometry of an industry grade AM powder (100-250microns Ti-6Al-4V), to determine a calibrated virtual avatar of the real AM powder (Chapter 6). This monodispersed virtual avatar is used to perform virtual spreading on smooth and rough substrates in Chapter 7. The effect of polydispersity in DEM modeling is studied in Chapter 8. A polydispersed virtual avatar of…
Subjects/Keywords: Additive Manufacturing (AM); Computational Fluid Dynamics (CFD); Discrete Element Method (DEM); GPU Computing; Machine Learning; Rock Drilling
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Desai, P. (2017). Tribosurface Interactions involving Particulate Media with DEM-calibrated Properties: Experiments and Modeling. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/1123
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Desai, Prathamesh. “Tribosurface Interactions involving Particulate Media with DEM-calibrated Properties: Experiments and Modeling.” 2017. Thesis, Carnegie Mellon University. Accessed April 11, 2021.
http://repository.cmu.edu/dissertations/1123.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Desai, Prathamesh. “Tribosurface Interactions involving Particulate Media with DEM-calibrated Properties: Experiments and Modeling.” 2017. Web. 11 Apr 2021.
Vancouver:
Desai P. Tribosurface Interactions involving Particulate Media with DEM-calibrated Properties: Experiments and Modeling. [Internet] [Thesis]. Carnegie Mellon University; 2017. [cited 2021 Apr 11].
Available from: http://repository.cmu.edu/dissertations/1123.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Desai P. Tribosurface Interactions involving Particulate Media with DEM-calibrated Properties: Experiments and Modeling. [Thesis]. Carnegie Mellon University; 2017. Available from: http://repository.cmu.edu/dissertations/1123
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Université du Luxembourg
29.
Pozzetti, Gabriele.
A Dual-Grid Multiscale Approach to CFD-DEM Couplings for Multiphase Flow.
Degree: 2018, Université du Luxembourg
URL: http://orbilu.uni.lu/handle/10993/36897
► This thesis focuses on a novel dual-grid multiscale approach to CFD- DEM1 couplings, proposes its advantages in terms of numerical proper- ties and performance, and…
(more)
▼ This thesis focuses on a novel dual-grid multiscale approach to
CFD-
DEM1 couplings, proposes its advantages in terms of numerical proper-
ties and performance, and provides examples of engineering applications
that can benefit from it. In recent years,
CFD-
DEM couplings are be-
coming a more and more adopted solution for the numerical simulation
of particle-laden flows. In particular, couplings based on the volume av-
eraging technique have become a standard for numerical simulations in
chemical and process engineering. Furthermore, they are rapidly spread-
ing to civil, geotechnical and mechanical applications due to their ability
in dealing with arbitrarily complex mixtures of continuum and granular
media.
Despite the several advantages that these Eulerian-Lagrangian cou-
plings provide, their rigorous application to complex scenarios is currently
limited by two main factors. First, the computational traceability of the
solutions can become problematic due to the lack of a general theory on
the
subject. In particular, grid-convergence studies for the solution of the
continuous phases are often not feasible due to the averaging procedure
that imposes limitations on the grid structure and refinement. Second,
the parallel implementation of these numerical schemes holds important
disadvantages in terms of memory consumption and inter-physics com-
munication load. These disadvantages are significantly limiting the ex-
tension of these approaches to large-scale scenarios.
This thesis collects some of the most significant works published in
the last years on a novel approach that allows solving the two above-
mentioned problems, and, therefore, tackling more complex and expen-
sive scenarios. I refer to this approach as dual-grid multiscale approach
for
CFD-
DEM couplings. It consists in using two different computational
grids, one for the coupling between continuum and discrete entities and
one for the solution of the so-obtained continuum equations. The two
grids, i.e. the two problems, are in this way resolved on two different
scales. The first scale or “bulk” scale is chosen to optimize the averag-
ing operation. At this length-scale, the discrete entities are considered
as zero-dimensional, and interact with the fluid with local exchanges of
momentum, mass, and energy. The second scale or “fluid-fine” scale is
identified as the one at which a unique solution for the averaged equa-
tions can be provided. In practice, this is chosen as the one at which the
solution of the fluid equations becomes grid-independent. An inter-scale
communication is adopted by interpolating fields from the fluid-fine scale
to the bulk one and vice-versa.
The theoretical description of the method is first provided with par-
ticular reference to the
DEM-VOF coupling. Even in its simplest version,
the multiscale approach is shown to generate grid-convergent solutions
and significantly higher accuracy than a standard
CFD-
DEM coupling.
This shows how the new approach is able to overcome the first main
limitation described above.
Then, an…
Advisors/Committee Members: Peters, Bernhard [superviser], Zilian, Andreas [president of the jury], Bordas, Stéphane [member of the jury], Mahmouidi, Amir [member of the jury], Useldinger, Ralph [member of the jury], Varrette, Sébastien [member of the jury].
Subjects/Keywords: Multiscale; CFD-DEM; Engineering, computing & technology :: Multidisciplinary, general & others [C99]; Ingénierie, informatique & technologie :: Multidisciplinaire, généralités & autres [C99]
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Pozzetti, G. (2018). A Dual-Grid Multiscale Approach to CFD-DEM Couplings for Multiphase Flow. (Doctoral Dissertation). Université du Luxembourg. Retrieved from http://orbilu.uni.lu/handle/10993/36897
Chicago Manual of Style (16th Edition):
Pozzetti, Gabriele. “A Dual-Grid Multiscale Approach to CFD-DEM Couplings for Multiphase Flow.” 2018. Doctoral Dissertation, Université du Luxembourg. Accessed April 11, 2021.
http://orbilu.uni.lu/handle/10993/36897.
MLA Handbook (7th Edition):
Pozzetti, Gabriele. “A Dual-Grid Multiscale Approach to CFD-DEM Couplings for Multiphase Flow.” 2018. Web. 11 Apr 2021.
Vancouver:
Pozzetti G. A Dual-Grid Multiscale Approach to CFD-DEM Couplings for Multiphase Flow. [Internet] [Doctoral dissertation]. Université du Luxembourg; 2018. [cited 2021 Apr 11].
Available from: http://orbilu.uni.lu/handle/10993/36897.
Council of Science Editors:
Pozzetti G. A Dual-Grid Multiscale Approach to CFD-DEM Couplings for Multiphase Flow. [Doctoral Dissertation]. Université du Luxembourg; 2018. Available from: http://orbilu.uni.lu/handle/10993/36897

Université du Luxembourg
30.
Mohseni, Seyedmohammad.
DRYING AND CONVERSION ANALYSIS OF BIOMASS BY A DEM-CFD COUPLING APPROACH.
Degree: 2017, Université du Luxembourg
URL: http://orbilu.uni.lu/handle/10993/33153
► Biomass materials as a type of renewable energy sources have attracted many attention nowadays to decrease fossil fuel usage due to ecological and economical benefits.…
(more)
▼ Biomass materials as a type of renewable energy sources have attracted many attention nowadays to decrease fossil fuel usage due to ecological and economical benefits. The main objective of this PhD thesis is studying the drying and conversion of biomass materials with employing a hybrid four-way
DEM-
CFD coupling approach in which considers the solid particulates as discrete elements coupled via heat, mass and momentum transfer to the surrounding gas as continuous phase. Where a comprehensive three-dimensional numerical model is developed and applied to investigate the complex phenomena taking place during biomass drying and conversion in a reactor. That is referred to take into account the physical and chemical processes as heat-up, drying, pyrolysis, gasification and combustion including the essential heterogeneous and homogeneous reactions which is considered as an interactive solid-gas multiphase system. In the proposed model, the motion and thermodynamic state of the particles are involved with employing the relevant governing equations. Where the conductive and radiative heat transfer between particles as well as convective heat transfer between particles and gas phase are taken into account. In addition, some interfaces are extended for coupling the solid particles and the gas phase to consider the interactions in between. At first, the importance of biomass resources is discussed and then the mathematical modeling employed in the PhD thesis is explained thoroughly. To apply the model, four different cases are assessed where two chapters discuss the drying behavior of biomass particles in two different situations. Afterwards, the motion of solid particles in a bubbling fluidized bed is examined. Finally, the conversion of wood materials in a bubbling fluidized bed is determined.
Advisors/Committee Members: Peters, Bernhard [superviser], Greger, Manfred [president of the jury], Beckmann, Michael [member of the jury], Dziugys, Algis [member of the jury], Mahmoudi, Amirhoushang [member of the jury].
Subjects/Keywords: CFD-DEM; Biomass Conversion; OpenFOAM; Engineering, computing & technology :: Mechanical engineering [C10]; Ingénierie, informatique & technologie :: Ingénierie mécanique [C10]
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mohseni, S. (2017). DRYING AND CONVERSION ANALYSIS OF BIOMASS BY A DEM-CFD COUPLING APPROACH. (Doctoral Dissertation). Université du Luxembourg. Retrieved from http://orbilu.uni.lu/handle/10993/33153
Chicago Manual of Style (16th Edition):
Mohseni, Seyedmohammad. “DRYING AND CONVERSION ANALYSIS OF BIOMASS BY A DEM-CFD COUPLING APPROACH.” 2017. Doctoral Dissertation, Université du Luxembourg. Accessed April 11, 2021.
http://orbilu.uni.lu/handle/10993/33153.
MLA Handbook (7th Edition):
Mohseni, Seyedmohammad. “DRYING AND CONVERSION ANALYSIS OF BIOMASS BY A DEM-CFD COUPLING APPROACH.” 2017. Web. 11 Apr 2021.
Vancouver:
Mohseni S. DRYING AND CONVERSION ANALYSIS OF BIOMASS BY A DEM-CFD COUPLING APPROACH. [Internet] [Doctoral dissertation]. Université du Luxembourg; 2017. [cited 2021 Apr 11].
Available from: http://orbilu.uni.lu/handle/10993/33153.
Council of Science Editors:
Mohseni S. DRYING AND CONVERSION ANALYSIS OF BIOMASS BY A DEM-CFD COUPLING APPROACH. [Doctoral Dissertation]. Université du Luxembourg; 2017. Available from: http://orbilu.uni.lu/handle/10993/33153
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