subject:(drag force)

University of Alberta

1. Rabiei, Montazar. Pullback Force Evaluation of Pipes Installed via Horizontal Directional Drilling.

Degree: PhD, Department of Civil and Environmental Engineering, 2016, University of Alberta

URL: https://era.library.ualberta.ca/files/czg64tm18b

► Since its first application in the 1970s, Horizontal Directional Drilling (HDD) has steadily become one of the fastest growing trenchless construction methods for utility and… (more)

▼ Since its first application in the 1970s, Horizontal Directional Drilling (HDD) has steadily become one of the fastest growing trenchless construction methods for utility and conduit installation under surface obstacles. This rapid growth in HDD application could not have been accomplished without major development in engineering and design procedures, which take into account the unique characteristics of this technology. As a result, the most current HDD design references, at least to some extent, rely on studies carried out in other industries, e.g., oil well drilling and utility cable installation. These adoptions are often made without making proper adjustments, leading to inaccurate pipe designs. This dissertation aims to identify and address the shortcomings that exist in current pullback determination methods during pipe installation by HDD. Throughout the study, special attention is paid to the investigation and refinement of the proposed procedures by the two reference design documents used widely in North America: the ASTM F1962 method and the Pipeline Research Council International (PRCI) method, used for HDPE and steel pipe design, respectively. The dissertation is heavily tilted toward investigating the pipe-drilling fluid interaction since several studies have emphasized the necessity of refining the current practice of fluidic drag calculation. Two new methods for calculating fluidic drag are introduced: one applicable to power-law fluids and the other one for Herschel-Bulkley fluids. The latter accounts for pipe eccentricity and is based on the application of Finite Volume Method (FVM) to the HDD drilling fluid flow problem. Also, a series of simple methods for fluidic drag estimation are proposed, which are suitable for HDD practitioners to use and can be incorporated into future standards. For estimating the non-fluidic drag component of pullback force, two different models have been developed: one for steel pipes and the other for HDPE pipes. Unlike the PRCI method, the former doesn’t involve an iterative procedure and, contrary to the ASTM F1962 method, the latter is not limited to crossings with specific bore geometry. For verification of the developed methods and models, pullback data collected on different crossings has been used. The data is provided by The Crossing Company (TCC), the industry partner of the Consortium for Engineered Trenchless Technologies (CETT) at the University of Alberta, and collected on different project sites for crossings executed in Alberta, Canada. The new proposed models have been able to simulate the recorded pullback forces, while the PRCI method failed to do so. It has been observed that the fluidic drag changes almost linearly with the installation progress; therefore, simple methods based on adaption of the pipe annulus to a slot can be used for estimating the fluidic drag. Furthermore, the fluidic drag is not a direct function of hydrokinetic pressure and, as a result, methods like ASTM F 1962 fail to predict the fluidic drag changes accurately. The FVM…

Subjects/Keywords: Horizontal Directional Drilling; Pullback Force; Fluidic Drag; Frictional Drag; Finite Volume Method; PRCI; ASTM F1962

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rabiei, M. (2016). Pullback Force Evaluation of Pipes Installed via Horizontal Directional Drilling. (Doctoral Dissertation). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/czg64tm18b

Chicago Manual of Style (16^th Edition):

Rabiei, Montazar. “Pullback Force Evaluation of Pipes Installed via Horizontal Directional Drilling.” 2016. Doctoral Dissertation, University of Alberta. Accessed January 24, 2021. https://era.library.ualberta.ca/files/czg64tm18b.

MLA Handbook (7^th Edition):

Rabiei, Montazar. “Pullback Force Evaluation of Pipes Installed via Horizontal Directional Drilling.” 2016. Web. 24 Jan 2021.

Vancouver:

Rabiei M. Pullback Force Evaluation of Pipes Installed via Horizontal Directional Drilling. [Internet] [Doctoral dissertation]. University of Alberta; 2016. [cited 2021 Jan 24]. Available from: https://era.library.ualberta.ca/files/czg64tm18b.

Council of Science Editors:

Rabiei M. Pullback Force Evaluation of Pipes Installed via Horizontal Directional Drilling. [Doctoral Dissertation]. University of Alberta; 2016. Available from: https://era.library.ualberta.ca/files/czg64tm18b

University of Akron

2. Fang, Jia. Study of Liquid Drop Migration on Fibers and Mats due to Liquid Flow in a Thin Slit Geometry.

Degree: PhD, Chemical Engineering, 2015, University of Akron

URL: http://rave.ohiolink.edu/etdc/view?acc_num=akron1446730097

► ABSTRACTThe movement of liquid drops on fibers and mats commonly occurs in fabrics used in household and commercial applications. Removal of the liquid droplets from… (more)

▼ ABSTRACTThe movement of liquid drops on fibers and mats commonly occurs in fabrics used in household and commercial applications. Removal of the liquid droplets from the gas/liquid and liquid/liquid streams will be of benefit for the health of the workers, safety of the environment, and protection of equipment. For example, the presence of water in diesel fuel may lead to some problems such as plugging of fuel injectors, reduce fuel flow rate, reduce fuel lubricity, and cause corrosion of engine parts. It is better to design a self-cleaning filter, which could be used to collect the liquid droplets and drain to a collecting device. This filter has advantages of reducing the cleaning cost and extending the filter life. The quality factor is used to evaluate the performance of the filter, which is related to the separation efficiency and pressure drop. The separation efficiency is strongly related to the velocity of drops on the fibers and mats. The drag coefficient correlation is used to estimate the average velocity of drop moving on the fiber/mat surfaces. In this work, the drag coefficient is correlated to Reynolds and capillary numbers from experiments and models. The flow direction is parallel the fibers and mats. In the gas-liquid experiment, the experiments are conducted for different types of fibers and different liquids. In the liquid-liquid experiment, the experiments are conducted for water drop moving on different types of mat surfaces. Also, other correlations have been derived to estimate the minimum gas/liquid flow Reynolds numbers to initiate the drop movement on fiber and mat surfaces. Finally, when the flow direction is through the filter medium (perpendicular to the fiber mat surface), another correlation is derived to estimate the minimum flow rate to move the water droplets through the pores of the mats. These correlations are unique to determine the average velocities of the liquid drops on fiber/mat surfaces. The motion of drops on fibers and woven mats are not widely discussed in literature. Very few papers have been published on the development of such correlations to estimate the drop migration on fibers/mats which makes this work unique. Advisors/Committee Members: George, Chase (Advisor).

Subjects/Keywords: Chemical Engineering; filter media, coalescence, wettability, drag coefficient, drag force, drop motion

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APA (6^th Edition):

Fang, J. (2015). Study of Liquid Drop Migration on Fibers and Mats due to Liquid Flow in a Thin Slit Geometry. (Doctoral Dissertation). University of Akron. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=akron1446730097

Chicago Manual of Style (16^th Edition):

Fang, Jia. “Study of Liquid Drop Migration on Fibers and Mats due to Liquid Flow in a Thin Slit Geometry.” 2015. Doctoral Dissertation, University of Akron. Accessed January 24, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1446730097.

MLA Handbook (7^th Edition):

Fang, Jia. “Study of Liquid Drop Migration on Fibers and Mats due to Liquid Flow in a Thin Slit Geometry.” 2015. Web. 24 Jan 2021.

Vancouver:

Fang J. Study of Liquid Drop Migration on Fibers and Mats due to Liquid Flow in a Thin Slit Geometry. [Internet] [Doctoral dissertation]. University of Akron; 2015. [cited 2021 Jan 24]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=akron1446730097.

Council of Science Editors:

Fang J. Study of Liquid Drop Migration on Fibers and Mats due to Liquid Flow in a Thin Slit Geometry. [Doctoral Dissertation]. University of Akron; 2015. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=akron1446730097

Universidade do Rio Grande do Sul

3. Gomes, Lara Elena. Comparação entre forças propulsivas efetivas calculadas e medida durante um palmateio de sustentação.

Degree: 2010, Universidade do Rio Grande do Sul

URL: http://hdl.handle.net/10183/27677

►

A força propulsiva gerada durante o palmateio é resultado do somatório das forças de arrasto e de sustentação, sendo que a componente que atua na… (more)

▼

A força propulsiva gerada durante o palmateio é resultado do somatório das forças de arrasto e de sustentação, sendo que a componente que atua na direção do movimento desejado é igual à força propulsiva efetiva. Essas forças podem ser estimadas a partir de equações hidrodinâmicas, porém essas equações não consideram todos os mecanismos que contribuem para a propulsão. Dessa forma, o objetivo geral do presente estudo foi comparar a força propulsiva efetiva calculada a partir das equações hidrodinâmicas e a força propulsiva efetiva medida durante o palmateio de sustentação (na posição vertical, de cabeça para cima) em cada fase do palmateio. Para isso, uma praticante de nado sincronizado realizou palmateio na posição vertical de cabeça para cima durante 15 segundos, enquanto que dados cinemáticos e cinéticos foram obtidos por viodeogrametria 3D e dinamometria respectivamente. A análise gráfica de Bland e Altman foi usada para comparar as forças propulsivas efetivas medida e calculada durante o palmateio. As forças propulsivas efetivas calculada e medida foram diferentes, sendo a medida maior que a calculada. Ainda, os resultados indicaram que o palmateio executado não foi simétrico, isto é, a orientação e a força propulsiva entre a mão direita e a esquerda foram diferentes. Portanto, o achado do presente trabalho destaca a importância de mecanismos instáveis para a propulsão durante o palmateio, já que as forças estimadas por meio das equações hidrodinâmicas apresentaram resultados inferiores, sendo isso observado ao longo de todo o palmateio.

Propulsive force generated during sculling motion results from drag and lift propulsive forces, and the component acting in the direction of motion is the effective propulsive force. These forces may be calculated using hydrodynamic equations, but these equations do not consider all mechanisms that contribute to the propulsion. Thus, the main purpose of this study was to compare the calculated effective propulsive force using the hydrodynamic equations and the measured effective propulsive force during a support sculling motion (vertical position with the head above the water‟s surface) in each phase of sculling. For this, a practitioner of synchronized swimming performed sculling motion in a vertical position with the head above the water‟s surface during 15 seconds, while kinematic and kinetic data were obtained by 3D videogrammetry and dynamometry respectively. Graphical techniques from Bland and Altman were used to compare the measured effective propulsive force and calculated effective propulsive force during sculling motion. The calculated effective propulsive force and the measured effective propulsive force were different, the measured being greater than the calculated. Moreover, the results indicated sculling motion performed was not symmetric, that is, the orientation and propulsive forces between the right and left hands were different. Therefore, the result of this study highlights the importance of the unsteady mechanisms for the propulsion during sculling…

Advisors/Committee Members: Loss, Jefferson Fagundes.

Subjects/Keywords: Propulsion; Biomecânica; Attack angle; Natação : Fisiologia; Força; Drag force; Lift force; Swimming; Synchronized swimming

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APA (6^th Edition):

Gomes, L. E. (2010). Comparação entre forças propulsivas efetivas calculadas e medida durante um palmateio de sustentação. (Thesis). Universidade do Rio Grande do Sul. Retrieved from http://hdl.handle.net/10183/27677

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gomes, Lara Elena. “Comparação entre forças propulsivas efetivas calculadas e medida durante um palmateio de sustentação.” 2010. Thesis, Universidade do Rio Grande do Sul. Accessed January 24, 2021. http://hdl.handle.net/10183/27677.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gomes, Lara Elena. “Comparação entre forças propulsivas efetivas calculadas e medida durante um palmateio de sustentação.” 2010. Web. 24 Jan 2021.

Vancouver:

Gomes LE. Comparação entre forças propulsivas efetivas calculadas e medida durante um palmateio de sustentação. [Internet] [Thesis]. Universidade do Rio Grande do Sul; 2010. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/10183/27677.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gomes LE. Comparação entre forças propulsivas efetivas calculadas e medida durante um palmateio de sustentação. [Thesis]. Universidade do Rio Grande do Sul; 2010. Available from: http://hdl.handle.net/10183/27677

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

4. Buckman, L.J. (author). Hydrodynamics of partially vegetated channels: Stem drag forces and application to an in-stream wetland concept for tropical, urban drainage systems.

Degree: 2013, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:71f7e38d-a05b-4e6e-bb84-88fa4d6f31b9

► Introduction: The addition of vegetation to the banks urban drainage channels is an increasingly common measure for improving water quality, enhancing ecological health, and improving… (more)

▼ Introduction: The addition of vegetation to the banks urban drainage channels is an increasingly common measure for improving water quality, enhancing ecological health, and improving aesthetic appeal. An in-stream wetland concept is proposed for channels in Singapore to just that, but faces a major challenge in that high flow rates during storm events will increase the risk of damage to the vegetation. Problem definition: In high-flow situations, flow around the vegetation causes a region of turbulent shear to develop along the interface between the vegetation and main, open-channel flow. This is expected to impact the hydraulic resistance in the channel and the drag forces experience by individual plants, especially those nearest to the interface. For design it is important to understand the effects of this turbulent shear on drag to optimize design to limit upstream flooding risk and assess the risks of damage to plants. Research: The aim of the research was to increase understanding of the effects of lateral, turbulent shear on the channel resistance and forces experienced by individual stems in a uniform patch of vegetation. A patch of uniform vegetation was modelled by an array of rigid cylinders in an experimental flume. Measurements of the flow field and the drag forces on individual cylinders were recorded. Using this data, answers to the following questions were found: 1) What is the effect of lateral turbulent motion on channel resistance? 2) How do drag forces on individual stems vary spatially over the patch and in time, with special attention to local maximums? 3) What is the effect of lateral turbulent motion on fluctuations in the stem drag force? 4) What are the implications for estimation of the mean and maximum stem drag forces? Results: Analysis of the experimental results revealed the following: 1) The presence of a lateral shear layer significantly increased channel resistance, by 175% when compared to similar conditions when the shear layer was not allowed to develop. 2) Drag forces on stems mirrored the velocity distributions in both time and space, showing both higher mean and maximum values near the interface between the stem array and open channel. 3) Similar periodicity in the velocity and force signals gave evidence of coherent, turbulent structures as the primary means of momentum transport across the vegetation interface. This motion causes a sweep-ejection pattern in the flow at the interface with a net flux of momentum towards the vegetation, resulting in a skewed distribution of stem forces towards higher extreme values. Conclusions and recommendations: Lateral turbulent shear is an important factor in both the channel resistance and stem drag forces in a partially vegetated channel. Coherent structures at the vegetation interface were determined to be the main factor in stem force distribution within the region of shear. The mean stem force can be derived directly from the mean velocity given adequate assumptions of the vegetative drag coefficients. A conceptual model was developed… Advisors/Committee Members: Uijttewaal, W.S.J. (mentor).

Subjects/Keywords: vegetation; hydrodynamics; drag force

…12 Stem drag force within a vegetated field… …27 Stem drag force… …34 4.4.1 Average and maximum stem drag force… …40 4.5.3 Stem drag force… …force . . . . . . . . . . . . . . . . . . . . . . 47 5.2 Estimation of the stem drag forces…

10 more images…

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APA (6^th Edition):

Buckman, L. J. (. (2013). Hydrodynamics of partially vegetated channels: Stem drag forces and application to an in-stream wetland concept for tropical, urban drainage systems. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:71f7e38d-a05b-4e6e-bb84-88fa4d6f31b9

Chicago Manual of Style (16^th Edition):

Buckman, L J (author). “Hydrodynamics of partially vegetated channels: Stem drag forces and application to an in-stream wetland concept for tropical, urban drainage systems.” 2013. Masters Thesis, Delft University of Technology. Accessed January 24, 2021. http://resolver.tudelft.nl/uuid:71f7e38d-a05b-4e6e-bb84-88fa4d6f31b9.

MLA Handbook (7^th Edition):

Buckman, L J (author). “Hydrodynamics of partially vegetated channels: Stem drag forces and application to an in-stream wetland concept for tropical, urban drainage systems.” 2013. Web. 24 Jan 2021.

Vancouver:

Buckman LJ(. Hydrodynamics of partially vegetated channels: Stem drag forces and application to an in-stream wetland concept for tropical, urban drainage systems. [Internet] [Masters thesis]. Delft University of Technology; 2013. [cited 2021 Jan 24]. Available from: http://resolver.tudelft.nl/uuid:71f7e38d-a05b-4e6e-bb84-88fa4d6f31b9.

Council of Science Editors:

Buckman LJ(. Hydrodynamics of partially vegetated channels: Stem drag forces and application to an in-stream wetland concept for tropical, urban drainage systems. [Masters Thesis]. Delft University of Technology; 2013. Available from: http://resolver.tudelft.nl/uuid:71f7e38d-a05b-4e6e-bb84-88fa4d6f31b9

5. Mueller, Eric Victor. LES Modeling of Flow through Vegetation with Applications to Wildland Fires.

Degree: MS, 2012, Worcester Polytechnic Institute

URL: etd-042612-112043 ; https://digitalcommons.wpi.edu/etd-theses/334

► Due to continued outward expansion of industry and community development into the wildland-urban interface (WUI), the threat to life safety and property from wildland fires… (more)

▼ Due to continued outward expansion of industry and community development into the wildland-urban interface (WUI), the threat to life safety and property from wildland fires has become a significant problem. Such fire scenarios can be better understood through the use of computation fluid dynamics based fire-spread models. However, current physical fire models must be specifically adapted to handle the phenomena associated with WUI fires. Only then can they be reliably used as research and decision making tools to help mitigate the problem. In this research, the current standard in wildland fire modeling for representing the effect on wind flow from a porous vegetative medium is examined. The technique used employs basic correlations for object drag, and its validity with respect to real vegetation has yet to be examined in detail by the scientific community. The modeling of vegetation is studied within the framework of the existing Wildland-Urban Interface Fire Dynamics Simulator (WFDS), and the potential need for continued development is assessed. Comparisons are made to both experimental and numerical studies. Additionally, the validity of the model is considered at both the scale of an individual tree, as well as that of a whole forest canopy. Results show that as a first approximation the model is able to perform well in the latter case. At the scale of an individual tree, however, the behavior is governed by theoretical constants. The assumption of cylindrical vegetation elements performs slightly better than the commonly used spherical case, but neither adequately captures experimental tendencies. Accurate flow representation for single trees is crucial to modeling the key driving factors of fire behavior (such as combustion and heat transfer) in small scale WUI scenarios. Ultimately, this study illustrates the need for well-designed experiments, specifically to generate empirical constants which will improve the behavior of the simplified theory. Advisors/Committee Members: Albert Simeoni, Advisor, Ali S. Rangwala, Committee Member, Kathy A. Notarianni, Department Head, William Mell.

Subjects/Keywords: vegetation; wind; les; cfd; wildland fires; drag force

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APA (6^th Edition):

Mueller, E. V. (2012). LES Modeling of Flow through Vegetation with Applications to Wildland Fires. (Thesis). Worcester Polytechnic Institute. Retrieved from etd-042612-112043 ; https://digitalcommons.wpi.edu/etd-theses/334

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Mueller, Eric Victor. “LES Modeling of Flow through Vegetation with Applications to Wildland Fires.” 2012. Thesis, Worcester Polytechnic Institute. Accessed January 24, 2021. etd-042612-112043 ; https://digitalcommons.wpi.edu/etd-theses/334.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Mueller, Eric Victor. “LES Modeling of Flow through Vegetation with Applications to Wildland Fires.” 2012. Web. 24 Jan 2021.

Vancouver:

Mueller EV. LES Modeling of Flow through Vegetation with Applications to Wildland Fires. [Internet] [Thesis]. Worcester Polytechnic Institute; 2012. [cited 2021 Jan 24]. Available from: etd-042612-112043 ; https://digitalcommons.wpi.edu/etd-theses/334.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Mueller EV. LES Modeling of Flow through Vegetation with Applications to Wildland Fires. [Thesis]. Worcester Polytechnic Institute; 2012. Available from: etd-042612-112043 ; https://digitalcommons.wpi.edu/etd-theses/334

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Virginia Tech

6. Larson, Christopher Whitford. The Design and Construction of a 20" x 20" Mach 2.0 Blowdown Wind Tunnel to Characterize the Lift and Drag of Irregularly Shaped Fragments.

Degree: MS, Mechanical Engineering, 2011, Virginia Tech

URL: http://hdl.handle.net/10919/76968

► A supersonic wind tunnel, with a 20" x 20'" test section cross sectional area, was designed and constructed at the Techsburg Wind Tunnel Facility in… (more)

▼ A supersonic wind tunnel, with a 20" x 20'" test section cross sectional area, was designed and constructed at the Techsburg Wind Tunnel Facility in order to determine the lift and drag on irregularly shaped fragments in supersonic flow. Prior to beginning the wind tunnel design process, a blowdown analysis model was created in order to determine the influence of a number of parameters on tunnel run time and test gas properties throughout the tunnel circuit. The design of the settling chamber, test section, supersonic nozzles, diffuser, and exhaust are presented in this thesis. Diffuser performance has a large influence on wind tunnel efficiency and run time. Therefore, significant efforts should be taken in order to attain the highest possible pressure recovery within the diffuser. The design of wind tunnel components, as well as their stress analysis, was conducted using SolidWorks. The control valve and silencer were sized and selected for the expected tunnel operating conditions. Since the control valve tends to encompass a significant portion of the overall tunnel cost, care must be taken to ensure it has a large enough flow capacity to produce the desired test conditions. Also, attempts must be made to accurately predict the total pressure loss through the silencer, since this loss can have a large impact on the total pressure ratio necessary to produce the design Mach number. Upon completion of the design process, the supersonic wind tunnel was assembled, and shakedown testing was conducted. During shakedown testing it was determined that the wind tunnel was capable of producing Mach 2 flow in the test section. Following shakedown testing, a flow survey was conducted in order to ensure uniform Mach number flow exists throughout the region occupied by the fragments. Based on the flow survey it was determined that within the middle 60% of the test section, the average Mach number was 1.950 and varied by only 0.56% within this region. Two irregularly shaped fragments were tested at Mach 2 flow, over an effective 360° pitch sweep, with wind tunnel runs performed every 10 degrees. Based on the measured force data for both fragments, the lift appeared to follow a sinusoidal curve, with minimum values at 0, 90, and 180° balance pitch angle, and maximum values occurring around 45 and 135° pitch angle. The drag force was observed to follow a gradual curve with minimum values at 0 and 180° balance pitch angle, as expected since the fragment presented area is generally least in this orientation. The maximum drag was found to occur at a balance pitch angle of 90°, once again as expected since the fragment presented area is generally greatest at this angle. It was also observed that the fragment drag tended to be greater for a fragment orientation which places the concave side of the fragment into the direction of the flow. Advisors/Committee Members: Ng, Wing Fai (committeechair), Diller, Thomas E. (committee member), Dancey, Clinton L. (committeecochair).

Subjects/Keywords: Irregularly Shaped Fragments; Lift and Drag Force; Supersonic Wind Tunnel

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APA (6^th Edition):

Larson, C. W. (2011). The Design and Construction of a 20" x 20" Mach 2.0 Blowdown Wind Tunnel to Characterize the Lift and Drag of Irregularly Shaped Fragments. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/76968

Chicago Manual of Style (16^th Edition):

Larson, Christopher Whitford. “The Design and Construction of a 20" x 20" Mach 2.0 Blowdown Wind Tunnel to Characterize the Lift and Drag of Irregularly Shaped Fragments.” 2011. Masters Thesis, Virginia Tech. Accessed January 24, 2021. http://hdl.handle.net/10919/76968.

MLA Handbook (7^th Edition):

Larson, Christopher Whitford. “The Design and Construction of a 20" x 20" Mach 2.0 Blowdown Wind Tunnel to Characterize the Lift and Drag of Irregularly Shaped Fragments.” 2011. Web. 24 Jan 2021.

Vancouver:

Larson CW. The Design and Construction of a 20" x 20" Mach 2.0 Blowdown Wind Tunnel to Characterize the Lift and Drag of Irregularly Shaped Fragments. [Internet] [Masters thesis]. Virginia Tech; 2011. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/10919/76968.

Council of Science Editors:

Larson CW. The Design and Construction of a 20" x 20" Mach 2.0 Blowdown Wind Tunnel to Characterize the Lift and Drag of Irregularly Shaped Fragments. [Masters Thesis]. Virginia Tech; 2011. Available from: http://hdl.handle.net/10919/76968

7. Holopainen, Rauno. Dust in Ventilation Ducts: Accumulation, Measurement and Removal.

Degree: 2004, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2004/isbn9512269767/

►

This thesis focuses on dust accumulation in, and removal from, recently installed supply air ducts and on the bristle behaviour of rotating duct cleaning brushes.… (more)

▼

This thesis focuses on dust accumulation in, and removal from, recently installed supply air ducts and on the bristle behaviour of rotating duct cleaning brushes. The results of dust accumulation, measured using three different methods, were compared and the amount of dust in newly installed air ducts was evaluated. The vacuum test was found to be an efficient method of collecting dust samples on the duct surface. The vacuum test and the gravimetric tape method gave approximately the same results when the measured dust accumulation on the duct surfaces was 0.1-1.0 g/m2. The gravimetric and optical tape methods can be used to evaluate cleanliness of new ducts when the amount of dust accumulation is 0.1-1.0 g/m2. The effect of protection measures on dust accumulation was studied. The mean amount of accumulated dust after construction was 0.9 g/m2 in cleanliness category P1 ducts, which have special requirements for oil residues and protection measures against contamination during construction, and 2.3 g/m2 in cleanliness category P2 ducts, which have only minor protection requirements and are for normal use. The results show that dust accumulation in category P1 ducts was significantly lower (P < 0.008) than in category P2 ducts. The highest mean amount of dust accumulation was found in the middle of the ducts and the lowest amount near the air handling units. The efficiency of two dry air duct cleaning methods applied to new air ducts was compared. Mechanical brushing and compressed air cleaning methods were found to be efficient in removing dust from the newly installed air duct surfaces. Mechanical brushing was more efficient in metal ducts, while the compressed air cleaning method was more efficient in plastic ducts. The mean amount of residual dust on the duct surfaces was below 0.4 g/m2 after duct cleaning. However, neither of the cleaning methods studied was efficient enough to clean ducts that had a high level of residual oil (216-338 mg/m2) on the duct surfaces. A mathematical model to simulate the behaviour of a single bristle of a rotating duct cleaning brush was developed. The results of the simulation were compared with those obtained from a laboratory test. The simulated and experimental results were found to be in reasonable agreement. The dependence of the normal force and the contact angle as a function of various parameters was studied. The simulation and experimental results showed that the normal force and contact angle increase as a function of the rotation speed. Further, the thickness of the bristle was found to have a strong effect on the normal force. Air drag has only a slight effect on the deflection of the bristle. The model can be used as a first step in the systematic design of brushes. However, further theoretical and experimental research is needed to determine the dependency, for instance, between the brush tip normal force and its cleaning efficiency.

Report / Helsinki University of Technology, Laboratory of Heating, Ventilating and Air Conditioning. A, ISSN 1238-8971; 9

Advisors/Committee Members: Helsinki University of Technology, Department of Mechanical Engineering, Laboratory of Heating, Ventilating and Air Conditioning.

Subjects/Keywords: duct; dust; cleanliness categories; duct cleaning; bristle model; normal force; contact angle; air drag

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APA (6^th Edition):

Holopainen, R. (2004). Dust in Ventilation Ducts: Accumulation, Measurement and Removal. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2004/isbn9512269767/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Holopainen, Rauno. “Dust in Ventilation Ducts: Accumulation, Measurement and Removal.” 2004. Thesis, Helsinki University of Technology. Accessed January 24, 2021. http://lib.tkk.fi/Diss/2004/isbn9512269767/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Holopainen, Rauno. “Dust in Ventilation Ducts: Accumulation, Measurement and Removal.” 2004. Web. 24 Jan 2021.

Vancouver:

Holopainen R. Dust in Ventilation Ducts: Accumulation, Measurement and Removal. [Internet] [Thesis]. Helsinki University of Technology; 2004. [cited 2021 Jan 24]. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269767/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Holopainen R. Dust in Ventilation Ducts: Accumulation, Measurement and Removal. [Thesis]. Helsinki University of Technology; 2004. Available from: http://lib.tkk.fi/Diss/2004/isbn9512269767/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Ottawa

8. Asadollahi Shahbaboli, Nora. Numerical Modeling of Extreme Flow Impacts on Structures .

Degree: 2016, University of Ottawa

URL: http://hdl.handle.net/10393/35208

► Recent tsunami disasters caused devastating damages to well-engineered coastal infrastructures. In fact, the current design guidelines are not able to provide realistic estimations of tsunami… (more)

▼ Recent tsunami disasters caused devastating damages to well-engineered coastal infrastructures. In fact, the current design guidelines are not able to provide realistic estimations of tsunami loads in order to design structures to withstand tsunamis. Tsunami hydrodynamic forces are estimated using the drag coefficient. This coefficient is traditionally calculated based on a steady flow analogy. However, tsunami bores behave like unsteady flows. The present work aims at investigating the tsunami forces for different structure geometries to provide realistic guidelines to estimate drag coefficients considering unsteady flows. In the present paper, the dam-break approach is used to investigate the tsunami-like bore interaction with structures. A three-dimensional multiphase numerical model is implemented to study the tsunami induced forces on rectangular shape structures with various aspect ratios (width/depth) and orientations. The numerical model results are validated using measured forces and bore surface elevations of the physical experiments. A scaled-up domain is modeled in order to eliminate the effects of domain sidewalls in the simulation results. The drag coefficient relations with structure geometries and bore depths are provided. The obtained hydrodynamic forces and drag coefficients are compared with existing data in the literature and design codes. For the second topic, a multi-phase three-dimensional numerical reproduction of a large scale laboratory experiment of tsunami-like bores interaction with a surface-piercing circular column is presented. The numerical simulation is conducted in OpenFOAM. The dam-break mechanism is implemented in order to generate tsunami-like bores. The numerical model is validated using the experimental results performed at Canadian Hydraulics Center of the National Research Council (NRC-CHC) in Ottawa. The unsteady Reynolds Averaged Navier-Stokes equations (RANS) are used in order to treat the turbulence effects. The Shear Stress Transport (SST) k-ω turbulence model showed high level of accuracy in replication of the bore-structure interaction. Further, a scaled-up domain is used to investigate the influence of the bed condition in terms of various downstream depths and roughness. Finally, a broad investigation on the bore propagation characteristics is performed. The resulting stream-wise forces exerted on the structural column as well as the bore velocity are compared and analyzed for smooth, rough, dry and wet beds with varying depths.

Subjects/Keywords: Hydrodynamic force; Drag coefficient; Rectangular column; Aspect ratio; Structure orientation; Bed condition; Hydraulic bore; OpenFOAM

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Asadollahi Shahbaboli, N. (2016). Numerical Modeling of Extreme Flow Impacts on Structures . (Thesis). University of Ottawa. Retrieved from http://hdl.handle.net/10393/35208

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Asadollahi Shahbaboli, Nora. “Numerical Modeling of Extreme Flow Impacts on Structures .” 2016. Thesis, University of Ottawa. Accessed January 24, 2021. http://hdl.handle.net/10393/35208.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Asadollahi Shahbaboli, Nora. “Numerical Modeling of Extreme Flow Impacts on Structures .” 2016. Web. 24 Jan 2021.

Vancouver:

Asadollahi Shahbaboli N. Numerical Modeling of Extreme Flow Impacts on Structures . [Internet] [Thesis]. University of Ottawa; 2016. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/10393/35208.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Asadollahi Shahbaboli N. Numerical Modeling of Extreme Flow Impacts on Structures . [Thesis]. University of Ottawa; 2016. Available from: http://hdl.handle.net/10393/35208

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Robert Gordon University

9. Iyalla, Ibiyekariwaripiribo. Computational fluid dynamics modelling of pipeline on-bottom stability.

Degree: PhD, 2017, Robert Gordon University

URL: http://hdl.handle.net/10059/2721

► Subsea pipelines are subjected to wave and steady current loads which cause pipeline stability problems. Current knowledge and understanding on the pipeline on-bottom stability is… (more)

▼ Subsea pipelines are subjected to wave and steady current loads which cause pipeline stability problems. Current knowledge and understanding on the pipeline on-bottom stability is based on the research programmes from the 1980’s such as the Pipeline Stability Design Project (PIPESTAB) and American Gas Association (AGA) in Joint Industry Project. These projects have mainly provided information regarding hydrodynamic loads on pipeline and soil resistance in isolation. In reality, the pipeline stability problem is much more complex involving hydrodynamic loadings, pipeline response, soil resistance, embedment and pipe-soil-fluid interaction. In this thesis Computational Fluid Dynamics (CFD) modelling is used to investigate and establish the interrelationship between fluid (hydrodynamics), pipe (subsea pipeline), and soil (seabed). The effect of soil types, soil resistance, soil porosity and soil unit weight on embedment was examined. The overall pipeline stability alongside pipeline diameter and weight and hydrodynamic effect on both soil (resulting in scouring) and pipeline was also investigated. The use of CFD provided a better understanding of the complex physical processes of fluid-pipe-soil interaction. The results show that the magnitude of passive resistance is on the average eight times that of lateral resistance. Thus passive resistance is of greater significance for subsea pipeline stability design hence the reason why Coulomb’s friction theory is considered as conservative for stability design analysis, as it ignores passive resistance and underestimates lateral resistance. Previous works (such as that carried out by Lyons and DNV) concluded that soil resistance should be determined by considering Coulomb’s friction based on lateral resistance and passive resistance due to pipeline embedment, but the significance of passive resistance in pipeline stability and its variation in sand and clay soils have not be established as shown in this thesis. The results for soil porosity show that increase in pipeline stability with increasing porosity is due to increased soil liquefaction which increases soil resistance. The pipe-soil interaction model by Wagner et al. established the effect of soil porosity on lateral soil resistance but did not attribute it to soil liquefaction. Results showed that the effect of pipeline diameter and weight vary with soil type; for sand, pipeline diameter showed a greater influence on embedment with a 110% increase in embedment (considering combined effect of diameter and weight) and a 65% decrease in embedment when normalised with diameter. While pipeline weight showed a greater influence on embedment in clay with a 410% increase. The work of Gao et al. did not completely establish the combined effect of pipeline diameter and weight and soil type on stability. Results also show that pipeline instability is due to a combination of pipeline displacement due to vortex shedding and scouring effect with increasing velocity. As scoring progresses, maximum embedment is reached at the point of…

Subjects/Keywords: 620; Drag; Embedment; Hydrodynamic force; Lateral resistance; Lift; Passive resistance; Pipeline; Pressure coefficient; Scour; Stability

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Iyalla, I. (2017). Computational fluid dynamics modelling of pipeline on-bottom stability. (Doctoral Dissertation). Robert Gordon University. Retrieved from http://hdl.handle.net/10059/2721

Chicago Manual of Style (16^th Edition):

Iyalla, Ibiyekariwaripiribo. “Computational fluid dynamics modelling of pipeline on-bottom stability.” 2017. Doctoral Dissertation, Robert Gordon University. Accessed January 24, 2021. http://hdl.handle.net/10059/2721.

MLA Handbook (7^th Edition):

Iyalla, Ibiyekariwaripiribo. “Computational fluid dynamics modelling of pipeline on-bottom stability.” 2017. Web. 24 Jan 2021.

Vancouver:

Iyalla I. Computational fluid dynamics modelling of pipeline on-bottom stability. [Internet] [Doctoral dissertation]. Robert Gordon University; 2017. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/10059/2721.

Council of Science Editors:

Iyalla I. Computational fluid dynamics modelling of pipeline on-bottom stability. [Doctoral Dissertation]. Robert Gordon University; 2017. Available from: http://hdl.handle.net/10059/2721

Delft University of Technology

10. Schmidt, Annika (author). Viscosity Perception of Virtual Fluids rendered by a Hand Exoskeleton.

Degree: 2018, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:df9266f0-0684-4672-97ec-a2510f626cfb

►

—Enabling haptic interaction with non-solid materials, such as liquids or sediments, could expand possibilities for exploration of virtual or remote environments, which would e.g enable… (more)

Subjects/Keywords: human machine interaction; multi-finger force feedback; proprioception; drag forces; fluid dynamics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Schmidt, A. (. (2018). Viscosity Perception of Virtual Fluids rendered by a Hand Exoskeleton. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:df9266f0-0684-4672-97ec-a2510f626cfb

Chicago Manual of Style (16^th Edition):

Schmidt, Annika (author). “Viscosity Perception of Virtual Fluids rendered by a Hand Exoskeleton.” 2018. Masters Thesis, Delft University of Technology. Accessed January 24, 2021. http://resolver.tudelft.nl/uuid:df9266f0-0684-4672-97ec-a2510f626cfb.

MLA Handbook (7^th Edition):

Schmidt, Annika (author). “Viscosity Perception of Virtual Fluids rendered by a Hand Exoskeleton.” 2018. Web. 24 Jan 2021.

Vancouver:

Schmidt A(. Viscosity Perception of Virtual Fluids rendered by a Hand Exoskeleton. [Internet] [Masters thesis]. Delft University of Technology; 2018. [cited 2021 Jan 24]. Available from: http://resolver.tudelft.nl/uuid:df9266f0-0684-4672-97ec-a2510f626cfb.

Council of Science Editors:

Schmidt A(. Viscosity Perception of Virtual Fluids rendered by a Hand Exoskeleton. [Masters Thesis]. Delft University of Technology; 2018. Available from: http://resolver.tudelft.nl/uuid:df9266f0-0684-4672-97ec-a2510f626cfb

University of Cincinnati

11. Rontala Raghunathan, Ravi Shankar. In Vitro Measurement and Calculation of Drag Force on Aortic Stentgraft in a Compliant Arterial Wall Model.

Degree: MS, Engineering : Mechanical Engineering, 2006, University of Cincinnati

URL: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1163703097

► Interventional treatment of aortic aneurysms using endovascular stent grafting is a minimally invasive technique. Following device implantation, continuous hemodynamic forces are exerted (drag force) on… (more)

Subjects/Keywords: Abdominal aortic aneursym; drag force; stentgraft.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rontala Raghunathan, R. S. (2006). In Vitro Measurement and Calculation of Drag Force on Aortic Stentgraft in a Compliant Arterial Wall Model. (Masters Thesis). University of Cincinnati. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ucin1163703097

Chicago Manual of Style (16^th Edition):

Rontala Raghunathan, Ravi Shankar. “In Vitro Measurement and Calculation of Drag Force on Aortic Stentgraft in a Compliant Arterial Wall Model.” 2006. Masters Thesis, University of Cincinnati. Accessed January 24, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1163703097.

MLA Handbook (7^th Edition):

Rontala Raghunathan, Ravi Shankar. “In Vitro Measurement and Calculation of Drag Force on Aortic Stentgraft in a Compliant Arterial Wall Model.” 2006. Web. 24 Jan 2021.

Vancouver:

Rontala Raghunathan RS. In Vitro Measurement and Calculation of Drag Force on Aortic Stentgraft in a Compliant Arterial Wall Model. [Internet] [Masters thesis]. University of Cincinnati; 2006. [cited 2021 Jan 24]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1163703097.

Council of Science Editors:

Rontala Raghunathan RS. In Vitro Measurement and Calculation of Drag Force on Aortic Stentgraft in a Compliant Arterial Wall Model. [Masters Thesis]. University of Cincinnati; 2006. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1163703097

INP Toulouse

12. Chevrier, Solène. Development of subgrid models for a periodic circulating fluidized bed of binary mixture of particles : Développement de modèle de sous-maille pour la simulation numérique d'un écoulement polydisperse réactif.

Degree: Docteur es, Dynamique des fluides, 2017, INP Toulouse

URL: http://www.theses.fr/2017INPT0072

►

Des études numériques ont montré que la taille de la cellule de maillage peut avoir un effet drastique sur la modélisation du lit fluidisé circulant… (more)

▼

Des études numériques ont montré que la taille de la cellule de maillage peut avoir un effet drastique sur la modélisation du lit fluidisé circulant avec des petites particules. En effet, la taille de la cellule doit être de l’ordre de quelques diamètres de particules pour prédire avec précision le comportement dynamique d’un lit fluidisé. En conséquence, les simulations numériques d’ Euler-Euler des processus industriels sont généralement effectuées avec des grilles trop grossières pour permettre la prédiction des effets de ségrégation locale. La modélisation appropriée, qui prend en compte l’influence des structures non résolues, a déjà été proposée pour les simulations monodispersés. Dans ce travail, l’influence des structures non résolues sur un mélange binaire de particules est analysée et on propose des modèles pour tenir compte de cet effet dans des simulations de lit fluidisé polydispersés. Pour atteindre cet objectif, des simulations Euler-Euler de références sont réalisées avec un raffinement du maillage aboutissant à une solution indépendante de la taille de la cellule. Ce type de simulation numérique est très coûteux et se limite à des configurations très simples. Dans ce travail, la configuration se consiste en un lit circulant périodique 3D, qui représente la région établie d'un lit circulant. Parallèlement, une approche filtrée est développée où les termes inconnus, appelés contributions de sous-maille, doivent être modélisés. Les filtres spatiaux peuvent être appliqués aux résultats de simulation de référence afin de mesurer chaque contribution de sous-maille apparaissant dans l’approche théorique filtrée. Une analyse est réalisée afin de comprendre et de modéliser l’effet de la contribution des termes de sous-maille. L’opération de filtrage fait apparaître de nouveaux termes, les termes de sous-maille. Un terme filtré est la somme d’un terme résolu, obtenus à partir des champs filtrés, et d’ un terme de sous-maille. L’analyse de l’équation filtrée de quantité de mouvement montre que les contributions résolues de la traînée des particules fluides et la collision entre particules surestiment les effets de transferts de quantité de mouvement filtrés. L’analyse de l’équation filtrée de l’énergie cinétique des particules montre que la production résolue par le cisaillement moyen et par le mouvement relatif moyen des particules sous-estime contribution filtrée. Des modèles fonctionnels sont proposés pour les contributions de sous-maille de la traînée et des collisions inter-particule.

Detailed sensitivity numerical studies have shown that the mesh cell-size may have a drastic effect on the modelling of circulating fluidized bed with small particles. Typically, the cell-size must be of the order of few particle diameters to predict accurately the dynamical behaviour of a fluidized bed. Hence, the Euler-Euler numerical simulations of industrial processes are generally performed with grids too coarse to allow the prediction of the local segregation effects. Appropriate modelling, which takes into account…

Advisors/Committee Members: Simonin, Olivier (thesis director), Fede, Pascal (thesis director).

Subjects/Keywords: Lit fluidisé circulant; Modèle de sous mailles; Force de traînée; Collision; Chemical looping combustion; Fluidized beds; Subgrid models; Drag force; Collision

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Chevrier, S. (2017). Development of subgrid models for a periodic circulating fluidized bed of binary mixture of particles : Développement de modèle de sous-maille pour la simulation numérique d'un écoulement polydisperse réactif. (Doctoral Dissertation). INP Toulouse. Retrieved from http://www.theses.fr/2017INPT0072

Chicago Manual of Style (16^th Edition):

Chevrier, Solène. “Development of subgrid models for a periodic circulating fluidized bed of binary mixture of particles : Développement de modèle de sous-maille pour la simulation numérique d'un écoulement polydisperse réactif.” 2017. Doctoral Dissertation, INP Toulouse. Accessed January 24, 2021. http://www.theses.fr/2017INPT0072.

MLA Handbook (7^th Edition):

Chevrier, Solène. “Development of subgrid models for a periodic circulating fluidized bed of binary mixture of particles : Développement de modèle de sous-maille pour la simulation numérique d'un écoulement polydisperse réactif.” 2017. Web. 24 Jan 2021.

Vancouver:

Chevrier S. Development of subgrid models for a periodic circulating fluidized bed of binary mixture of particles : Développement de modèle de sous-maille pour la simulation numérique d'un écoulement polydisperse réactif. [Internet] [Doctoral dissertation]. INP Toulouse; 2017. [cited 2021 Jan 24]. Available from: http://www.theses.fr/2017INPT0072.

Council of Science Editors:

Chevrier S. Development of subgrid models for a periodic circulating fluidized bed of binary mixture of particles : Développement de modèle de sous-maille pour la simulation numérique d'un écoulement polydisperse réactif. [Doctoral Dissertation]. INP Toulouse; 2017. Available from: http://www.theses.fr/2017INPT0072

Delft University of Technology

13. Kamp, I.A. (author). Assessing the dynamic stability of a floating tidal energy platform during ballast operations.

Degree: 2015, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:e56db4c0-7c31-459d-9583-ccae162efb0e

►

A method is developed to assess the dynamic stability of a floating tidal energy platform during ballast operations. This method is applied to a tidal… (more)

Subjects/Keywords: renewables; mooring lines; lift force; drag force; changing waterline area; changing mass; 6 DOF; large amplitude rotations; MATLAB; Bluewater

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kamp, I. A. (. (2015). Assessing the dynamic stability of a floating tidal energy platform during ballast operations. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:e56db4c0-7c31-459d-9583-ccae162efb0e

Chicago Manual of Style (16^th Edition):

Kamp, I A (author). “Assessing the dynamic stability of a floating tidal energy platform during ballast operations.” 2015. Masters Thesis, Delft University of Technology. Accessed January 24, 2021. http://resolver.tudelft.nl/uuid:e56db4c0-7c31-459d-9583-ccae162efb0e.

MLA Handbook (7^th Edition):

Kamp, I A (author). “Assessing the dynamic stability of a floating tidal energy platform during ballast operations.” 2015. Web. 24 Jan 2021.

Vancouver:

Kamp IA(. Assessing the dynamic stability of a floating tidal energy platform during ballast operations. [Internet] [Masters thesis]. Delft University of Technology; 2015. [cited 2021 Jan 24]. Available from: http://resolver.tudelft.nl/uuid:e56db4c0-7c31-459d-9583-ccae162efb0e.

Council of Science Editors:

Kamp IA(. Assessing the dynamic stability of a floating tidal energy platform during ballast operations. [Masters Thesis]. Delft University of Technology; 2015. Available from: http://resolver.tudelft.nl/uuid:e56db4c0-7c31-459d-9583-ccae162efb0e

University of Alberta

14. Milne, Andrew J. B. Blown Away: The Shedding and Oscillation of Sessile Drops by Cross Flowing Air.

Degree: PhD, Department of Mechanical Engineering, 2013, University of Alberta

URL: https://era.library.ualberta.ca/files/2r36tz493

► For drops sessile on a solid surface, cross flowing air can drive drop oscillation or shedding, based on the balance and interaction of aerodynamic drag… (more)

▼ For drops sessile on a solid surface, cross flowing air can drive drop oscillation or shedding, based on the balance and interaction of aerodynamic drag force (based on drop size/shape and air speed) and adhesion/capillary forces (based on surface tension and drop size/shape). Better understanding of the above has applications to, e.g., fuel cell flooding, airfoil icing, and visibility in rain. To understand the basic physics, experiments studying individual sessile drops in a low speed wind tunnel were performed in this thesis. Analysis of high speed video gave time resolved profiles and airspeed for shedding. Testing 0.5 µl to 100 µl drops of water and hexadecane on poly(methyl methacrylate) PMMA, Teflon, and a superhydrophobic surface (SHS) yielded a master curve describing critical airspeed for shedding for water drops on all surface tested. This curve predicts behavior for new surfaces, and explains experimental results published previously. It also indicates that the higher contact angle leads to easier shedding due to decreased adhesion and increased drag. Developing a novel floating element differential drag sensor gave the first measurements of the microNewton drag force experienced by drops. Forces magnitude is comparable to gravitational shedding from a tilted plate and to simplified models for drop adhesion, with deviations that suggest effects due to the air flow. Fluid properties are seen to have little effect on drag versus airspeed, and decreased adhesion is seen to be more important than increased drag for easing shedding. The relation between drag coefficient and Reynolds number increases slightly with liquid-solid contact angle, and with drop volume. Results suggest that the drop experiences increased drag compared to similarly shaped solid bodies due to drop oscillations aeroelasticly coupling into the otherwise laminar flow. The bulk and surface oscillations of sessile drops in cross flow was also studied, using a full profile analysis technique to determine mode shapes. Oscillation frequency/mode shape is similar for cross flow and quiescent drops. The highest order models collected from the diffuse literature are seen to be reasonably accurate, except at maximum and minimum ranges of contact angle.

Subjects/Keywords: Drag Force; Pressure Gradient; Adhesion Force; Boundary Layer; Shear Sensor; Water; Poly(methyl methacrylate) PMMA; Hexadecane; Air Velocity; Cross Flowing Air; Reynolds Number; Oscillation; Floating Element; Incipient Motion; Contact Angle; Coefficient of Drag; Dispersion Relationship; Sessile Drop; Teflon; Laminar; Differential Drag; Superhydrophobic Surface

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Milne, A. J. B. (2013). Blown Away: The Shedding and Oscillation of Sessile Drops by Cross Flowing Air. (Doctoral Dissertation). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/2r36tz493

Chicago Manual of Style (16^th Edition):

Milne, Andrew J B. “Blown Away: The Shedding and Oscillation of Sessile Drops by Cross Flowing Air.” 2013. Doctoral Dissertation, University of Alberta. Accessed January 24, 2021. https://era.library.ualberta.ca/files/2r36tz493.

MLA Handbook (7^th Edition):

Milne, Andrew J B. “Blown Away: The Shedding and Oscillation of Sessile Drops by Cross Flowing Air.” 2013. Web. 24 Jan 2021.

Vancouver:

Milne AJB. Blown Away: The Shedding and Oscillation of Sessile Drops by Cross Flowing Air. [Internet] [Doctoral dissertation]. University of Alberta; 2013. [cited 2021 Jan 24]. Available from: https://era.library.ualberta.ca/files/2r36tz493.

Council of Science Editors:

Milne AJB. Blown Away: The Shedding and Oscillation of Sessile Drops by Cross Flowing Air. [Doctoral Dissertation]. University of Alberta; 2013. Available from: https://era.library.ualberta.ca/files/2r36tz493

Harvard University

15. Lucas, Kelsey Noelle. Physical Mechanisms of Force Production for Swimming in Fishes.

Degree: PhD, 2019, Harvard University

URL: http://nrs.harvard.edu/urn-3:HUL.InstRepos:42029628

► Fishes must swim effectively to perform many behaviors that are important for evolutionary fitness. So, understanding how a fish’s body morphology, mechanical properties, and movements… (more)

▼ Fishes must swim effectively to perform many behaviors that are important for evolutionary fitness. So, understanding how a fish’s body morphology, mechanical properties, and movements combine to enable swimming can provide insight into the evolution of their present body forms. Here, I use physical models and experimental fluid dynamics to study the relationships between fish body properties and swimming performance. The first section of this dissertation centers on the contributions the body’s flexural stiffness makes to overall swimming performance. In my previous work, I found that many swimming and flying animals, including fishes, bend their bodies and appendages in a similar way during steady locomotion in part due to non-uniform flexural stiffness in their propulsive structures. In Chapter 1, I use a simple physical modeling system to isolate the effects of flexural stiffness from the complexity of a fish body. Using versions of the simple model with different flexural stiffnesses, I show that having non-uniform stiffness along the body length leads to faster, more efficient swimming. I extend these results in Appendix I, where I compare several tuna-tail-shaped models of different stiffnesses and find that certain combinations of stiffness and fish-like movements improves swimming ability. The findings indicate that the non-uniform physical properties of different components of a fish’s body are paramount for maintaining high overall swimming performance, and I hypothesize that fish may be controlling their body stiffness and movements to achieve performance benefits. In the second section of my dissertation, I focus on how the fish’s body interacts with the surrounding water to create swimming forces. In the past, our understanding of these interactions has been limited by the difficulty of measuring forces in a fluid medium. Therefore, in Chapter 2, I develop and validate new tools that allow me to estimate these forces at high spatial and temporal resolution using a pressure-based approach. I then apply these tools in Chapter 3 to describe how carangiform swimmers – fishes swimming using only their bodies and caudal fins and undulate only the posterior portion of the body at large amplitudes – generate swimming forces. I find that both positive and negative pressure contribute to thrust and drag. Further, in contrast to previous hypotheses, I find that carangiform fishes generate both thrust and drag along much of the length of their bodies in complex temporal patterns. I conclude by describing how subtle differences between different carangiform swimmers’ movements and body shape lead to significant differences in force production. Taken together, my results suggest that fishes may simultaneously use a variety of mechanisms to produce swimming forces, and identifies specific body features and movements which dictate swimming abilities. Future work will continue to explore the relationships between body morphology, material properties, and swimming abilities, and to apply this knowledge… Advisors/Committee Members: Tytell, Eric (advisor), Biewener, Andrew (committee member), Holbrook, N. Michele (committee member).

Subjects/Keywords: fish; fishes; swimming; biomechanics; biofluid dynamics; biological fluid dynamics; body stiffness; flexural stiffness; flapping foils; hydrofoils; force; pressure; pressure-based force calculation; force calculation; swimming forces; thrust; drag

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lucas, K. N. (2019). Physical Mechanisms of Force Production for Swimming in Fishes. (Doctoral Dissertation). Harvard University. Retrieved from http://nrs.harvard.edu/urn-3:HUL.InstRepos:42029628

Chicago Manual of Style (16^th Edition):

Lucas, Kelsey Noelle. “Physical Mechanisms of Force Production for Swimming in Fishes.” 2019. Doctoral Dissertation, Harvard University. Accessed January 24, 2021. http://nrs.harvard.edu/urn-3:HUL.InstRepos:42029628.

MLA Handbook (7^th Edition):

Lucas, Kelsey Noelle. “Physical Mechanisms of Force Production for Swimming in Fishes.” 2019. Web. 24 Jan 2021.

Vancouver:

Lucas KN. Physical Mechanisms of Force Production for Swimming in Fishes. [Internet] [Doctoral dissertation]. Harvard University; 2019. [cited 2021 Jan 24]. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:42029628.

Council of Science Editors:

Lucas KN. Physical Mechanisms of Force Production for Swimming in Fishes. [Doctoral Dissertation]. Harvard University; 2019. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:42029628

University of Manchester

16. Mendez Mendez, Juan. Mechanical properties of single keloid and normal skin fibroblast measured using an atomic force microscope.

Degree: 2010, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:82884

► The human body consists of a number of very complex, highly specialised organs which perform a variety of functions that are essential to life and… (more)

▼ The human body consists of a number of very complex, highly specialised organs which perform a variety of functions that are essential to life and health. One of the main functions of the skin, the largest of the human organs, is to maintain the integrity of the body. It does this by acting as a physical barrier, preventing micro-organisms and other potentially harmful substances from entering the body. When the integrity of the skin is damaged through injury, a self-protective mechanism is triggered and the reparative wound healing process begins. Under normal circumstances the wound healing process culminates in the skin recuperating its normal characteristics and functions at the site of the injury, with only a small visible mark being left behind. However, in some cases the wound healing process may become altered leading to the production of abnormal scars, such as keloids. Keloid scars are formed from scar tissue at the site of an injury, as a result of excessive tissue repair that extends beyond the boundaries of the original wound. These scars are characterised by excess collagen deposition produced during the wound healing process. It is estimated that as many as 20% of the black and Hispanic population are affected by keloid scarring. In addition to the aesthetic aspect, keloid scars can also be painful, itchy and prone to become infected. Keloid scar formation can be triggered by skin injuries caused by, for example, acne, wounds, shaving, burns, and surgical incisions. The mechanism by which keloid scars form is currently not well understood and consequently no effective treatments exist to date.This thesis describes an investigation into the mechanical properties of single keloid and normal skin fibroblast cells for the purpose of establishing if there is a quantitative difference between the two types of cells. This information will be of benefit to researchers looking for a better understanding of the keloid formation mechanism and for those seeking improved treatments. An atomic force microscope (AFM) was employed to indent single Keloid and normal skin fibroblast cells taken from five patients. Values for the apparent Young’s modulus of the cells were then calculated by fitting the experimental data using Hertz’s model. Apparent Young’s modulus values were then compared. The findings of the analysis indicate that statistically, there is a significant difference in the Young’s modulus values of normal and keloid cells, with keloid cells exhibiting substantially greater stiffness than normal skin fibroblast cells. To enable the keloid and normal skin fibroblast cells to be studied in as close to their natural, physiological environment as is possible the AFM experiments described in this thesis were undertaken in a phosphate buffered saline (PBS) solution. In such cases the use of a fluid medium presents additional complexities, not least of which is the introduction of a hydrodynamic drag force due to viscous friction of the cantilever with the liquid which can affect the experimental data obtained… Advisors/Committee Members: Alonso Rasgado, Teresa.

Subjects/Keywords: AFM; Keloid scar; keloid cell; fibroblast; Drag force; FEM

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Mendez Mendez, J. (2010). Mechanical properties of single keloid and normal skin fibroblast measured using an atomic force microscope. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:82884

Chicago Manual of Style (16^th Edition):

Mendez Mendez, Juan. “Mechanical properties of single keloid and normal skin fibroblast measured using an atomic force microscope.” 2010. Doctoral Dissertation, University of Manchester. Accessed January 24, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:82884.

MLA Handbook (7^th Edition):

Mendez Mendez, Juan. “Mechanical properties of single keloid and normal skin fibroblast measured using an atomic force microscope.” 2010. Web. 24 Jan 2021.

Vancouver:

Mendez Mendez J. Mechanical properties of single keloid and normal skin fibroblast measured using an atomic force microscope. [Internet] [Doctoral dissertation]. University of Manchester; 2010. [cited 2021 Jan 24]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:82884.

Council of Science Editors:

Mendez Mendez J. Mechanical properties of single keloid and normal skin fibroblast measured using an atomic force microscope. [Doctoral Dissertation]. University of Manchester; 2010. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:82884

Université de Lorraine

17. Ouchene, Rafik. Dispersion de particules non-sphériques en écoulement turbulent : Dispersion of non spherical particles in a turbulent flow.

Degree: Docteur es, Mécanique et énergétique, 2015, Université de Lorraine

URL: http://www.theses.fr/2015LORR0275

►

Ce travail de thèse fait partie intégrante de l’ANR PLAYER (début janvier 2012), projet visant à étendre les simulations d'écoulements gaz-particules à des particules non-sphériques… (more)

▼

Ce travail de thèse fait partie intégrante de l’ANR PLAYER (début janvier 2012), projet visant à étendre les simulations d'écoulements gaz-particules à des particules non-sphériques ayant une inertie couvrant une large gamme. Les avancées de cette ANR portent notamment sur la détermination des forces et couples élémentaires sur de tels objets avec la question du nombre de degrés de liberté supplémentaires à prendre en compte, l'impact de la forme et de l’effet d'inertie ainsi que l’influence d’une force extérieure telle que la gravité sur les interactions particule-turbulence. Dans ce cadre, l’objectif de ce travail de thèse est d'étudier finement la dispersion de particules non-sphériques rigides dans un écoulement turbulent à l’échelle mésocospique (il est supposé que les particules sont des points matériels). Pour ce faire, un suivi lagrangien de particules ellipsoïdales couplé à un code de simulation numérique directe d’un écoulement turbulent de canal a été utilisé. Cette méthode nécessite alors une bonne estimation des forces et couples hydrodynamiques agissant sur ce type de particules, ainsi qu’un couplage des équations du mouvement de translation et de rotation. En se basant sur les résultats obtenus par une simulation numérique directe résolue à l’échelle de la particule (Ansys Fluent, body-fitted method), nous avons établi, dans un premier temps, des corrélations pour les coefficients hydrodynamiques (traînée, portance, couple de tangage) dépendant du nombre de Reynolds particulaire, de la forme, et de l'orientation des particules. L’originalité de ce travail réside en la validité de ces corrélations pour des gammes étendues de facteurs de forme (rapport entre la longueur et la largeur de la particule w ∈ [0,2-32] et de Reynolds particulaires Rep ∈ [1-240]. Ces corrélations ainsi que les équations du mouvement de rotation ont été ensuite intégrées dans le code « maison » de simulation numérique directe d’un écoulement turbulent gaz-solide à l’échelle mésocospique. Après avoir validé ce code à travers différents cas tests, nous avons étudié la dispersion de différentes particules ellipsoïdales dans un écoulement de canal turbulent pour un nombre de Reynolds modéré. Trois principaux effets sont à l’étude : l’effet de forme, l'effet d'inertie et l'effet du croisement de trajectoires.

The present work is a part of a program research ANR PLAYER (started from January 2012), the aim of the project is to extend the simulations of gaz-particles flow to the non-spherical particles with a large range of inertia. The main objectives of this project consist, firstly, on the founding of hydrodynamic forces and torques occurring on these non-spherical particles. As results, we focus on the additional degrees of freedom that must be considered, shape effects and effects of inertia. Secondly, we are interested on the study of particle-turbulence interaction and particle-particle interaction. The aim of this Phd thesis consists on the studying of the dispersion of solide non-spherical particles in turbulent channel flow…

Advisors/Committee Members: Tanière, Anne (thesis director), Khalij, Mohamed (thesis director).

Subjects/Keywords: Force hydrodynamique; Traînée; Portance; Couple; Particules ellipsoïdales; DNS; Turbulence; Dispersion; Hydrodynamic forces; Drag; Lift; Torque; Ellipsoidal particles; DNS; Turbulence; Dispersion; 532.5

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ouchene, R. (2015). Dispersion de particules non-sphériques en écoulement turbulent : Dispersion of non spherical particles in a turbulent flow. (Doctoral Dissertation). Université de Lorraine. Retrieved from http://www.theses.fr/2015LORR0275

Chicago Manual of Style (16^th Edition):

Ouchene, Rafik. “Dispersion de particules non-sphériques en écoulement turbulent : Dispersion of non spherical particles in a turbulent flow.” 2015. Doctoral Dissertation, Université de Lorraine. Accessed January 24, 2021. http://www.theses.fr/2015LORR0275.

MLA Handbook (7^th Edition):

Ouchene, Rafik. “Dispersion de particules non-sphériques en écoulement turbulent : Dispersion of non spherical particles in a turbulent flow.” 2015. Web. 24 Jan 2021.

Vancouver:

Ouchene R. Dispersion de particules non-sphériques en écoulement turbulent : Dispersion of non spherical particles in a turbulent flow. [Internet] [Doctoral dissertation]. Université de Lorraine; 2015. [cited 2021 Jan 24]. Available from: http://www.theses.fr/2015LORR0275.

Council of Science Editors:

Ouchene R. Dispersion de particules non-sphériques en écoulement turbulent : Dispersion of non spherical particles in a turbulent flow. [Doctoral Dissertation]. Université de Lorraine; 2015. Available from: http://www.theses.fr/2015LORR0275

Cranfield University

18. Sibilli, Thierry. Modelling the aerodynamics of propulsive system integration at cruise and high-lift conditions.

Degree: PhD, 2012, Cranfield University

URL: http://dspace.lib.cranfield.ac.uk/handle/1826/7945

► Due to a trend towards Ultra High Bypass Ratio engines the corresponding engine/airframe interference is becoming a key aspect in aircraft design. The present economic… (more)

▼ Due to a trend towards Ultra High Bypass Ratio engines the corresponding engine/airframe interference is becoming a key aspect in aircraft design. The present economic situation increases the pressure on commercial aviation companies to reduce the Direct Operating Cost, and the environmental situation requires a new generation of aircraft with a lower environmental impact. Therefore detailed aerodynamic investigations are required to evaluate the real benefits of new technologies. The presented research activity is part of a long-term project with the main objective of generating a reliable and accurate tool to predict the performance of an aircraft over the whole flight domain. In particular the aim of this research was to perform advanced CFD in order to establish a tool able to evaluate engine installation effects for different configurations and attitudes. The developed tool can be provided with correlations of the Net Propulsive Force (NPF), the force exerted by the power-plant to the aircraft, as a function of position. This can be done in principle at cruise, hold, climb, descent, take-off and landing, to model the different integration effects at different phases. Due to the complexity of the problem it was only possible at an initial stage to determine these correlations at cruise condition. Two parametric test cases were evaluated, showing that the engine horizontal positioning can influence the mission fuel burn by up to 6.4%. According to the extensive literature review that has been done, this study can be regarded as the first open literature engine position-NPF parametric study using CFD. Even though no correlations were extracted for other conditions; a deployed high-lift wing configuration was also studied in detail, defining the main aerodynamics effects of the engine integration at high angle of attack. A topological study of the high-lift installation vortices is presented in this work and it can be considered the first in the open literature. It should be pointed out that extensive research is currently underway to correctly evaluate the high-lift aerodynamic using CFD. The Propulsive System Integration (PSI) in high-lift conditions is adding flow features to an already demanding problem, making it a real challenge for the numerical methods. Nevertheless the additional effects of a nacelle chine on the maximum lift were also evaluated. The main outcomes of this PhD research were: a coupled performance modelling tool able to handle the effects of engine-airframe integration as a function of geometry and attitude, and a topological study of the high-lift installation vortices. During the course of the work, this research was successfully suggested as an extra activity for the European NEWAC project (New Aero Engine Core Concepts), and resulted in a new deliverable for that project.

Subjects/Keywords: Engine-Airframe Interaction; Net Propulsive Force; High-Lift CFD; High-lift Installation Vortex; Nacelle chine; Drag Extraction

Record Details Similar Records Cite « Share

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Sibilli, T. (2012). Modelling the aerodynamics of propulsive system integration at cruise and high-lift conditions. (Doctoral Dissertation). Cranfield University. Retrieved from http://dspace.lib.cranfield.ac.uk/handle/1826/7945

Chicago Manual of Style (16^th Edition):

Sibilli, Thierry. “Modelling the aerodynamics of propulsive system integration at cruise and high-lift conditions.” 2012. Doctoral Dissertation, Cranfield University. Accessed January 24, 2021. http://dspace.lib.cranfield.ac.uk/handle/1826/7945.

MLA Handbook (7^th Edition):

Sibilli, Thierry. “Modelling the aerodynamics of propulsive system integration at cruise and high-lift conditions.” 2012. Web. 24 Jan 2021.

Vancouver:

Sibilli T. Modelling the aerodynamics of propulsive system integration at cruise and high-lift conditions. [Internet] [Doctoral dissertation]. Cranfield University; 2012. [cited 2021 Jan 24]. Available from: http://dspace.lib.cranfield.ac.uk/handle/1826/7945.

Council of Science Editors:

Sibilli T. Modelling the aerodynamics of propulsive system integration at cruise and high-lift conditions. [Doctoral Dissertation]. Cranfield University; 2012. Available from: http://dspace.lib.cranfield.ac.uk/handle/1826/7945

Cranfield University

19. Sibilli, Thierry. Modelling the aerodynamics of propulsive system integration at cruise and high-lift conditions.

Degree: PhD, 2012, Cranfield University

URL: http://dspace.lib.cranfield.ac.uk/handle/1826/7945 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.573646

► Due to a trend towards Ultra High Bypass Ratio engines the corresponding engine/airframe interference is becoming a key aspect in aircraft design. The present economic… (more)

▼ Due to a trend towards Ultra High Bypass Ratio engines the corresponding engine/airframe interference is becoming a key aspect in aircraft design. The present economic situation increases the pressure on commercial aviation companies to reduce the Direct Operating Cost, and the environmental situation requires a new generation of aircraft with a lower environmental impact. Therefore detailed aerodynamic investigations are required to evaluate the real benefits of new technologies. The presented research activity is part of a long-term project with the main objective of generating a reliable and accurate tool to predict the performance of an aircraft over the whole flight domain. In particular the aim of this research was to perform advanced CFD in order to establish a tool able to evaluate engine installation effects for different configurations and attitudes. The developed tool can be provided with correlations of the Net Propulsive Force (NPF), the force exerted by the power-plant to the aircraft, as a function of position. This can be done in principle at cruise, hold, climb, descent, take-off and landing, to model the different integration effects at different phases. Due to the complexity of the problem it was only possible at an initial stage to determine these correlations at cruise condition. Two parametric test cases were evaluated, showing that the engine horizontal positioning can influence the mission fuel burn by up to 6.4%. According to the extensive literature review that has been done, this study can be regarded as the first open literature engine position-NPF parametric study using CFD. Even though no correlations were extracted for other conditions; a deployed high-lift wing configuration was also studied in detail, defining the main aerodynamics effects of the engine integration at high angle of attack. A topological study of the high-lift installation vortices is presented in this work and it can be considered the first in the open literature. It should be pointed out that extensive research is currently underway to correctly evaluate the high-lift aerodynamic using CFD. The Propulsive System Integration (PSI) in high-lift conditions is adding flow features to an already demanding problem, making it a real challenge for the numerical methods. Nevertheless the additional effects of a nacelle chine on the maximum lift were also evaluated. The main outcomes of this PhD research were: a coupled performance modelling tool able to handle the effects of engine-airframe integration as a function of geometry and attitude, and a topological study of the high-lift installation vortices. During the course of the work, this research was successfully suggested as an extra activity for the European NEWAC project (New Aero Engine Core Concepts), and resulted in a new deliverable for that project.

Subjects/Keywords: 629.132; Engine-Airframe Interaction; Net Propulsive Force; High-Lift CFD; High-lift Installation Vortex; Nacelle chine; Drag Extraction

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Sibilli, T. (2012). Modelling the aerodynamics of propulsive system integration at cruise and high-lift conditions. (Doctoral Dissertation). Cranfield University. Retrieved from http://dspace.lib.cranfield.ac.uk/handle/1826/7945 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.573646

Chicago Manual of Style (16^th Edition):

Sibilli, Thierry. “Modelling the aerodynamics of propulsive system integration at cruise and high-lift conditions.” 2012. Doctoral Dissertation, Cranfield University. Accessed January 24, 2021. http://dspace.lib.cranfield.ac.uk/handle/1826/7945 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.573646.

MLA Handbook (7^th Edition):

Sibilli, Thierry. “Modelling the aerodynamics of propulsive system integration at cruise and high-lift conditions.” 2012. Web. 24 Jan 2021.

Vancouver:

Sibilli T. Modelling the aerodynamics of propulsive system integration at cruise and high-lift conditions. [Internet] [Doctoral dissertation]. Cranfield University; 2012. [cited 2021 Jan 24]. Available from: http://dspace.lib.cranfield.ac.uk/handle/1826/7945 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.573646.

Council of Science Editors:

Sibilli T. Modelling the aerodynamics of propulsive system integration at cruise and high-lift conditions. [Doctoral Dissertation]. Cranfield University; 2012. Available from: http://dspace.lib.cranfield.ac.uk/handle/1826/7945 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.573646

Delft University of Technology

20. Drost, Lisanne (author). The Submerged Floating Tunnel: An experimental study on the hydrodynamics and kinematics of a submerged rectangular cylinder in a wave-current environment.

Degree: 2019, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:91a1c1bf-474b-4952-9485-c53f2fe353f0

► This study presents the results of small scale flume experiments on a submerged rectangular cylinder subjected to a current, regular wave and combined wave-current environment.… (more)

▼ This study presents the results of small scale flume experiments on a submerged rectangular cylinder subjected to a current, regular wave and combined wave-current environment. The objective of the study is to gain more knowledge about the hydrodynamics around and the kinematics of a submerged structure, to give a contribute to the research field of the submerged floating tunnel. For this study a rectangular cylinder with an aspect ratio (breadth-depth) of 2.5 is used. Two relative submergence depths (flume depth/model submergence) of 2.75 and 1.63 are tested. For all tests a still water depth of 0.7 m is applied. Waves resulting in very low KC numbers of <1 for regular waves and KC[1+U_c/U_m ]<2 for combined waves-current are generated. To create a combined wave-current environment, a current is created in the flume, to which waves are added by the wave generator. The water velocity is measured in front of the model. To approximate the water velocity at the model, a time/phase shift is added to the velocity signal. Linear wave theory is applied to approximate the amplitudes of the orbital velocities at the depth of the model. For the first part of the study, on the hydrodynamic forces, the cylinder is rigidly fixed in the flume. Due to the inertia dominance for low KC numbers, the relationship between the wave parameters and the hydrodynamic forces is well described by the relationship between the wave parameters and the water particle accelerations. The vertical hydrodynamic forces are found to be larger than the horizontal hydrodynamic forces. The force coefficients from this study are compared to coefficient found in previous studies. The drag coefficients for the only current tests agree well with the results from (Courchesne & Laneville, 1979), (Bearman & Trueman, 1972), (Nakaguchi, 1968) and (Venugopal, 2006). For the regular wave and combined wave-current conditions comparable results are found to those by Venugopal for a rectangular cylinder towed through a wave field (Venugopal, 2008). The drag coefficients in the present study show a similar trend in magnitude as in the study by Venugopal. However, the magnitudes have an opposite sign due to the velocity phase shift method applied in the present study. Nevertheless, the effect of this difference on the total force prediction is insignificant, because of inertia dominance. In general, the Morison equation predicts the measured horizontal force well for regular waves. Adding a current component to the waves results in a larger error between the computed Morison forces and the measured force. However, an increase in the magnitude of the added velocity does not lead to a significant increase of this error. The second part of the study focuses on the same cylinder, only not fixed but held in place by 4 tethers. For these tests a buoyancy to weight ratio of 1.5 is applied. The used tested angles between the tethers and the flume bottom are 30˚ and 70 ̊. The water depth, the wave types and model submergence depths are remained equal to the first… Advisors/Committee Members: Uijttewaal, Wim (mentor), Chen, Xuexue (graduation committee), Peters, Dirk Jan (graduation committee), Reinders, Kristina (graduation committee), Delft University of Technology (degree granting institution).

Subjects/Keywords: wave-current interaction; drag forces; intertia forces; rectangle; tether; submerged floating tunnel; Hydrodynamic; Morison's equation; Experimental; force coëfficients; kinematics; displacments; accelerations

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Drost, L. (. (2019). The Submerged Floating Tunnel: An experimental study on the hydrodynamics and kinematics of a submerged rectangular cylinder in a wave-current environment. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:91a1c1bf-474b-4952-9485-c53f2fe353f0

Chicago Manual of Style (16^th Edition):

Drost, Lisanne (author). “The Submerged Floating Tunnel: An experimental study on the hydrodynamics and kinematics of a submerged rectangular cylinder in a wave-current environment.” 2019. Masters Thesis, Delft University of Technology. Accessed January 24, 2021. http://resolver.tudelft.nl/uuid:91a1c1bf-474b-4952-9485-c53f2fe353f0.

MLA Handbook (7^th Edition):

Drost, Lisanne (author). “The Submerged Floating Tunnel: An experimental study on the hydrodynamics and kinematics of a submerged rectangular cylinder in a wave-current environment.” 2019. Web. 24 Jan 2021.

Vancouver:

Drost L(. The Submerged Floating Tunnel: An experimental study on the hydrodynamics and kinematics of a submerged rectangular cylinder in a wave-current environment. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Jan 24]. Available from: http://resolver.tudelft.nl/uuid:91a1c1bf-474b-4952-9485-c53f2fe353f0.

Council of Science Editors:

Drost L(. The Submerged Floating Tunnel: An experimental study on the hydrodynamics and kinematics of a submerged rectangular cylinder in a wave-current environment. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:91a1c1bf-474b-4952-9485-c53f2fe353f0

Brno University of Technology

21. Poláš, Maroš. Experimentální identifikace aerodynamických vlastností vozidla jízdní zkouškou: Experimental identification of aerodynamic characteristics of a vehicle by on-road test.

Degree: 2019, Brno University of Technology

URL: http://hdl.handle.net/11012/66535

► This thesis deals with road loads, coastdown tests and evaluation of measured data. Thesis consists of two main parts: theoretical and computational. The first part… (more)

Subjects/Keywords: aerodynamická odporová sila; vztlaková sila; aerodynamika; dojazdová skúška; Matlab; aerodynamic drag; lift force; aerodynamics; coastdown test; Matlab

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Poláš, M. (2019). Experimentální identifikace aerodynamických vlastností vozidla jízdní zkouškou: Experimental identification of aerodynamic characteristics of a vehicle by on-road test. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/66535

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Poláš, Maroš. “Experimentální identifikace aerodynamických vlastností vozidla jízdní zkouškou: Experimental identification of aerodynamic characteristics of a vehicle by on-road test.” 2019. Thesis, Brno University of Technology. Accessed January 24, 2021. http://hdl.handle.net/11012/66535.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Poláš, Maroš. “Experimentální identifikace aerodynamických vlastností vozidla jízdní zkouškou: Experimental identification of aerodynamic characteristics of a vehicle by on-road test.” 2019. Web. 24 Jan 2021.

Vancouver:

Poláš M. Experimentální identifikace aerodynamických vlastností vozidla jízdní zkouškou: Experimental identification of aerodynamic characteristics of a vehicle by on-road test. [Internet] [Thesis]. Brno University of Technology; 2019. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/11012/66535.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Poláš M. Experimentální identifikace aerodynamických vlastností vozidla jízdní zkouškou: Experimental identification of aerodynamic characteristics of a vehicle by on-road test. [Thesis]. Brno University of Technology; 2019. Available from: http://hdl.handle.net/11012/66535

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

22. Da silva Rodrigues, Sofia. Riser hydrodynamic study with Group B particles for Chemical Looping Combustion : Étude hydrodynamique du riser avec des particules du groupe B pour la Combustion en Boucle Chimique.

Degree: Docteur es, Procédés, 2014, Université Claude Bernard – Lyon I

URL: http://www.theses.fr/2014LYO10230

►

La combustion en boucle chimique (CLC) est un procédé du type oxy-combustion où des particules sont utilisées pour fournir de l'oxygène à la combustion. Des… (more)

▼

La combustion en boucle chimique (CLC) est un procédé du type oxy-combustion où des particules sont utilisées pour fournir de l'oxygène à la combustion. Des études sont nécessaires pour l'extrapolation et l'optimisation du procédé CLC, fonction des propriétés des particules du groupe B et de la technologie CFB. Les études hydrodynamiques ont été faites dans un riser de 18 m de hauteur. Des profils axiaus de pression, ainsi que les profils radiaux de flux et de quantité de mouvement ont été obtenus. Trois types de particules ont été utilisées ayant un diamètre de Sauter entre 250 et 300 μm et une densité entre 2600 et 3300 kg/ m3. Un impact de la sphéricité des particules sur la perte de charge a été révélé. Dans des conditions identiques, les billes de verre génèrent des pertes de charge d'environ 50% inférieures à celles du sable. Dans la zone d'écoulement développée, la présence du régime cœur-anneau a été détectée. Un modèle hydrodynamique 1D du riser qui est à la fois fondé sur des données expérimentales et sur les équations gaz-solide Euler-Euler, a été développé. Une nouvelle corrélation pour la force de traînée moyennée sur la section est proposée. Une nouvelle corrélation des conditions limite dans la partie inférieure du riser a aussi été établie. Le modèle 1D final est en mesure de prédire la perte de charge du riser pour différentes conditions opératoires et en tenant compte des propriétés des particules, comme la densité, la taille et la forme. Une étude sur la pertinence de l'utilisation du logiciel Barracuda CPFD® pour simuler des particules du groupe B en régime de transport a été réalisée. Il a été montré que le code sous-estime la perte de charge pour le sable

Chemical Looping Combustion (CLC) is an oxy-combustion like process where particles are used to supply oxygen to combustion. Further work is still needed for extrapolation and optimization of the CLC process, concerning properties of Group B particles and CFB technology. Hydrodynamic tests were made on a 18 m tall riser. Axial pressure profiles as well as radial flux profiles and radial momentum quantity profiles were obtained. Three types of Group B particles were used with Sauter mean diameters between 250 and 300 μm and densities between 2600 and 3300 kg/m²s. An important impact of particle sphericity on riser pressure drop has been revealed. At identical conditions, glass beads present about half the pressure drop generated by sand. In the developed region of the riser, the core-annulus regime has been found. A 1D model of the riser, based on experimental results and on the Euler-Euler gas-solid equations, has been developed. Moreover, a new cross section averaged drag force correlation is presented. A new boundary condition on the bottom of the riser has been investigated. The final 1D model is capable of predicted riser pressure drop from the operating conditions and it takes into account particle properties such as density, size and shape. A study on the adequacy of the use of the commercial CFD code Barracuda to simulate risers with…

Advisors/Committee Members: Gauthier, Thierry (thesis director).

Subjects/Keywords: Lit fluidisé circulant; Particules groupe B; Riser; Force de traînée; Modèle 1D; CFD; Circulating fluidized bed; Group B; Riser; Drag force; 1D model; Computational Fluid Dynamics; 541.361

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APA (6^th Edition):

Da silva Rodrigues, S. (2014). Riser hydrodynamic study with Group B particles for Chemical Looping Combustion : Étude hydrodynamique du riser avec des particules du groupe B pour la Combustion en Boucle Chimique. (Doctoral Dissertation). Université Claude Bernard – Lyon I. Retrieved from http://www.theses.fr/2014LYO10230

Chicago Manual of Style (16^th Edition):

Da silva Rodrigues, Sofia. “Riser hydrodynamic study with Group B particles for Chemical Looping Combustion : Étude hydrodynamique du riser avec des particules du groupe B pour la Combustion en Boucle Chimique.” 2014. Doctoral Dissertation, Université Claude Bernard – Lyon I. Accessed January 24, 2021. http://www.theses.fr/2014LYO10230.

MLA Handbook (7^th Edition):

Da silva Rodrigues, Sofia. “Riser hydrodynamic study with Group B particles for Chemical Looping Combustion : Étude hydrodynamique du riser avec des particules du groupe B pour la Combustion en Boucle Chimique.” 2014. Web. 24 Jan 2021.

Vancouver:

Da silva Rodrigues S. Riser hydrodynamic study with Group B particles for Chemical Looping Combustion : Étude hydrodynamique du riser avec des particules du groupe B pour la Combustion en Boucle Chimique. [Internet] [Doctoral dissertation]. Université Claude Bernard – Lyon I; 2014. [cited 2021 Jan 24]. Available from: http://www.theses.fr/2014LYO10230.

Council of Science Editors:

Da silva Rodrigues S. Riser hydrodynamic study with Group B particles for Chemical Looping Combustion : Étude hydrodynamique du riser avec des particules du groupe B pour la Combustion en Boucle Chimique. [Doctoral Dissertation]. Université Claude Bernard – Lyon I; 2014. Available from: http://www.theses.fr/2014LYO10230

Delft University of Technology

23. ter Meulen, Gijs (author). Draghead Analysis: An analysis of the draghead's physical processes to determine the trailing forces and the production.

Degree: 2018, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:f9d91312-4748-4218-a616-273d332aa943

► In dredging there are a lot of opportunities to improve the production processes and to make the production cycle more efficient, especially the excavation process… (more)

▼ In dredging there are a lot of opportunities to improve the production processes and to make the production cycle more efficient, especially the excavation process of the draghead. The aim of this research is to determine the trailing forces and to estimate the production of the draghead. Besides that, the goal is to get more insight into how the draghead behaves, depending on the trailing velocities. The variations in the trailing velocities, soil characteristics, control settings and draghead and suction pipe geometries that can occur do not make it easy to determine the trailing forces on the draghead and suction pipe. Because of this complexity, it is also hard to define how to estimate the production. Therefore, the scope of this research is limited to just one sand type with specific soil characteristics. An analysis of the draghead and the suction pipe, with a freely suspended visor, showed the physical processes in and around the whole suction pipe system. Because the draghead is fixed to the suction pipe, the influence of suction pipe on the draghead is analysed first. After that, the draghead is divided into two parts, the visor and the visor house. With the use of force and moment balances the trailing forces are determined for every trailing velocity. In addition, the production and its production limits are defined. The calculations show that the increase of the trailing velocity results in higher trailing forces on the suction pipe and draghead. For a velocity of around 2 m/s the draghead, for a Damen SLK600 used in the case study, will lift of from the bed. It should be notified that, among other variables, the dredging depth has an effect on this ‘floating’ point. Moreover, the results showed that the drag forces at common trailing velocities of 1-2 m/s are relatively low compared to the soil excavation forces and therefore have a small share in the total trailing forces. When the suction pipe system is trailed against the current the dragforce becomes more significant. The interaction of the draghead with the bed causes several processes to take place. The resulting relevant trailing forces are mapped and determined. The settlement of the draghead causes a hump of sand to be pushed forwards which result in a sled force and a friction force. Besides that, the flow through the pipes will cause impulse forces in the bends and at the end of the jet pipe out of the nozzle. The jets fluidize the sand which results in the largest production contribution. Furthermore, it can be seen that the penetration depth and cavity width of the jets depend on the trailing velocity and determine the amount of sand that is loosened. The cavities can overlap at low trailing velocities, resulting in a jet production limit. The jets have a significant influence on the behaviour of the visor. The freely suspended visor will drop until a solid bed layer is reached. The cutting force and vacuum force are the dominant forces working on the visor. Application of the equilibrium-moment method… Advisors/Committee Members: Miedema, Sape (mentor), van Rhee, Cees (mentor), de Koning Gans, Henk (mentor), Delft University of Technology (degree granting institution).

Subjects/Keywords: Draghead; suction pipe; freely suspended visor; trailing velocity; trailing force; drag force; jet production; penetration depth; cavity width; cutting forces; cutting layer thickness; cutting production; production mixture density

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APA (6^th Edition):

ter Meulen, G. (. (2018). Draghead Analysis: An analysis of the draghead's physical processes to determine the trailing forces and the production. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:f9d91312-4748-4218-a616-273d332aa943

Chicago Manual of Style (16^th Edition):

ter Meulen, Gijs (author). “Draghead Analysis: An analysis of the draghead's physical processes to determine the trailing forces and the production.” 2018. Masters Thesis, Delft University of Technology. Accessed January 24, 2021. http://resolver.tudelft.nl/uuid:f9d91312-4748-4218-a616-273d332aa943.

MLA Handbook (7^th Edition):

ter Meulen, Gijs (author). “Draghead Analysis: An analysis of the draghead's physical processes to determine the trailing forces and the production.” 2018. Web. 24 Jan 2021.

Vancouver:

ter Meulen G(. Draghead Analysis: An analysis of the draghead's physical processes to determine the trailing forces and the production. [Internet] [Masters thesis]. Delft University of Technology; 2018. [cited 2021 Jan 24]. Available from: http://resolver.tudelft.nl/uuid:f9d91312-4748-4218-a616-273d332aa943.

Council of Science Editors:

ter Meulen G(. Draghead Analysis: An analysis of the draghead's physical processes to determine the trailing forces and the production. [Masters Thesis]. Delft University of Technology; 2018. Available from: http://resolver.tudelft.nl/uuid:f9d91312-4748-4218-a616-273d332aa943

24. Ahonguio, Fiacre. Ecoulements de fluides à seuil autour d'obstacles : Flows of yield stress fluid around obstacles.

Degree: Docteur es, Mécanique des fluides, procédés, énergétique, 2015, Université Grenoble Alpes (ComUE)

URL: http://www.theses.fr/2015GREAI086

►

De nombreuses applications industrielles mettent en jeu des fluides complexes qui possèdent souvent un seuil d'écoulement leur permettant de résister à des efforts finis sans… (more)

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De nombreuses applications industrielles mettent en jeu des fluides complexes qui possèdent souvent un seuil d'écoulement leur permettant de résister à des efforts finis sans s'écouler. Par ailleurs, ces fluides peuvent glisser aux parois lorsque les conditions interfaciales sont favorables. Toutes ces propriétés influencent leurs écoulements autour d'obstacles. Cette thèse se propose de comprendre ces écoulements dans le domaine où les vitesses d'écoulement sont telles que les effets inertiels peuvent être négligés devant les effets visqueux eux-mêmes faibles par rapport aux effets plastiques. Elle analyse l'influence de la vitesse et du glissement sur la force de traînée et les champs cinématiques générés par l'écoulement très lent et en régime permanent d'un fluide à seuil autour d'obstacles aux surfaces adhérentes ou glissantes. Les géométries considérées sont le disque, la sphère, le cône et la plaque plane. Le fluide utilisé a un comportement élasto-viscoplastique pouvant être décrit par les modèles de Herschel-Bulkley et de Hooke. Ce comportement a été caractérisé en volume et en présence de glissement par des mesures rhéométriques. Le nombre adimensionnel clé de l'étude est le nombre d'Oldroyd, ratio entre les effets plastiques et les effets visqueux, compris ici entre 10 et 200. Les mesures de forces de traînée ont montré qu'indépendamment de l'obstacle et des conditions interfaciales, le coefficient de traînée diminue avec le nombre d'Oldroyd et tend vers une valeur asymptotique. Cette valeur montre qu'au-delà d'un certain nombre d'Oldroyd, ce coefficient n'est plus gouverné par la vitesse mais dépend uniquement du seuil et de la surface caractéristique de l'obstacle. Elle permet de calculer un critère de stabilité pour lequel l'objet est maintenu en suspension. Les champs cinématiques déterminés par PIV ont permis de caractériser la forme et l'étendue des zones rigides et cisaillées. Les mesures de forces de traînée et de champs cinématiques ont permis de quantifier la contribution des contraintes normales et tangentielles dans la force de traînée totale. La présence de glissement aux parois de l'obstacle diminue significativement le coefficient de traînée et modifie la morphologie de l'écoulement en réduisant l'étendue des zones cisaillées. Une simulation numérique a été menée dans le cas de la plaque plane avec un modèle élasto-viscoplastique et un code à éléments finis avec points d'intégration Lagrangiens.

Many industrial processes include numerous complex fluids often presenting a yield stress. Those fluids can also slip when interfacial conditions are favorable. All these properties affect their flows around obstacles. This thesis aims to understand such flows in a domain where the flow velocities are so low that inertia effects can be neglected compared to viscous effects which are substantially low compared to plastic effects. It analyzes the influence of the velocity and the slip on the drag force and the kinematic fields of the creeping flow of a yield stress fluid around obstacles either with…

Advisors/Committee Members: Jossic, Laurent (thesis director).

Subjects/Keywords: Fluide à seuil; Elasto-viscoplasticité; Glissement; Force de traînée; Stabilité; Champ de vitesse; Yield stress fluid; Elasto-viscoplasticity; Slip; Drag force; Stability; Velocity field; 620

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ahonguio, F. (2015). Ecoulements de fluides à seuil autour d'obstacles : Flows of yield stress fluid around obstacles. (Doctoral Dissertation). Université Grenoble Alpes (ComUE). Retrieved from http://www.theses.fr/2015GREAI086

Chicago Manual of Style (16^th Edition):

Ahonguio, Fiacre. “Ecoulements de fluides à seuil autour d'obstacles : Flows of yield stress fluid around obstacles.” 2015. Doctoral Dissertation, Université Grenoble Alpes (ComUE). Accessed January 24, 2021. http://www.theses.fr/2015GREAI086.

MLA Handbook (7^th Edition):

Ahonguio, Fiacre. “Ecoulements de fluides à seuil autour d'obstacles : Flows of yield stress fluid around obstacles.” 2015. Web. 24 Jan 2021.

Vancouver:

Ahonguio F. Ecoulements de fluides à seuil autour d'obstacles : Flows of yield stress fluid around obstacles. [Internet] [Doctoral dissertation]. Université Grenoble Alpes (ComUE); 2015. [cited 2021 Jan 24]. Available from: http://www.theses.fr/2015GREAI086.

Council of Science Editors:

Ahonguio F. Ecoulements de fluides à seuil autour d'obstacles : Flows of yield stress fluid around obstacles. [Doctoral Dissertation]. Université Grenoble Alpes (ComUE); 2015. Available from: http://www.theses.fr/2015GREAI086

25. CHEN HAOLIANG. Numerical study of solitary wave propagating through vegetation.

Degree: 2010, National University of Singapore

URL: http://scholarbank.nus.edu.sg/handle/10635/19029

Subjects/Keywords: vegetation; solitary wave; runup; numerical modeling; drag force coefficient; inertial force coefficient

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

HAOLIANG, C. (2010). Numerical study of solitary wave propagating through vegetation. (Thesis). National University of Singapore. Retrieved from http://scholarbank.nus.edu.sg/handle/10635/19029

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

HAOLIANG, CHEN. “Numerical study of solitary wave propagating through vegetation.” 2010. Thesis, National University of Singapore. Accessed January 24, 2021. http://scholarbank.nus.edu.sg/handle/10635/19029.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

HAOLIANG, CHEN. “Numerical study of solitary wave propagating through vegetation.” 2010. Web. 24 Jan 2021.

Vancouver:

HAOLIANG C. Numerical study of solitary wave propagating through vegetation. [Internet] [Thesis]. National University of Singapore; 2010. [cited 2021 Jan 24]. Available from: http://scholarbank.nus.edu.sg/handle/10635/19029.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

HAOLIANG C. Numerical study of solitary wave propagating through vegetation. [Thesis]. National University of Singapore; 2010. Available from: http://scholarbank.nus.edu.sg/handle/10635/19029

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

RMIT University

26. Li, C. Numerical study of isothermal gas-liquid two-phase bubbly flow.

Degree: 2011, RMIT University

URL: http://researchbank.rmit.edu.au/view/rmit:160182

► With the development of computer capability and advancement of modelling software, the technology of computational fluid dynamics (CFD) has been gradually recognized and utilized in… (more)

Subjects/Keywords: Fields of Research; Two-phase flow; population balance model; interfacial drag force; horizontal bubbly flow; Direct Quadrature Methods of Moments (DQMOM) model

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APA (6^th Edition):

Li, C. (2011). Numerical study of isothermal gas-liquid two-phase bubbly flow. (Thesis). RMIT University. Retrieved from http://researchbank.rmit.edu.au/view/rmit:160182

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Li, C. “Numerical study of isothermal gas-liquid two-phase bubbly flow.” 2011. Thesis, RMIT University. Accessed January 24, 2021. http://researchbank.rmit.edu.au/view/rmit:160182.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Li, C. “Numerical study of isothermal gas-liquid two-phase bubbly flow.” 2011. Web. 24 Jan 2021.

Vancouver:

Li C. Numerical study of isothermal gas-liquid two-phase bubbly flow. [Internet] [Thesis]. RMIT University; 2011. [cited 2021 Jan 24]. Available from: http://researchbank.rmit.edu.au/view/rmit:160182.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Li C. Numerical study of isothermal gas-liquid two-phase bubbly flow. [Thesis]. RMIT University; 2011. Available from: http://researchbank.rmit.edu.au/view/rmit:160182

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universiteit Utrecht

27. Land, V. Computing the complex : Dusty plasmas in the presence of magnetic fields and UV radiation.

Degree: 2007, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/25014

► About 90% of the visible universe is plasma. Interstellar clouds, stellar cores and atmospheres, the Solar wind, the Earth's ionosphere, polar lights, and lightning are… (more)

▼ About 90% of the visible universe is plasma. Interstellar clouds, stellar cores and atmospheres, the Solar wind, the Earth's ionosphere, polar lights, and lightning are all plasma; ionized gases, consisting of electrons, ions, and neutrals. Not only many industries, like the microchip and solar cell industry, but also future fusion power stations, rely heavily on the use of plasma. More and more, home appliances include plasma technologies, like compact fluorescent light sources, and plasma screens. Dust particles, which can disrupt plasma processes, enter these plasmas, through chemical reactions in the plasma, or through interactions between plasma and walls. For instance, during microchip fabrication, dust particles can destroy the tiny, nanometre-sized structures on the surface of these chips. On the other hand, dust particles orbiting Young Stellar Objects coagulate and form the seeds of planets. In order to understand fundamental processes, such as planet formation, or to optimize industrial plasma processes, a thorough description of dusty plasma is necessary. Dust particles immersed in plasma collect ions and electrons from the plasma and charge up electrically. Therefore, the presence of dust changes plasma, while at the same time many forces start acting on the dust. Therefore, the dust and plasma become coupled, making dusty plasma a very complex medium to describe, in which many length and time scales play a role, from the Debye length to the length of the electrodes, and from the inverse plasma frequencies to the dust transport times. Using a self-consistent fluid model, we simulate these multi-scale dusty plasmas in radio frequency discharges under micro-gravity. We show that moderate non-linear scattering of ions by the dust particles is the most important aspect in the calculation of the ion drag force. This force is also responsible for the formation of a dust-free 'void' in dusty plasma under micro-gravity, caused by ions moving from the centre of the void towards the outside of the discharge. The void thus requires electron-impact ionizations inside the void. The electrons gain the energy for these ionizations inside the dust cloud surrounding the void, however. We show that a growing electron temperature gradient is responsible for the transport of electron energy from the surrounding dust cloud into the void. An axial magnetic field in the discharge magnetizes the electrons. This changes the ambipolar flux of ions through the bulk of the discharge. The ion drag force changes, resulting in a differently shaped void and faster void formation. Experiments in a direct current discharge, show a response of both dust and plasma in the E?B direction, when a magnetic field is applied. The dust response consists of two phases: an initial fast phase, and a later, slow phase. Using a Particle-In-Cell plus Monte Carlo model, we show that the dust charge can be reduced by adding a flux of ultraviolet radiation. A source of ultraviolet light can thus serve as a tool to manipulate dusty plasmas, but might also…

Subjects/Keywords: Natuur- en Sterrenkunde; complex plasma; dust charging; dusty plasma; ion drag force; magnetic fields; micro-gravity; multi-scale physics; radio frequency discharge; simulation; ultraviolet radiation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Land, V. (2007). Computing the complex : Dusty plasmas in the presence of magnetic fields and UV radiation. (Doctoral Dissertation). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/25014

Chicago Manual of Style (16^th Edition):

Land, V. “Computing the complex : Dusty plasmas in the presence of magnetic fields and UV radiation.” 2007. Doctoral Dissertation, Universiteit Utrecht. Accessed January 24, 2021. http://dspace.library.uu.nl:8080/handle/1874/25014.

MLA Handbook (7^th Edition):

Land, V. “Computing the complex : Dusty plasmas in the presence of magnetic fields and UV radiation.” 2007. Web. 24 Jan 2021.

Vancouver:

Land V. Computing the complex : Dusty plasmas in the presence of magnetic fields and UV radiation. [Internet] [Doctoral dissertation]. Universiteit Utrecht; 2007. [cited 2021 Jan 24]. Available from: http://dspace.library.uu.nl:8080/handle/1874/25014.

Council of Science Editors:

Land V. Computing the complex : Dusty plasmas in the presence of magnetic fields and UV radiation. [Doctoral Dissertation]. Universiteit Utrecht; 2007. Available from: http://dspace.library.uu.nl:8080/handle/1874/25014

28. Andrea Inés Borgazzi. Dynamics of coronal mass ejections in the interplanetary medium.

Degree: 2009, Instituto Nacional de Pesquisas Espaciais

URL: http://urlib.net/sid.inpe.br/[email protected]/2009/07.17.18.13

►

Neste trabalho nós apresentamos uma descrição acurada da dinâmica das ejeções coronais de massa interplanetárias (ICMEs) em sua viagem do Sol à Terra. Nós propomos… (more)

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Neste trabalho nós apresentamos uma descrição acurada da dinâmica das ejeções coronais de massa interplanetárias (ICMEs) em sua viagem do Sol à Terra. Nós propomos um mecanismo de transferência de momento entre as ICMEs e o vento solar que a circunda que desacelera as ICMEs rápidas (V_cme >V_sw). Neste caso, a desaceleração envolve a ação de forças entre a ICME e o meio que a circunda. Nós resolvemos as equações diferenciais que descrevem o processo e usamos diferentes expressões para a força viscosa, de acordo com o número de Reynolds. Nós encontramos soluções que incluem a variabilidades do raio da ICME bem como a da densidade de massa do meio interplanetário. Nós encontramos o comportamento da velocidade da ICME versus a distância percorrida e apresentamos as soluções analíticas com a correpondente análise de dados remotos e in situ. Nós discutimos as implicações dos diferentes parâmetros envolvidos neste processo de transferência de momento. Nós consideramos a massa da ICME, (m_cme), a densidade do meio interplanetário, a velocidade do vento solar, (V_sw), o expoente da expansão radial das ICMEs, (p), o coeficiente de arrasto, (C_d), e o coeficiente da viscosidade cinética, (v).

In this work we present an accurate description of the lnterplanetary Coronal Mass Ejections (ICMEs) dynamics in their travel from Sun to Earth. We propose a mechanism of momentum transfer between ICMEs and the surrounding solar wind that decelerate the fast ICMEs (V_cme >V_sw). In this case, the deceleration involves viscous forces acting between the ICME and the surrounding medium. We solve the differential equations that describe the process using differcnt expressions for the viscous force. We find solutions that include the variability of the ICME radio and the mass density of the medium and find out the speed behavior of the ICMEs versus the traveled distance. We present the analytical solutions with the corresponding in situ and remote data analysis and discuss the implications of the different parameters involved in this mechanism of momentum transfer. We consider the ICME mass, (m_cme), the density ofthe interplanetary medium, the solar wind speed, (V_sw), the exponent of radial expansion of the ICME, (p), the drag coefficient, (C_d), and kinematic viscous coefficient, (v).

Advisors/Committee Members: Alisson Dal Lago, Ezequiel Echer, Maria Virgínia Alves, Alejandro Lara Sanchez, Luiz Fernando Ziebell, Vera Jatenco Silva Pereira, José Ricardo Abalde Guede.

Subjects/Keywords: ICME; transport in the interplanetary medium; drag force; travel time; transporte no meio interplanetário; força de arrasto; tempo de viagem; viscosidade; viscosty; ICME

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Borgazzi, A. I. (2009). Dynamics of coronal mass ejections in the interplanetary medium. (Thesis). Instituto Nacional de Pesquisas Espaciais. Retrieved from http://urlib.net/sid.inpe.br/[email protected]/2009/07.17.18.13

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Borgazzi, Andrea Inés. “Dynamics of coronal mass ejections in the interplanetary medium.” 2009. Thesis, Instituto Nacional de Pesquisas Espaciais. Accessed January 24, 2021. http://urlib.net/sid.inpe.br/[email protected]/2009/07.17.18.13.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Borgazzi, Andrea Inés. “Dynamics of coronal mass ejections in the interplanetary medium.” 2009. Web. 24 Jan 2021.

Vancouver:

Borgazzi AI. Dynamics of coronal mass ejections in the interplanetary medium. [Internet] [Thesis]. Instituto Nacional de Pesquisas Espaciais; 2009. [cited 2021 Jan 24]. Available from: http://urlib.net/sid.inpe.br/[email protected]/2009/07.17.18.13.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Borgazzi AI. Dynamics of coronal mass ejections in the interplanetary medium. [Thesis]. Instituto Nacional de Pesquisas Espaciais; 2009. Available from: http://urlib.net/sid.inpe.br/[email protected]/2009/07.17.18.13

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

29. Khamis, Eduardo Georges. Formação de sólitons em condensados de Bose-Einstein e em meios ópticos.

Degree: PhD, Física, 2010, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/43/43134/tde-20122010-160534/ ;

►

Diferentes tipos de sólitons têm sido observados em meios ópticos não-lineares, e seus comportamentos individuais descritos pela equação não-linear de Schrödinger e pela equação não-linear… (more)

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Diferentes tipos de sólitons têm sido observados em meios ópticos não-lineares, e seus comportamentos individuais descritos pela equação não-linear de Schrödinger e pela equação não-linear de Schrödinger generalizada, em diferentes dimensões e geometrias. Entretando, há situações onde muitos sólitons são gerados formando uma densa rede de sólitons. Nestes casos, é impossível desprezar as interações entre os sólitons e temos que considerar a evolução da estrutura como um todo. A teoria das ondas de choque dispersivas em meios fotorrefrativos e a teoria da difração não-linear de intensos feixes de luz propagando-se em meios fotorrefrativos com um fio refletor incorporado a esse meio foi desenvolvida, e verificamos que está em excelente acordo com nossas simulações numéricas. No caso da formação de sólitons em condensados, fizemos cálculos numéricos realísticos dentro da aproximação de campo médio usando a equação de Gross-Pitaevskii, incluindo também um potencial de confinamento, um potencial móvel e um potencial dipolar. A maioria dos resultados puderam ser comparados com experimentos recentes.

Different kinds of solitons have already been observed in various nonlinear optical media, and their behavior has been explained in the frameworks of such mathematical models as the nonlinear Schrödinger and generalized nonlinear Shrödinger equations for different dimensions and geometries. However, there are situations when many solitons are generated so that they can comprise a dense soliton train. In such situations, it is impossible to neglect interactions between solitons and one has to consider the evolution of the structure as a whole rather than to trace the evolution of each soliton separately. The theory of optical shock waves in photorefractive media and the theory of nonlinear diffraction of light beams propagating in photorefractive media with embedded reflecting wire was developed and agrees very well with our numerical simulations. In the condensate soliton formation case, we did numerical calculations in the mean field approach using the Gross-Pitaevskii equation, adding a trap potential and a moving potential and a potential of the dipole-dipole interaction. The main results were also checked by recent experiments.

Advisors/Committee Members: Gammal, Arnaldo.

Subjects/Keywords: Bose-Einstein condensation; condensação de Bose-Einstein; condensados dipolares; dipolar condensates; drag force; força de arrasto; meios fotorrefrativos; ondas de choque; photorefractive media; shock waves; solitons; sólitons

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Khamis, E. G. (2010). Formação de sólitons em condensados de Bose-Einstein e em meios ópticos. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/43/43134/tde-20122010-160534/ ;

Chicago Manual of Style (16^th Edition):

Khamis, Eduardo Georges. “Formação de sólitons em condensados de Bose-Einstein e em meios ópticos.” 2010. Doctoral Dissertation, University of São Paulo. Accessed January 24, 2021. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-20122010-160534/ ;.

MLA Handbook (7^th Edition):

Khamis, Eduardo Georges. “Formação de sólitons em condensados de Bose-Einstein e em meios ópticos.” 2010. Web. 24 Jan 2021.

Vancouver:

Khamis EG. Formação de sólitons em condensados de Bose-Einstein e em meios ópticos. [Internet] [Doctoral dissertation]. University of São Paulo; 2010. [cited 2021 Jan 24]. Available from: http://www.teses.usp.br/teses/disponiveis/43/43134/tde-20122010-160534/ ;.

Council of Science Editors:

Khamis EG. Formação de sólitons em condensados de Bose-Einstein e em meios ópticos. [Doctoral Dissertation]. University of São Paulo; 2010. Available from: http://www.teses.usp.br/teses/disponiveis/43/43134/tde-20122010-160534/ ;

University of Michigan

30. Wang, Nianqing. Equations and properties of flows with drifting and oscillating bubbles.

Degree: PhD, Pure Sciences, 1999, University of Michigan

URL: http://hdl.handle.net/2027.42/132272

► We study liquid flows with many small spherical gas bubbles. Heat transfer, surface tension and gas mass are neglected. Viscosity and gravity are added in… (more)

Subjects/Keywords: Bubbly Flow; Drag Force; Drifting; Equations; Flows; Oscillating Bubbles; Properties

Record Details Similar Records Cite « Share

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wang, N. (1999). Equations and properties of flows with drifting and oscillating bubbles. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/132272

Chicago Manual of Style (16^th Edition):

Wang, Nianqing. “Equations and properties of flows with drifting and oscillating bubbles.” 1999. Doctoral Dissertation, University of Michigan. Accessed January 24, 2021. http://hdl.handle.net/2027.42/132272.

MLA Handbook (7^th Edition):

Wang, Nianqing. “Equations and properties of flows with drifting and oscillating bubbles.” 1999. Web. 24 Jan 2021.

Vancouver:

Wang N. Equations and properties of flows with drifting and oscillating bubbles. [Internet] [Doctoral dissertation]. University of Michigan; 1999. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/2027.42/132272.

Council of Science Editors:

Wang N. Equations and properties of flows with drifting and oscillating bubbles. [Doctoral Dissertation]. University of Michigan; 1999. Available from: http://hdl.handle.net/2027.42/132272

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