subject:(Suspension flow)

Delft University of Technology

1. Zaat, Loulou (author). Below the surface: A laboratorial research to the vertical distribution of buoyant plastics in rivers.

Degree: 2020, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:1b40f6c9-7532-4033-9e13-d5efb927f9ac

► Rivers are identified as main sources of plastic litter in oceans. About 65% of the plastic litter is buoyant in fresh waters, meaning it has… (more)

▼ Rivers are identified as main sources of plastic litter in oceans. About 65% of the plastic litter is buoyant in fresh waters, meaning it has the capability to float, making transport over rivers relatively easy. A better understanding of how plastic litter is transported via rivers is crucial. Both for quantification and mitigation of the plastic problem. Most research on quantification of the plastic flux is based on surface-measurements only, up till about 50 cm water-depth. Thereby, most cleaning strategies focus on skimming only the surface. This research investigates the distribution of buoyant plastic litter over the water depth in rivers. Given the wide use of marginal buoyant plastics, it is hypothesized that a significant share of the plastic in rivers is transported below the first 50 cm surface-water, due to the mixing ability of turbulent flow. In such case, a great share of the plastic litter is overlooked in both flux estimates and riverine removal strategies. The question arises: How is plastic distributed over the water depth in rivers and how is this distribution related to prevailing flow conditions? The research is based on four pillars: Knowledge on the hydraulic plastic parameters (1), in combination with experimental observations (2), might lead to an explanation of the distribution with a theoretical approximation (3), based on existing literature from neighboring research fields. Lastly, manipulation (4) of this plastic distribution by hydraulic interventions is investigated. With this research, a first insight is created on the vertical behavior of plastic in relation to the flow conditions. This study shows that marginal buoyant plastics can be sensitive to turbulent motions in flow and a significant amount of plastic might be transported below the surface. In order to create a complete picture of the behavior of different kinds of plastic in stream flows, more extensive research is needed. Advisors/Committee Members: Bogaard, Thom (mentor), Hoes, Olivier (graduation committee), Uijttewaal, Wim (graduation committee), van Emmerik, Tim (graduation committee), Delft University of Technology (degree granting institution).

Subjects/Keywords: plastic; buoyant; floating; suspension; rivers; turbulent flow

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APA (6^th Edition):

Zaat, L. (. (2020). Below the surface: A laboratorial research to the vertical distribution of buoyant plastics in rivers. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:1b40f6c9-7532-4033-9e13-d5efb927f9ac

Chicago Manual of Style (16^th Edition):

Zaat, Loulou (author). “Below the surface: A laboratorial research to the vertical distribution of buoyant plastics in rivers.” 2020. Masters Thesis, Delft University of Technology. Accessed April 12, 2021. http://resolver.tudelft.nl/uuid:1b40f6c9-7532-4033-9e13-d5efb927f9ac.

MLA Handbook (7^th Edition):

Zaat, Loulou (author). “Below the surface: A laboratorial research to the vertical distribution of buoyant plastics in rivers.” 2020. Web. 12 Apr 2021.

Vancouver:

Zaat L(. Below the surface: A laboratorial research to the vertical distribution of buoyant plastics in rivers. [Internet] [Masters thesis]. Delft University of Technology; 2020. [cited 2021 Apr 12]. Available from: http://resolver.tudelft.nl/uuid:1b40f6c9-7532-4033-9e13-d5efb927f9ac.

Council of Science Editors:

Zaat L(. Below the surface: A laboratorial research to the vertical distribution of buoyant plastics in rivers. [Masters Thesis]. Delft University of Technology; 2020. Available from: http://resolver.tudelft.nl/uuid:1b40f6c9-7532-4033-9e13-d5efb927f9ac

2. Roht, Yanina Lucrecia. Transport et dispersion d’un traceur dans un écoulement de suspensions oscillant : Transporte y dispersión de un soluto en un flujo de suspensiones.

Degree: Docteur es, Mécanique des fluides, 2017, Université Paris-Saclay (ComUE); Universidad de Buenos Aires. Facultad de Ingeniería

URL: http://www.theses.fr/2017SACLS065

► On étudie le transport et la dispersion hydrodynamique d’un traceur passif et/ou d’une suspension de particules dans deux fractures modèles avec deux parois lisses ou… (more)

▼ On étudie le transport et la dispersion hydrodynamique d’un traceur passif et/ou d’une suspension de particules dans deux fractures modèles avec deux parois lisses ou avec une distribution aléatoire d’obstacles dans l’ouverture. On utilise un écoulement oscillant d’un fluide newtonien afin d’observer les effets sur la dispersion de la réversibilité du déplacement. On caractérise de manière quantitative l’influence des paramètres caractéristiques de l’écoulement: période T et amplitude A des oscillations et temps caractéristique τ_m de diffusion moléculaire sur l’épaisseur.Dans le cas de parois lisses, on montre que les régimes de dispersion sont déterminés par le rapport τ_m/T . Pour τ_m/T≤2, le régime de dispersion de Taylor est dominant et irréversible à l’échelle globale. Pour τ_m/T≥20, on a un régime partiellement réversible pour lequel le mélange reste diffusif à l’échelle globale mais où, localement, la distribution des particules de traceur dans l’épaisseur suit les oscillations de la vitesse locale v_x (z,t) . Dans ce cas, il existe une composante purement convective et réversible de la dispersion.Dans le cas d’une cellule rugueuse, le désordre induit par les obstacles fait apparaitre une composante de dispersion géométrique quand τ_m/T≤0,6, pour laquelle la dispersivité normalisée par l’amplitude l_d/A ne dépend pas de la période T. On observe le régime de dispersion de Taylor dans une gamme 〖0,8≤τ〗_m/T≤1 dépendant de l’amplitude de l’oscillation. Lorsque τ_m/T≥20, on observe le régime de dispersion partiellement réversible déjà observé précédemment dans la cellule lisse. En comparant ces mesures avec celles obtenues par des techniques complémentaires (écho et transmission), on a pu séparer la composante irréversible de la dispersion de la composante réversible associée à des chenaux macroscopiques d’écoulement préférentiel dus à la géométrie de la fracture. L’influence sur la dispersion de particules de 40 µm de diamètre en suspension dans l’écoulement oscillant a été ensuite étudiée dans la cellule lisse. La mesure globale de dispersion a mis en évidence les mêmes régimes d’écoulement qu’en l’absence de particules avec des domaines d’existence déterminés, comme dans ce cas, par la valeur du rapport τ_m/T.Pour mieux comprendre l’origine microscopique des résultats, nous avons suivi les trajectoires individuelles des particules dans un écoulement oscillant. Leur mouvement et la distribution de leurs vitesses ont été mesurés dans plusieurs couches à différentes distances dans l’épaisseur. On observe que les particules suivent les lignes de courant et que le profil de leurs vitesses dans l’épaisseur a la forme parabolique d’un profil de Poiseuille. Par ailleurs, nous avons comparé les distributions des particules après un certain nombre d’oscillations à celles au temps initial et observé, pour de longues périodes T, une migration des particules vers les parois de la cellule. Enfin, certaines particules présentant une réversibilité cinématique de leur mouvement, avec des allers retours suivant la même… Advisors/Committee Members: Auradou, Harold (thesis director), Ippolito, Irene (thesis director), Chertcoff, Ricardo (thesis director).

Subjects/Keywords: Dispersion; Écoulement oscillant; Suspension; Particules; Dispersion; Oscillating flow; Suspension; Particles; Dispersión; Flujo oscilante; Suspensión; Partículas

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

APA (6^th Edition):

Roht, Y. L. (2017). Transport et dispersion d’un traceur dans un écoulement de suspensions oscillant : Transporte y dispersión de un soluto en un flujo de suspensiones. (Doctoral Dissertation). Université Paris-Saclay (ComUE); Universidad de Buenos Aires. Facultad de Ingeniería. Retrieved from http://www.theses.fr/2017SACLS065

Chicago Manual of Style (16^th Edition):

Roht, Yanina Lucrecia. “Transport et dispersion d’un traceur dans un écoulement de suspensions oscillant : Transporte y dispersión de un soluto en un flujo de suspensiones.” 2017. Doctoral Dissertation, Université Paris-Saclay (ComUE); Universidad de Buenos Aires. Facultad de Ingeniería. Accessed April 12, 2021. http://www.theses.fr/2017SACLS065.

MLA Handbook (7^th Edition):

Roht, Yanina Lucrecia. “Transport et dispersion d’un traceur dans un écoulement de suspensions oscillant : Transporte y dispersión de un soluto en un flujo de suspensiones.” 2017. Web. 12 Apr 2021.

Vancouver:

Roht YL. Transport et dispersion d’un traceur dans un écoulement de suspensions oscillant : Transporte y dispersión de un soluto en un flujo de suspensiones. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); Universidad de Buenos Aires. Facultad de Ingeniería; 2017. [cited 2021 Apr 12]. Available from: http://www.theses.fr/2017SACLS065.

Council of Science Editors:

Roht YL. Transport et dispersion d’un traceur dans un écoulement de suspensions oscillant : Transporte y dispersión de un soluto en un flujo de suspensiones. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); Universidad de Buenos Aires. Facultad de Ingeniería; 2017. Available from: http://www.theses.fr/2017SACLS065

University of Edinburgh

3. Ness, Christopher John. Suspension rheology and extrusion : a discrete element method study.

Degree: PhD, 2016, University of Edinburgh

URL: http://hdl.handle.net/1842/20392

► A suspension is a fully saturated mixture of discrete solid particles and interstitial liquid. Examples of suspensions include pastes, slurries, cement, food-spreads, drilling fluids and… (more)

▼ A suspension is a fully saturated mixture of discrete solid particles and interstitial liquid. Examples of suspensions include pastes, slurries, cement, food-spreads, drilling fluids and some geophysical flows. The present work focusses on granular (as opposed to colloidal) suspensions, which we define as those for which the thermal motion of the solid particles is negligible. Despite such ubiquity in industry and nature, our understanding of the mechanical properties of suspensions lags behind that of their constituent solid and liquids. In this thesis, the discrete element method is used to simulate suspension flow in shear, capillary and constriction geometries, mapping and characterising the fundamental flow, or rheological, regimes. As a starting point (Chapter 2), we consider an established regime map for dry granular materials, appropriate for flows of sand, grains and dry debris. Taking guidance from shear flow simulations that consider the lubricating effect of an interstitial liquid, we recast the regime map for a general suspension, elucidating flows comparable to the dry material or to a viscous liquid, dependent on the shear rate, liquid viscosity and particle stiffness. We give an account of the microstructural traits associated with each regime. Motivated by recent groundbreaking theoretical, computational and experimental work, we incorporate the emerging picture of frictional shear thickening into our regime map (Chapter 3). Our shear flow simulations capture the shear thickening behaviour and demonstrate that it may, in principle, occur in any of the identified flow regimes. Our simulations of time-dependent shear flows (Chapter 4), specifically flow reversal, provide a detailed micro-mechanical explanation of a longstanding and previously unexplained experimental finding, guiding future experimentalists in decomposing the particle and liquid contributions to the viscosity of any suspension. Indeed, the findings have already been exploited in the devising of an experimental protocol that has successfully proven the dominance of particle contacts in driving shear thickening. We next consider suspension flow in a microchannel (Chapter 5), finding that the identified shear flow regimes are locally applicable to flows in complex geometries under inhomogeneous stress conditions only when the local mean shear rate exceeds temporal velocity fluctuations. A more comprehensive description is therefore required to fully characterise the flow behaviour in this geometry. Finally (Chapter 6), we simulate pressure driven suspension flow through a constriction geometry, observing highly inhomogeneous stress distributions and velocity profiles. The roles of particle and fluid properties are considered in the context of an industrial paste extrusion process.

Subjects/Keywords: 531; suspension; granular suspension; rheology; flow; frictional shear thickening; shear rate; constriction geometry

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APA (6^th Edition):

Ness, C. J. (2016). Suspension rheology and extrusion : a discrete element method study. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/20392

Chicago Manual of Style (16^th Edition):

Ness, Christopher John. “Suspension rheology and extrusion : a discrete element method study.” 2016. Doctoral Dissertation, University of Edinburgh. Accessed April 12, 2021. http://hdl.handle.net/1842/20392.

MLA Handbook (7^th Edition):

Ness, Christopher John. “Suspension rheology and extrusion : a discrete element method study.” 2016. Web. 12 Apr 2021.

Vancouver:

Ness CJ. Suspension rheology and extrusion : a discrete element method study. [Internet] [Doctoral dissertation]. University of Edinburgh; 2016. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/1842/20392.

Council of Science Editors:

Ness CJ. Suspension rheology and extrusion : a discrete element method study. [Doctoral Dissertation]. University of Edinburgh; 2016. Available from: http://hdl.handle.net/1842/20392

4. Debba, Djihad. Etude locale des mécanismes de réentrainement des microparticules en conduite ventilée : Local experimental study of microparticles resuspension mechanisms in ventilated duct under accelerated flow.

Degree: Docteur es, Mécanique des milieux fluides, 2017, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire

URL: http://www.theses.fr/2017IMTA0059

►

L’objectif de cette étude est de bien décrire les mécanismes impliqués dans la remise en suspension des microparticules en conduite ventilée. Une méthodologie expérimentale est… (more)

▼

L’objectif de cette étude est de bien décrire les mécanismes impliqués dans la remise en suspension des microparticules en conduite ventilée. Une méthodologie expérimentale est utilisée, et cela en tenant compte de la période d’accélération de l’écoulement qui précède l’atteinte du régime permanent. Une méthode optique a été choisi pour étudier le mouvement initial des particules, et leur cinétique de remise en suspension. Parallèlement, nous avons recueilli des données locales de l’écoulement en période d’accélération et au régime permanent.Le démarrage de la remise en suspension a été analysé relativement à l’évolution temporelle de trois paramètres pouvant influencer le démarrage de la remise en suspension, le premier est la vitesse instantanée en proche paroi, le second est l’intensité turbulente, et enfin le troisième est l’énergie cinétique turbulente. Le paramètre prépondérant sur le démarrage de la remise en suspension semble être l’énergie cinétique turbulente.

The objective of this study is to well describe the mechanisms involved in the resuspension of particles in ventilated duct by using an experimental methodology and taking into account the acceleration of the air flow which always precedes steady state. For that purpose, we chose an optical method in order to investigate the initial movement of particles, and to quantify the resuspension kinetics. In parallel we collected local data of the flow during acceleration and steady state.We observed that the resuspension kinetics starts during the acceleration period and extends to steady state. We highlighted the relevant velocity characteristics (critical velocity at the center duct and close to the wall, critical kinetic energy range) to explain this phenomenon. The resuspension start seems to be linked with a critical kinetic energy range.

Advisors/Committee Members: Solliec, Camille (thesis director), Le Coq, Laurence (thesis director).

Subjects/Keywords: Remise en suspension des particules; Accélération; Particle resuspension; Accelerated flow; 620

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APA (6^th Edition):

Debba, D. (2017). Etude locale des mécanismes de réentrainement des microparticules en conduite ventilée : Local experimental study of microparticles resuspension mechanisms in ventilated duct under accelerated flow. (Doctoral Dissertation). Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire. Retrieved from http://www.theses.fr/2017IMTA0059

Chicago Manual of Style (16^th Edition):

Debba, Djihad. “Etude locale des mécanismes de réentrainement des microparticules en conduite ventilée : Local experimental study of microparticles resuspension mechanisms in ventilated duct under accelerated flow.” 2017. Doctoral Dissertation, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire. Accessed April 12, 2021. http://www.theses.fr/2017IMTA0059.

MLA Handbook (7^th Edition):

Debba, Djihad. “Etude locale des mécanismes de réentrainement des microparticules en conduite ventilée : Local experimental study of microparticles resuspension mechanisms in ventilated duct under accelerated flow.” 2017. Web. 12 Apr 2021.

Vancouver:

Debba D. Etude locale des mécanismes de réentrainement des microparticules en conduite ventilée : Local experimental study of microparticles resuspension mechanisms in ventilated duct under accelerated flow. [Internet] [Doctoral dissertation]. Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire; 2017. [cited 2021 Apr 12]. Available from: http://www.theses.fr/2017IMTA0059.

Council of Science Editors:

Debba D. Etude locale des mécanismes de réentrainement des microparticules en conduite ventilée : Local experimental study of microparticles resuspension mechanisms in ventilated duct under accelerated flow. [Doctoral Dissertation]. Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire; 2017. Available from: http://www.theses.fr/2017IMTA0059

University of Guelph

5. Mistry, Rakesh. Suspension Feeding of Juvenile and Adult Freshwater Mussels (Bivalvia: Unionidae) Under Flowing Conditions.

Degree: MS, Department of Integrative Biology, 2015, University of Guelph

URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/8934

► I examined the feeding abilities of adult and juvenile freshwater unionid mussels, using two closely related species, Lampsilis siliquoidea and Lampsilis fasciola, and two other… (more)

Subjects/Keywords: Bivalve; Unionid; Suspension Feeding; Flow cytometry; Selective Feeding

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APA (6^th Edition):

Mistry, R. (2015). Suspension Feeding of Juvenile and Adult Freshwater Mussels (Bivalvia: Unionidae) Under Flowing Conditions. (Masters Thesis). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/8934

Chicago Manual of Style (16^th Edition):

Mistry, Rakesh. “Suspension Feeding of Juvenile and Adult Freshwater Mussels (Bivalvia: Unionidae) Under Flowing Conditions.” 2015. Masters Thesis, University of Guelph. Accessed April 12, 2021. https://atrium.lib.uoguelph.ca/xmlui/handle/10214/8934.

MLA Handbook (7^th Edition):

Mistry, Rakesh. “Suspension Feeding of Juvenile and Adult Freshwater Mussels (Bivalvia: Unionidae) Under Flowing Conditions.” 2015. Web. 12 Apr 2021.

Vancouver:

Mistry R. Suspension Feeding of Juvenile and Adult Freshwater Mussels (Bivalvia: Unionidae) Under Flowing Conditions. [Internet] [Masters thesis]. University of Guelph; 2015. [cited 2021 Apr 12]. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/8934.

Council of Science Editors:

Mistry R. Suspension Feeding of Juvenile and Adult Freshwater Mussels (Bivalvia: Unionidae) Under Flowing Conditions. [Masters Thesis]. University of Guelph; 2015. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/8934

Delft University of Technology

6. Fikriyan, Rafil (author). Lateral Migration of Particles Under Poiseuille Flow.

Degree: 2019, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:09aefb88-75c0-4935-8d06-1cb3fe996365

►

The phenomenon of lateral migration of neutrally buoyant rigid spheres is studied experimentally for Poiseuille Flow. The study relied on the particle migration technique to… (more)

Subjects/Keywords: multiphase flow; Suspension; Fluid Mechanics; Tubular Pinch Effect; Particle Migration

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APA (6^th Edition):

Fikriyan, R. (. (2019). Lateral Migration of Particles Under Poiseuille Flow. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:09aefb88-75c0-4935-8d06-1cb3fe996365

Chicago Manual of Style (16^th Edition):

Fikriyan, Rafil (author). “Lateral Migration of Particles Under Poiseuille Flow.” 2019. Masters Thesis, Delft University of Technology. Accessed April 12, 2021. http://resolver.tudelft.nl/uuid:09aefb88-75c0-4935-8d06-1cb3fe996365.

MLA Handbook (7^th Edition):

Fikriyan, Rafil (author). “Lateral Migration of Particles Under Poiseuille Flow.” 2019. Web. 12 Apr 2021.

Vancouver:

Fikriyan R(. Lateral Migration of Particles Under Poiseuille Flow. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Apr 12]. Available from: http://resolver.tudelft.nl/uuid:09aefb88-75c0-4935-8d06-1cb3fe996365.

Council of Science Editors:

Fikriyan R(. Lateral Migration of Particles Under Poiseuille Flow. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:09aefb88-75c0-4935-8d06-1cb3fe996365

Georgia Tech

7. Schmidt, Eric Andrew. Characterizaton of a fiber suspesion jet in a co-flow dilution process.

Degree: PhD, Institute of Paper Science and Technology, 2003, Georgia Tech

URL: http://hdl.handle.net/1853/7090

Subjects/Keywords: Suspension; Fluid flow; Jets

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

APA (6^th Edition):

Schmidt, E. A. (2003). Characterizaton of a fiber suspesion jet in a co-flow dilution process. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/7090

Chicago Manual of Style (16^th Edition):

Schmidt, Eric Andrew. “Characterizaton of a fiber suspesion jet in a co-flow dilution process.” 2003. Doctoral Dissertation, Georgia Tech. Accessed April 12, 2021. http://hdl.handle.net/1853/7090.

MLA Handbook (7^th Edition):

Schmidt, Eric Andrew. “Characterizaton of a fiber suspesion jet in a co-flow dilution process.” 2003. Web. 12 Apr 2021.

Vancouver:

Schmidt EA. Characterizaton of a fiber suspesion jet in a co-flow dilution process. [Internet] [Doctoral dissertation]. Georgia Tech; 2003. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/1853/7090.

Council of Science Editors:

Schmidt EA. Characterizaton of a fiber suspesion jet in a co-flow dilution process. [Doctoral Dissertation]. Georgia Tech; 2003. Available from: http://hdl.handle.net/1853/7090

University of Edinburgh

8. Richards, James Alexander. Friction and the flow of concentrated suspensions.

Degree: PhD, 2020, University of Edinburgh

URL: http://hdl.handle.net/1842/36913

► Suspensions are ubiquitous in industrial processing, yet fundamental understanding of how they flow remains limited. Recent progress on shear-thickening suspensions of non-Brownian particles establishes the… (more)

▼ Suspensions are ubiquitous in industrial processing, yet fundamental understanding of how they flow remains limited. Recent progress on shear-thickening suspensions of non-Brownian particles establishes the importance of direct mechanical contact and friction between particles. This represents a paradigm shift, linking wet suspensions to dry granular materials through a static jamming volume fraction. In this thesis I explore further the implications of mechanical contact in three ways. Firstly in time-dependent flows, I show that large shear-rate fluctuations arise from a competition between rapid microscopic contact dynamics and the slow dynamics controlling how the suspension is sheared. I develop a dynamical-systems approach that graphically shows how an instability arises, indicates how to control the instability, and allows the extraction of a contact relaxation time that is inaccessible to conventional rheometry. Next, more complex interparticle interactions are considered. I take the relevant effect to be a stress-dependent constraint on relative interparticle motion, e.g., sliding, twisting or rolling. Constraints lower the jamming volume fraction and can either form or break with stress. I show that an interplay between two constraint types can capture all classes of flow curve, with predictions compared against my own experimental or literature data. In particular, a yield stress behaviour is reproduced for rolling constraints being broken while sliding is constrained. Finally, I investigate the protocol dependence of yield-stress suspension rheology. The complex experimental phenomenology is shown to be consistent with an adhesively-bonded compressive frictional contact network. The yield stress is hence related to jamming and constraints, rather than just resulting from interparticle attraction. This finding continues the transition of non-Brownian suspension rheology from the colloidal to the granular frame and suggests novel ways to tune the yielding behaviour through the interparticle friction coefficient or flow protocols.

Subjects/Keywords: non-Brownian suspension; shear-induced jamming; unsteady flow; sticky particles; modelling

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APA (6^th Edition):

Richards, J. A. (2020). Friction and the flow of concentrated suspensions. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/36913

Chicago Manual of Style (16^th Edition):

Richards, James Alexander. “Friction and the flow of concentrated suspensions.” 2020. Doctoral Dissertation, University of Edinburgh. Accessed April 12, 2021. http://hdl.handle.net/1842/36913.

MLA Handbook (7^th Edition):

Richards, James Alexander. “Friction and the flow of concentrated suspensions.” 2020. Web. 12 Apr 2021.

Vancouver:

Richards JA. Friction and the flow of concentrated suspensions. [Internet] [Doctoral dissertation]. University of Edinburgh; 2020. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/1842/36913.

Council of Science Editors:

Richards JA. Friction and the flow of concentrated suspensions. [Doctoral Dissertation]. University of Edinburgh; 2020. Available from: http://hdl.handle.net/1842/36913

Virginia Tech

9. Zhu, Zebo. Flow Characterization and Redesign of Load-Leveling Valves for Improving Transient Dynamics of Heavy Truck Air Suspensions.

Degree: MS, Mechanical Engineering, 2016, Virginia Tech

URL: http://hdl.handle.net/10919/73606

► This research provides a thorough flow characterization study to compare the functionality of two types of load-leveling valves that are commonly used for air suspension… (more)

▼ This research provides a thorough flow characterization study to compare the functionality of two types of load-leveling valves that are commonly used for air suspension systems of commercial trucks. The first valve features a simple disk/slot design and is relatively compact for installation. The second type is larger and has a sophisticated, chambered design, which allows for considerably quicker fill and exhaust response times in the transient region. A new approach is introduced to estimate the transient mass flow rate of a load-leveling valve under different suspension pressures, without requiring a mass flow meter. An extensive series of dynamic tests are conducted to characterize and compare the two load-leveling valves. A generic heavy-truck pneumatic suspension, consisting of load-leveling valves, airspring, air tank, and air-hose fittings, is configured for testing. The test setup is used to evaluate the transient performance of each type of load-leveling valve in a typical truck suspension. The flow behavior of the system is validated by the force/pressure responses of the air spring due to various displacement excitations. The experimental results describe the detailed flow behavior of both valves. The flow characterization results can be incorporated as one of the most critical parameters for future model development of pneumatic systems. The tests indicate that the leveling valve with chambered design has a far faster transient flow response than the disk valve, although it is more complicated in its mechanical design and therefore costs more. To take advantage of the design simplicity of the disk valve, while also enabling it to have a faster transient response (compared with the chambered design), it is re-designed with larger flow openings and other elements to match the performance of the chambered valve for transient flow. A comparison of the experimental results and simulations validates that the re-designed rotary disk valve performs nearly the same as the chambered valve, but is simpler and costs less. The study's results are directly applicable to improving the transient dynamics of heavy truck air suspensions by providing a better understanding of how load-leveling valves can be used not only to provide ride-height control, but also to influence the roll and pitch dynamics of heavy trucks. Advisors/Committee Members: Ahmadian, Mehdi (committeechair), Southward, Steve C. (committee member), Mirzaeifar, Reza (committee member).

Subjects/Keywords: Air Suspension; Heavy Truck; Load-Leveling Valve; Flow Characterization

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APA (6^th Edition):

Zhu, Z. (2016). Flow Characterization and Redesign of Load-Leveling Valves for Improving Transient Dynamics of Heavy Truck Air Suspensions. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/73606

Chicago Manual of Style (16^th Edition):

Zhu, Zebo. “Flow Characterization and Redesign of Load-Leveling Valves for Improving Transient Dynamics of Heavy Truck Air Suspensions.” 2016. Masters Thesis, Virginia Tech. Accessed April 12, 2021. http://hdl.handle.net/10919/73606.

MLA Handbook (7^th Edition):

Zhu, Zebo. “Flow Characterization and Redesign of Load-Leveling Valves for Improving Transient Dynamics of Heavy Truck Air Suspensions.” 2016. Web. 12 Apr 2021.

Vancouver:

Zhu Z. Flow Characterization and Redesign of Load-Leveling Valves for Improving Transient Dynamics of Heavy Truck Air Suspensions. [Internet] [Masters thesis]. Virginia Tech; 2016. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10919/73606.

Council of Science Editors:

Zhu Z. Flow Characterization and Redesign of Load-Leveling Valves for Improving Transient Dynamics of Heavy Truck Air Suspensions. [Masters Thesis]. Virginia Tech; 2016. Available from: http://hdl.handle.net/10919/73606

University of Edinburgh

10. Richards, James Alexander. Friction and the flow of concentrated suspensions.

Degree: PhD, 2020, University of Edinburgh

URL: https://doi.org/10.7488/era/214 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.802356

► Suspensions are ubiquitous in industrial processing, yet fundamental understanding of how they flow remains limited. Recent progress on shear-thickening suspensions of non-Brownian particles establishes the… (more)

▼ Suspensions are ubiquitous in industrial processing, yet fundamental understanding of how they flow remains limited. Recent progress on shear-thickening suspensions of non-Brownian particles establishes the importance of direct mechanical contact and friction between particles. This represents a paradigm shift, linking wet suspensions to dry granular materials through a static jamming volume fraction. In this thesis I explore further the implications of mechanical contact in three ways. Firstly in time-dependent flows, I show that large shear-rate fluctuations arise from a competition between rapid microscopic contact dynamics and the slow dynamics controlling how the suspension is sheared. I develop a dynamical-systems approach that graphically shows how an instability arises, indicates how to control the instability, and allows the extraction of a contact relaxation time that is inaccessible to conventional rheometry. Next, more complex interparticle interactions are considered. I take the relevant effect to be a stress-dependent constraint on relative interparticle motion, e.g., sliding, twisting or rolling. Constraints lower the jamming volume fraction and can either form or break with stress. I show that an interplay between two constraint types can capture all classes of flow curve, with predictions compared against my own experimental or literature data. In particular, a yield stress behaviour is reproduced for rolling constraints being broken while sliding is constrained. Finally, I investigate the protocol dependence of yield-stress suspension rheology. The complex experimental phenomenology is shown to be consistent with an adhesively-bonded compressive frictional contact network. The yield stress is hence related to jamming and constraints, rather than just resulting from interparticle attraction. This finding continues the transition of non-Brownian suspension rheology from the colloidal to the granular frame and suggests novel ways to tune the yielding behaviour through the interparticle friction coefficient or flow protocols.

Subjects/Keywords: non-Brownian suspension; shear-induced jamming; unsteady flow; sticky particles; modelling

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

APA (6^th Edition):

Richards, J. A. (2020). Friction and the flow of concentrated suspensions. (Doctoral Dissertation). University of Edinburgh. Retrieved from https://doi.org/10.7488/era/214 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.802356

Chicago Manual of Style (16^th Edition):

Richards, James Alexander. “Friction and the flow of concentrated suspensions.” 2020. Doctoral Dissertation, University of Edinburgh. Accessed April 12, 2021. https://doi.org/10.7488/era/214 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.802356.

MLA Handbook (7^th Edition):

Richards, James Alexander. “Friction and the flow of concentrated suspensions.” 2020. Web. 12 Apr 2021.

Vancouver:

Richards JA. Friction and the flow of concentrated suspensions. [Internet] [Doctoral dissertation]. University of Edinburgh; 2020. [cited 2021 Apr 12]. Available from: https://doi.org/10.7488/era/214 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.802356.

Council of Science Editors:

Richards JA. Friction and the flow of concentrated suspensions. [Doctoral Dissertation]. University of Edinburgh; 2020. Available from: https://doi.org/10.7488/era/214 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.802356

University of Lund

11. Dong, Junhao. Numerical study of dense particle flows under planar shear.

Degree: 2020, University of Lund

URL: https://lup.lub.lu.se/record/63c26d05-089a-4621-af87-7988d2db73b3 ; https://portal.research.lu.se/ws/files/84303638/Junhao_only_kappa.pdf

► In this thesis I conducted numerical simulations to study the flow behavior of dense particle flows composed of hard particles under planar shear using the… (more)

▼ In this thesis I conducted numerical simulations to study the flow behavior of dense particle flows composed of hard particles under planar shear using the discrete element method. The simulations were carried out in two dimensional systems, where the particles are modelled as circular discs. The discs are non-Brownian and neutrally buoyant. The granular flows can be either dry or immersed in a Newtonian fluid, where the fluid is treated in a mean field manner and represented by a velocity profile. The works that are included in this thesis can be divided into two parts. The first (Paper I+II) focus on the rheology of discontinuous shear thickening (DST) granular flows under steady planar shear (i.e.~with a constant shear-rate). The DST behavior is reproduced using the critical load model (CLM), where a threshold force is introduced for determining whether there is friction between the discs at contact. A contact is frictional if the normal force between the discs is larger than the threshold. It is found that a key parameter that controls the rheology of such flow is the fraction of frictional contacts, defined as the ratio of the number of frictional contacts to the total number of contacts. By performing simulations under controlled imposed pressure, we are able to investigate behaviors of suspensions close to shear jamming points as well as suspensions with intermediate fraction of frictional contacts. The constitutive laws are then presented, which are used to predict rheology of discontinuous shear thickening particle flows under various shear protocols. The types of particle flows range from viscous suspensions where the particles are strictly overdamped so that the particle inertia are negligible to dry granular flows where the particle inertia are dominant, as well as suspensions where both particle inertia and viscous drag is important. The second part (Paper III and IV) focuses on the behaviors of dense viscous suspensions under oscillatory planar shear. The simulations wereconducted both with constant packing fraction and constant imposed pressure. The oscillatory shear is either a pure oscillation or with an extra oscillatory shear parallel to a primary shear. It is found that by having an oscillatory shear parallel to the primary shear, the viscosity of the suspensions decreased. Furthermore, the shear jamming packing fractions for the suspensions composed of frictional particles are found to be increased under oscillation conditions, possibly due to the microstructure of the suspensions.

Subjects/Keywords: Mechanical Engineering; dense suspension; granular flow; shear thickening; oscillatory flow; rheology; Discrete element method

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APA (6^th Edition):

Dong, J. (2020). Numerical study of dense particle flows under planar shear. (Doctoral Dissertation). University of Lund. Retrieved from https://lup.lub.lu.se/record/63c26d05-089a-4621-af87-7988d2db73b3 ; https://portal.research.lu.se/ws/files/84303638/Junhao_only_kappa.pdf

Chicago Manual of Style (16^th Edition):

Dong, Junhao. “Numerical study of dense particle flows under planar shear.” 2020. Doctoral Dissertation, University of Lund. Accessed April 12, 2021. https://lup.lub.lu.se/record/63c26d05-089a-4621-af87-7988d2db73b3 ; https://portal.research.lu.se/ws/files/84303638/Junhao_only_kappa.pdf.

MLA Handbook (7^th Edition):

Dong, Junhao. “Numerical study of dense particle flows under planar shear.” 2020. Web. 12 Apr 2021.

Vancouver:

Dong J. Numerical study of dense particle flows under planar shear. [Internet] [Doctoral dissertation]. University of Lund; 2020. [cited 2021 Apr 12]. Available from: https://lup.lub.lu.se/record/63c26d05-089a-4621-af87-7988d2db73b3 ; https://portal.research.lu.se/ws/files/84303638/Junhao_only_kappa.pdf.

Council of Science Editors:

Dong J. Numerical study of dense particle flows under planar shear. [Doctoral Dissertation]. University of Lund; 2020. Available from: https://lup.lub.lu.se/record/63c26d05-089a-4621-af87-7988d2db73b3 ; https://portal.research.lu.se/ws/files/84303638/Junhao_only_kappa.pdf

12. Audemar, Vassanti. Suspensions de globules rouges en micro-écoulement : rhéologie et occlusion : Micro-flows of red blood cell suspensions : rheology and occlusion.

Degree: Docteur es, Physique pour les sciences du vivant, 2017, Université Grenoble Alpes (ComUE)

URL: http://www.theses.fr/2017GREAY033

►

La microcirculation sanguine est un système constitué de réseaux complexesde vaisseaux sanguins de diamètres micrométriques. C’est le lieu privilégié deséchanges de gaz et de nutriments… (more)

▼

La microcirculation sanguine est un système constitué de réseaux complexesde vaisseaux sanguins de diamètres micrométriques. C’est le lieu privilégié deséchanges de gaz et de nutriments entre le sang et les tissus.Les écoulements dans ces réseaux sont gouvernés par les propriétés des constituantsdu sang c’est-à-dire des cellules en suspension dans du plasma et plus particulièrementdes globules rouges qui sont les cellules majoritaires dans le sang.Selon les conditions de l’écoulement, les globules rouges, qui sont des particulesdéformables, peuvent présenter différents types de formes et de dynamiques quiinfluencent la rhéologie de la suspension. Les interactions hydrodynamiques entreglobules rouges et avec les parois dans les vaisseaux confinés influencent égalementles écoulements à travers des phénomènes de diffusion mais aussi de structurationdes globules au sein de la suspension. Il a notamment été montré que des couchesde plasma dépourvues de globules rouges près des parois des vaisseaux sanguins induisentune diminution de la viscosité effective de la suspension lorsqu’on diminuele diamètre du vaisseau. Par ailleurs, des structurations en file ont également étéobservées dans la microcirculation sanguine avec des conséquences probables surla rhéologie. Au cours de ces travaux de thèse, nous avons investigué les propriétésrhéologiques de suspensions de globules rouges en micro-écoulement grâce à uneméthode de rhéométrie microfluidique. Nous avons focalisé notre attention sur larelation entre la rhéologie et la structuration de la suspension dans un canal, liéeau confinement ainsi qu’aux régimes dynamiques des globules en écoulement.Dans certains cas pathologiques comme la drépanocytose où les propriétés desglobules rouges peuvent être modifiées, les écoulements dans la microcirculationpeuvent être perturbés et conduire à des crises vaso-occlusives dont les mécanismesphysiques restent mal compris. Nous avons exploré la dynamique de formationd’occlusions et leurs évolutions dans des réseaux de canaux micrométriques modèlesavec des suspensions de globules rouges dont les propriétés ont été modifiées,révélant ainsi une dynamique complexe où l’adhésion et des effets d’obstructionsinterviennent.

Blood microcirculation consists in blood flowing in complex microvessel networks.Gas and nutrient exchanges between blood and tissues occur in these networks.Microcirculatory blood flows are governed by the properties of blood components,mainly red blood cells suspended in plasma. Red blood cells are deformableparticles which can exibit different shapes and motion dynamics that influence therheology. Hydrodynamic interactions between red blood cells and with walls of theconfined channels lead to diffusion and structuration in the suspension that alsoaffects the rheology. Plasma cell-free layers near walls observed in the microcirculationinduce a decrease of the effective viscosity with decreasing vessel diameter.Other types of structuration like layering of red blood cells have been observed inthe microcirculation with…

Advisors/Committee Members: Podgorski, Thomas (thesis director), Coupier, Gwennou (thesis director).

Subjects/Keywords: Suspension; Globule rouge; Micro-Écoulement; Rhéologie; Occusion; Microfluidique; Suspension; Red blood cell; Micro-Flow; Rheology; Occlusion; Microfluidique; 530

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APA (6^th Edition):

Audemar, V. (2017). Suspensions de globules rouges en micro-écoulement : rhéologie et occlusion : Micro-flows of red blood cell suspensions : rheology and occlusion. (Doctoral Dissertation). Université Grenoble Alpes (ComUE). Retrieved from http://www.theses.fr/2017GREAY033

Chicago Manual of Style (16^th Edition):

Audemar, Vassanti. “Suspensions de globules rouges en micro-écoulement : rhéologie et occlusion : Micro-flows of red blood cell suspensions : rheology and occlusion.” 2017. Doctoral Dissertation, Université Grenoble Alpes (ComUE). Accessed April 12, 2021. http://www.theses.fr/2017GREAY033.

MLA Handbook (7^th Edition):

Audemar, Vassanti. “Suspensions de globules rouges en micro-écoulement : rhéologie et occlusion : Micro-flows of red blood cell suspensions : rheology and occlusion.” 2017. Web. 12 Apr 2021.

Vancouver:

Audemar V. Suspensions de globules rouges en micro-écoulement : rhéologie et occlusion : Micro-flows of red blood cell suspensions : rheology and occlusion. [Internet] [Doctoral dissertation]. Université Grenoble Alpes (ComUE); 2017. [cited 2021 Apr 12]. Available from: http://www.theses.fr/2017GREAY033.

Council of Science Editors:

Audemar V. Suspensions de globules rouges en micro-écoulement : rhéologie et occlusion : Micro-flows of red blood cell suspensions : rheology and occlusion. [Doctoral Dissertation]. Université Grenoble Alpes (ComUE); 2017. Available from: http://www.theses.fr/2017GREAY033

KTH

13. Hirota, Masato. An Experimental Study of Fibre SuspensionFlows in Pipes using Nuclear MagneticResonance Imaging.

Degree: Mechanics, 2013, KTH

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-202628

► This study deals with fibre suspension flows through cylindrical pipes. Thepresent work aims at measurements of opaque flows, which are common inindustries. Nuclear magnetic… (more)

Subjects/Keywords: Fibre suspension; Multi-phase flow; Nuclear magnetic resonance; Engineering and Technology; Teknik och teknologier

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APA (6^th Edition):

Hirota, M. (2013). An Experimental Study of Fibre SuspensionFlows in Pipes using Nuclear MagneticResonance Imaging. (Thesis). KTH. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-202628

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):

Hirota, Masato. “An Experimental Study of Fibre SuspensionFlows in Pipes using Nuclear MagneticResonance Imaging.” 2013. Thesis, KTH. Accessed April 12, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-202628.

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

MLA Handbook (7^th Edition):

Hirota, Masato. “An Experimental Study of Fibre SuspensionFlows in Pipes using Nuclear MagneticResonance Imaging.” 2013. Web. 12 Apr 2021.

Vancouver:

Hirota M. An Experimental Study of Fibre SuspensionFlows in Pipes using Nuclear MagneticResonance Imaging. [Internet] [Thesis]. KTH; 2013. [cited 2021 Apr 12]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-202628.

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

Council of Science Editors:

Hirota M. An Experimental Study of Fibre SuspensionFlows in Pipes using Nuclear MagneticResonance Imaging. [Thesis]. KTH; 2013. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-202628

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

Delft University of Technology

14. Hageman, Tim (author). Heat transfer in finite sized particles suspensions.

Degree: 2017, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:127e6166-0974-4dc1-a9a7-7953fec3d510

► Heat transfer is important in many applications. For instance, due to the decrease in size of electronics, it becomes more necessary to have efficient and… (more)

▼ Heat transfer is important in many applications. For instance, due to the decrease in size of electronics, it becomes more necessary to have efficient and smaller cooling systems. In order to increase the effect of the cooling liquids used, it might be interesting to add extra solid particles with a high conductivity, to possibly increase the effective heat transfer fromthe wall to the liquid. These particles can be separated in 2 categories: point particles, with a very small size compared to the flow phenomena, and finite sized particles, which due to their larger size are able to significantly influence the fluid flow. In this thesis, the finite sized particles and their effect on the effective conductivity have been analyzed by using a CFD code. The main focus has been on the effect of the mechanical and thermal Stokes numbers, which give an indication about the time required for the particles to react to changes in surrounding flow and temperature compared to the relevant flow time scale. To investigate the effect of large particles on the effective conductivity of a fluid a numerical method to solve heat transfer inside a fluid and between fluid and particles has been implemented. This method, based on an immersed boundary method combined with DNS, is able to solve both isolated particles and extremely high conductivity particles. To solve the heat transfer for finite conductivities, a volume of fluid method has also been implemented. These methods have been verified by comparing the simulation results to known results for single sphere heat transfer and conservation of energy. With this code, the influence of the thermal and mechanical Stokes numbers have been analyzed for laminar Couette flow. In order to gain a better understanding of the underlying heat transfer mechanics, it has been assumed that the natural convection is negligible and the density ratio between the particle and the fluid is taken to be equal to one (no effects of gravity). From this it appeared that the effective conductivity of a suspension can be split in 3 components: the non-moving conductivity, an enhancement due to fluid convection induced by the particles and an increase in heat transfer due to particle convective heat transfer. The non-moving conductivity is only dependent on the conductivity of the particles and the fluid, and on the particle concentration. It stays close to constant independent of Stokes numbers. In contrast, the fluid convection appeared to scale significantly with the mechanical Stokes number and with the particle concentration. This appeared to be due to the increase in particle inertia resulting in more movement in wall normal direction and as a result moving more fluid in wall normal direction. The particle convection appeared to not only scale with the thermal Stokes number and the particle concentration, but also with the mechanical Stokes number. This increase was caused by the particles being… Advisors/Committee Members: Breugem, Wim-Paul (mentor), Delft University of Technology (degree granting institution).

Subjects/Keywords: Multiphase flow; Heat transfer; Suspension; finite-sized particles; Immersed boundary method; DNS; Volume of fluid

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

APA (6^th Edition):

Hageman, T. (. (2017). Heat transfer in finite sized particles suspensions. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:127e6166-0974-4dc1-a9a7-7953fec3d510

Chicago Manual of Style (16^th Edition):

Hageman, Tim (author). “Heat transfer in finite sized particles suspensions.” 2017. Masters Thesis, Delft University of Technology. Accessed April 12, 2021. http://resolver.tudelft.nl/uuid:127e6166-0974-4dc1-a9a7-7953fec3d510.

MLA Handbook (7^th Edition):

Hageman, Tim (author). “Heat transfer in finite sized particles suspensions.” 2017. Web. 12 Apr 2021.

Vancouver:

Hageman T(. Heat transfer in finite sized particles suspensions. [Internet] [Masters thesis]. Delft University of Technology; 2017. [cited 2021 Apr 12]. Available from: http://resolver.tudelft.nl/uuid:127e6166-0974-4dc1-a9a7-7953fec3d510.

Council of Science Editors:

Hageman T(. Heat transfer in finite sized particles suspensions. [Masters Thesis]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:127e6166-0974-4dc1-a9a7-7953fec3d510

15. Najuch, Tim Peter. Simulation of dense suspensions with discrete element method and a coupled lattice Boltzmann method.

Degree: PhD, 2019, University of Edinburgh

URL: http://hdl.handle.net/1842/35495

► Suspensions, mixtures of a fluid and particles, are widespread in nature and industry. A better understanding of suspension flow physics could be gained by accurate… (more)

▼ Suspensions, mixtures of a fluid and particles, are widespread in nature and industry. A better understanding of suspension flow physics could be gained by accurate simulations and hence, many different simulation techniques for fluid-solid flows have been proposed. The intention of this thesis is to establish an accurate, high-fidelity methodology to simulate sheared dense suspensions on microscale which allow for extraction of reliable data for macroscale models and better understanding of underlying physical processes. Therefore, two partially saturated coupled lattice Boltzmann discrete element methods (LBDEM) are analysed and evaluated with regard to the stresslet computation of suspension flow under simple shear at first. Simulation results for a single sphere, two spheres, and several hundred spheres, immersed in a sheared fluid show that a commonly used partially saturated method based on the non-equilibrium bounce-back lead to non-satisfactory results. But an alternative superposition method, which is mostly neglected in the literature, can result in accurate stresslet calculations. Furthermore, an ideal single relaxation parameter range for the fluid phase to reduce slip velocity effects is determined. Based on the stresslet study outcome, the superposition method is used to simulate two particle collisions in the second part of this work. Thereby, a careful assessment of the partially saturated LBDEM capabilities to resolve lubrication interactions between particles, which are important in suspension flows, is achieved. Moreover, a popular lubrication correction model, which is applied for very small gap distances between particles which cannot be resolved by the lattice size, is slightly modified and calibrated to be suitable when used with the partially saturated coupling method. In the third part of this thesis, a comparison between the expensive LBDEM coupling and a tremendously cheaper discrete element method (DEM) with a model for lubricated particle-particle interactions is carried out. It is shown that for low Reynolds number sheared suspensions, with intermediate to dense solid packing fractions, the differences between both aforementioned LBDEM and DEM approaches can be minor. Thus, it is demonstrated that a DEM with a lubrication model can be effectively used to simulate microscale processes of dense suspension under simple shear in a low Reynolds number regime for a significant lower fraction of the computational expenses necessary for LBDEM simulations. Hence, in the last part of this thesis, only a DEM with a lubrication model is employed to study particle-particle contact and lubrication interactions as well as the underlying dissipation mechanism in dense sheared suspensions on microscale. Thereby, providing evidence that the suspension bulk viscosity divergence is caused by the lubricated dissipative interactions while mechanical particle-particle contact is the stress dominating contribution for high solid fractions close to jamming.

Subjects/Keywords: fluid-particle flow simulations; viscosity; lubrication forces; lubrication force model; particles in suspension

10 more images…

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

APA (6^th Edition):

Najuch, T. P. (2019). Simulation of dense suspensions with discrete element method and a coupled lattice Boltzmann method. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/35495

Chicago Manual of Style (16^th Edition):

Najuch, Tim Peter. “Simulation of dense suspensions with discrete element method and a coupled lattice Boltzmann method.” 2019. Doctoral Dissertation, University of Edinburgh. Accessed April 12, 2021. http://hdl.handle.net/1842/35495.

MLA Handbook (7^th Edition):

Najuch, Tim Peter. “Simulation of dense suspensions with discrete element method and a coupled lattice Boltzmann method.” 2019. Web. 12 Apr 2021.

Vancouver:

Najuch TP. Simulation of dense suspensions with discrete element method and a coupled lattice Boltzmann method. [Internet] [Doctoral dissertation]. University of Edinburgh; 2019. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/1842/35495.

Council of Science Editors:

Najuch TP. Simulation of dense suspensions with discrete element method and a coupled lattice Boltzmann method. [Doctoral Dissertation]. University of Edinburgh; 2019. Available from: http://hdl.handle.net/1842/35495

Ohio University

16. Sarabian, Mohammad. Experimental Investigations and Direct Numerical Simulations of Rigid Particles in ShearFlows of Newtonian and Complex Fluids.

Degree: PhD, Mechanical Engineering (Engineering and Technology), 2020, Ohio University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1582821437191013

► The main objective of this dissertation is to provide well-resolved data to understand the dispersion of solid in inhomogeneous shear flows. To this end, accurate… (more)

▼ The main objective of this dissertation is to provide well-resolved data to understand the dispersion of solid in inhomogeneous shear flows. To this end, accurate experiments and high-fidelity computations are performed. On the experimental front, the dispersion of solid in curvilinear flows of Newtonian fluids is studied. The results show that in the absence of inertia, drag forces on the particles play an essential role in the dispersion of solid. Therefore, the first step to study the dispersion of solid in flows of non-linear or complex fluids is to determine drag forces on a particle when a stream is present normal to the mainstream flow direction. This gap in knowledge has established the computational part of this research. A summary of the performed research is as follows. Three-dimensional numerical simulations were performed to investigate the sedimentation of a single sphere in the absence and presence of a simple cross shear flow in a yield stress fluid with weak inertia. In our simulations, the settling flow is considered to be the primary flow, whereas the linear cross shear flow is a secondary flow with amplitude 10% of the primary flow. To study the effects of elasticity and plasticity of the carrying fluid on the sphere drag as well as the flow dynamics, the fluid is modeled using the elastovisco-plastic (EVP) constitutive laws proposed by Saramito [Sar09]. The extra non-Newtonian stress tensor is fully coupled with the flow equation and the solid particle is represented by an immersed boundary (IB) method. Our results show that the fore-aft asymmetry in the velocity is less pronounced and the negative wake disappears when a linear cross shear flow is applied. It is found that the drag on a sphere settling in a sheared yield stress fluid is reduced significantly as compared to an otherwise quiescent fluid. More importantly, the sphere drag in the presence of a secondary cross shear flow cannot be derived from the pure sedimentation drag law owing to the non-linear coupling between the simple shear flow and the uniform flow. Finally, it is shown that the drag on the sphere settling in a sheared yield-stress fluid is reduced at higher material elasticity mainly due to the form and viscous drag reduction.Particle migration in a non-Brownian suspension sheared in a Taylor-Couette configuration and in the limit of vanishing Reynolds number has been experimentally investigated. Highly resolved index-matching techniques are used to measure the local particulate volume fraction. In this wide-gap Taylor-Couette configuration, it is found that for a large range of bulk volume fraction, phi_b= 20%-50%], the fully developed concentration profiles are well predicted by the Suspension Balance Model (SBM) of Nott & Brady [NB94]. Moreover, systematic measurements of the migration strain scale and of the migration amplitude are provided which highlight the limits of the SBM predictions. Finally, the wall-effects on the particle migration in a non-Brownian suspension sheared in a wide-gap Taylor-Couette cell are… Advisors/Committee Members: Hormozi, Sarah (Advisor).

Subjects/Keywords: Mechanical Engineering; Suspension; Migration; SBM; Sedimentation, EVP; IBM; Sphere drag; Shear flow

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APA (6^th Edition):

Sarabian, M. (2020). Experimental Investigations and Direct Numerical Simulations of Rigid Particles in ShearFlows of Newtonian and Complex Fluids. (Doctoral Dissertation). Ohio University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1582821437191013

Chicago Manual of Style (16^th Edition):

Sarabian, Mohammad. “Experimental Investigations and Direct Numerical Simulations of Rigid Particles in ShearFlows of Newtonian and Complex Fluids.” 2020. Doctoral Dissertation, Ohio University. Accessed April 12, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1582821437191013.

MLA Handbook (7^th Edition):

Sarabian, Mohammad. “Experimental Investigations and Direct Numerical Simulations of Rigid Particles in ShearFlows of Newtonian and Complex Fluids.” 2020. Web. 12 Apr 2021.

Vancouver:

Sarabian M. Experimental Investigations and Direct Numerical Simulations of Rigid Particles in ShearFlows of Newtonian and Complex Fluids. [Internet] [Doctoral dissertation]. Ohio University; 2020. [cited 2021 Apr 12]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1582821437191013.

Council of Science Editors:

Sarabian M. Experimental Investigations and Direct Numerical Simulations of Rigid Particles in ShearFlows of Newtonian and Complex Fluids. [Doctoral Dissertation]. Ohio University; 2020. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1582821437191013

17. Liedtke, Anne-Kathrin. Study of a new gas-liquid-solid three phase contact mode at millimetric scale : catalytic reactors using “slurry Taylor” flow : Étude d'un nouveau mode de contact gaz-liquide-solide à l'échelle millimétrique : vers des réacteurs catalytiques utilisant l'écoulement "slurry Taylor".

Degree: Docteur es, Génie des procédés, 2014, Université Claude Bernard – Lyon I

URL: http://www.theses.fr/2014LYO10137

►

Des réacteurs avec solide en suspension (« slurry »), très répandu dans l'industrie chimique, du laboratoire à la production, offrent des bonnes capacités en transfert… (more)

▼

Des réacteurs avec solide en suspension (« slurry »), très répandu dans l'industrie chimique, du laboratoire à la production, offrent des bonnes capacités en transfert de matière et de chaleur. Leur flexibilité facilite le changement de la phase solide et permet une régénération en continue des catalyseurs en cas de désactivation. Cependant, ils présentent un fort rétro-mélange, et donc un désavantage pour des réactions ayant des enjeux de sélectivité et/ou de conversion poussées. L'écoulement segmenté dit de Taylor est souvent mis en œuvre dans les réacteurs micro-structurés (RMS), grâce à ses propriétés intéressantes (capacités de transfert, écoulement, piston). Cependant, l'utilisation des solides catalytiques dans ces RMS est le plus souvent résolue par immobilisation du catalyseur nuisant la flexibilité. L'écoulement « slurry Taylor » (EST) qui utilise les recirculations internes dans les segments liquides pour transporter des particules en poudre, peut potentiellement répondre à cet enjeu. L'objet de cette étude est la conception et la caractérisation de ce nouveau mode de contact gaz-liquide-solide (G-L-S) dans des tubes millimétriques horizontaux et verticaux. Des études hydrodynamiques ont révélé différents régimes d'écoulement dépendant de la vitesse et de l'orientation de l'écoulement. Pour étudier le transfert de matière L-S, une résine échangeuse d'ion a été utilisée et une première corrélation pour le nombre de Sherwood est proposée

Slurry reactors, widely encountered in chemical industry (laboratory scale up to manufactaring), offer good mass and heat transfer capacities and their high flexibility ensures the simple changeover of solid phases enables a continuous online fresh catalyst feed for fast deactivating catalysts. However slurry reactors promote a high degree of backmixing which can be a drawback for reactions with selectivity issues or when very high conversions are required. In microreaction technology, Taylor flow is often employed providing excellent heat and mass transfer and almost ideal plug flow behavior. Solid handing in these small structures is often resolved by immobilizing the solid catalyst which impinges on the flexibility. One possible solution to combine beneficial properties of Taylor flow with the operational flexibility of conventional slurry reactors is a “slurry Taylor” flow (STF) where catalyst particles are suspended and kept in motion by the internal circulations present in the liquid slugs. The focus of this work is the design and characterization of this innovative gas-liquid-solid contactor. Particles were transported in millimetric horizontal and vertical tubing without the risk of clogging. Hydrodynamic studies revealed different flow patterns depending mainly on velocity and flow orientation. Ion exchange resin particles were used to study the liquid-solid mass transfer and first correlation for the Sherwood number in STF is proposed

Advisors/Committee Members: Bellefon, Claude de (thesis director).

Subjects/Keywords: Écoulement Taylor; Transfert de matière; Hydrodynamique; Catalyse hétérogène; Réacteurs slurry; Micro réacteur; Suspension; Taylor flow; Mass transfer; Hydrodynamic; Heterogeneous catalysis; Slurry reactors; Microreactor; Suspension; 660.2

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APA (6^th Edition):

Liedtke, A. (2014). Study of a new gas-liquid-solid three phase contact mode at millimetric scale : catalytic reactors using “slurry Taylor” flow : Étude d'un nouveau mode de contact gaz-liquide-solide à l'échelle millimétrique : vers des réacteurs catalytiques utilisant l'écoulement "slurry Taylor". (Doctoral Dissertation). Université Claude Bernard – Lyon I. Retrieved from http://www.theses.fr/2014LYO10137

Chicago Manual of Style (16^th Edition):

Liedtke, Anne-Kathrin. “Study of a new gas-liquid-solid three phase contact mode at millimetric scale : catalytic reactors using “slurry Taylor” flow : Étude d'un nouveau mode de contact gaz-liquide-solide à l'échelle millimétrique : vers des réacteurs catalytiques utilisant l'écoulement "slurry Taylor".” 2014. Doctoral Dissertation, Université Claude Bernard – Lyon I. Accessed April 12, 2021. http://www.theses.fr/2014LYO10137.

MLA Handbook (7^th Edition):

Liedtke, Anne-Kathrin. “Study of a new gas-liquid-solid three phase contact mode at millimetric scale : catalytic reactors using “slurry Taylor” flow : Étude d'un nouveau mode de contact gaz-liquide-solide à l'échelle millimétrique : vers des réacteurs catalytiques utilisant l'écoulement "slurry Taylor".” 2014. Web. 12 Apr 2021.

Vancouver:

Liedtke A. Study of a new gas-liquid-solid three phase contact mode at millimetric scale : catalytic reactors using “slurry Taylor” flow : Étude d'un nouveau mode de contact gaz-liquide-solide à l'échelle millimétrique : vers des réacteurs catalytiques utilisant l'écoulement "slurry Taylor". [Internet] [Doctoral dissertation]. Université Claude Bernard – Lyon I; 2014. [cited 2021 Apr 12]. Available from: http://www.theses.fr/2014LYO10137.

Council of Science Editors:

Liedtke A. Study of a new gas-liquid-solid three phase contact mode at millimetric scale : catalytic reactors using “slurry Taylor” flow : Étude d'un nouveau mode de contact gaz-liquide-solide à l'échelle millimétrique : vers des réacteurs catalytiques utilisant l'écoulement "slurry Taylor". [Doctoral Dissertation]. Université Claude Bernard – Lyon I; 2014. Available from: http://www.theses.fr/2014LYO10137

INP Toulouse

18. Wang, Guiquan. Modulation of wall-bounded turbulent flows by large particles : effect of concentration, inertia, and shape : Modification des écoulements turbulents avec paroi, par les particules de taille finie : effet de leur concentration, forme et inertie.

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

URL: http://www.theses.fr/2017INPT0079

► L’effet des inclusions sur la turbulence de l’écoulement est un élément clé à comprendre afin de maîtriser le transport de milieux dispersés, dans le domaine… (more)

▼ L’effet des inclusions sur la turbulence de l’écoulement est un élément clé à comprendre afin de maîtriser le transport de milieux dispersés, dans le domaine du génie pétrolier, environnemental, agroalimentaire, génie de la réaction chimique ou transformation du solide. Les expériences de Matas et al. (PRL, 2003) ont mis en évidence un effet non monotone des particules isodenses (de densité égale à celle du fluide) sur la transition laminaire-turbulent, cet effet dépendant de la taille des particules et de leur concentration dans la suspension. Une petite quantité de particules de taille finie s’est avérée suffisante pour diminuer considérablement le seuil de transition laminaire turbulent. Nous avons utilisé des simulations numériques, basées sur une approche de type “Force Coupling Method” afin de comprendre cet effet. Les domaines de simulations étaient choisis pour accommoder le minimum de structures cohérentes suffisantes pour entretenir la turbulence. Nous avons particulièrement étudié la corrélation entre le comportement instationnaire de l’écoulement et la distribution instantanée de particules, en fonction de la configuration de l’écoulement (Couette plan ou écoulement en canal), de la forme des particules ainsi que leur inertie et concentration. Dans un écoulement de Couette plan turbulent, la contrainte pariétale est augmentée en présence des particules. Les profiles (dans la direction normale aux parois) de vitesse moyenne et des contraintes de Reynolds ne sont pas significativement modifiés en présence des particules, si la viscosité du fluide est remplacée par la viscosité effective de la suspension dans le calcul du nombre de Reynolds de l’écoulement. Par contre l’analyse temporelle et modale des fluctuations de l’écoulement suggère que les particules modifient légèrement le cycle de régénération de la turbulence, à travers l’augmentation d’énergie à petites échelles. En effet, la forme des streaks et le caractère intermittent de l’écoulement sont impactés par la présence des particules, surtout quand elles sont inertielles (de densité supérieure à celle du fluide). Ces résultats ont été publiés dans le journal Physical Review F (Wang et al., 2017). En outre, nous avons montré qu’à fraction volumique égale, les propriétés d’écoulement turbulent des suspensions de particules sphéroïdales de rapport de taille compris entre 0.5 et 2, sont similaires à celles des suspensions de particules sphériques. Le transfert de particules entre les différentes structures cohérentes de l’écoulement est analysé à la fin de la thèse. Néanmoins dans un écoulement en canal, les particules iso denses augmentent l’intensité des contraintes de Reynolds dans le plan transverse. Nous montrons que par leur concentration préférentielle dans les structures cohérentes à côté des parois (les éjections), elles influencent significativement le cycle de régénération en agissant sur tous les processus à la fois linéaires et non linéaires du cycle: la formation des streaks, puis leur rupture et la régénération des vortex alignés avec… Advisors/Committee Members: Climent, Éric (thesis director), Abbas, Micheline (thesis director).

Subjects/Keywords: Ecoulement de suspension; Interactions hydrodynamiques; Particules non sphériques; Turbulence; Simulations numériques; Force Coupling Method; Suspension flow; Hydrodynamic Interactions; Non-spherical particles; Turbulence; Numerical simulation; Force Coupling Method

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

APA (6^th Edition):

Wang, G. (2017). Modulation of wall-bounded turbulent flows by large particles : effect of concentration, inertia, and shape : Modification des écoulements turbulents avec paroi, par les particules de taille finie : effet de leur concentration, forme et inertie. (Doctoral Dissertation). INP Toulouse. Retrieved from http://www.theses.fr/2017INPT0079

Chicago Manual of Style (16^th Edition):

Wang, Guiquan. “Modulation of wall-bounded turbulent flows by large particles : effect of concentration, inertia, and shape : Modification des écoulements turbulents avec paroi, par les particules de taille finie : effet de leur concentration, forme et inertie.” 2017. Doctoral Dissertation, INP Toulouse. Accessed April 12, 2021. http://www.theses.fr/2017INPT0079.

MLA Handbook (7^th Edition):

Wang, Guiquan. “Modulation of wall-bounded turbulent flows by large particles : effect of concentration, inertia, and shape : Modification des écoulements turbulents avec paroi, par les particules de taille finie : effet de leur concentration, forme et inertie.” 2017. Web. 12 Apr 2021.

Vancouver:

Wang G. Modulation of wall-bounded turbulent flows by large particles : effect of concentration, inertia, and shape : Modification des écoulements turbulents avec paroi, par les particules de taille finie : effet de leur concentration, forme et inertie. [Internet] [Doctoral dissertation]. INP Toulouse; 2017. [cited 2021 Apr 12]. Available from: http://www.theses.fr/2017INPT0079.

Council of Science Editors:

Wang G. Modulation of wall-bounded turbulent flows by large particles : effect of concentration, inertia, and shape : Modification des écoulements turbulents avec paroi, par les particules de taille finie : effet de leur concentration, forme et inertie. [Doctoral Dissertation]. INP Toulouse; 2017. Available from: http://www.theses.fr/2017INPT0079

INP Toulouse

19. Harang, Alice. Modélisation numérique de la mise en suspension de sédiments cohésifs par instabilités de cisaillement : Numerical modeling of cohesive sediment suspension by shear instabilities.

Degree: Docteur es, Océan, atmosphère, surfaces continentales, 2013, INP Toulouse

URL: http://www.theses.fr/2013INPT0016

►

Ce travail numérique porte sur le comportement de la lutocline (interface entre l'eau et la vase fluide) en écoulement cisaillé et vise à une meilleure… (more)

▼

Ce travail numérique porte sur le comportement de la lutocline (interface entre l'eau et la vase fluide) en écoulement cisaillé et vise à une meilleure compréhension des mécanismes de remise en suspension de sédiments cohésifs. La crème de vase, ou vase partiellement solidifiée, est modélisée par un fluide homogène équivalent miscible dans l'eau, de rhéologie newtonienne ou viscoplastique. Une étude de l'hydrodynamique de cet écoulement stratifié en densité ainsi qu'en viscosité est ensuite proposée. Considérant une crème de vase initialement non-turbulente, l'étude se focalise sur le développement des instabilités au niveau de la lutocline et de la transition vers une couche de mélange turbulente. La particularité de cet écoulement réside dans la forte viscosité de vase et son seuil de mise en mouvement lorsqu'elle présente un caractère viscoplastique. Une étude de stabilité linéaire permet d'évaluer l'influence des différents paramètres de l'écoulement, notamment les stratifications en densité et en viscosité. La stratification en viscosité augmente sensiblement le taux de croissance de l'instabilité pour des nombres de Reynolds intermédiaires. L'évolution non-linéaire de l'écoulement est ensuite étudiée en utilisant des simulations numériques directes, la stratification en viscosité entrainant un épaississement de la couche de mélange finale. Enfin, des simulations numériques directes basées sur un modèle de fluide de Bingham régularisé permettent d'étudier l'influence de la contrainte seuil sur le développement de l'instabilité.

This numerical study focuses on the behavior of the lutocline in a shear flow and aims to better understand the mechanism of resuspension of cohesive sediment. Mud flow, or mud partially consolidated, is modeled by an equivalent homogenous fluid miscible in water, with newtonian or viscoplastic rheology. A study of the hydrodynamics of this shear flow, stratified both in density and viscosity, is presented. Considering an initially laminar mud flow, the focus of the study is on the development of instabilities on the lutocline and the transition to a turbulent mixing layer. The specificity of this flow lies on the large viscosity of the mud and its threshold to be put in motion, when it presents a viscoplastic feature. A linear stability study assesses the influence of the various parameters of the flow, especially of density and viscosity stratification. The viscosity stratification slightly increases the growth rate of the instability for intermediate Reynolds numbers. Then, the non linear evolution of the flow is studied by using direct numerical simulations, viscous stratification leading to a thicker mixing layer. At last, direct numerical simulations based on a Bingham regularized model, permits to study the influence of the critical strain on the development of the instability.

Advisors/Committee Members: Thual, Olivier (thesis director).

Subjects/Keywords: Instabilité de cisaillement; Transition vers la turbulence; Sédiment cohésif (crème de vase)- Mélange et dispersion; Écoulement stratifié; Écoulement géophysique; Estuaire; Mise en suspension; Shear instability; Transition to turbulence; Cohesive sediment (mud flow); Mixing and dispersion; Statified flow; Geophysical flow; Estuary; Suspension

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

APA (6^th Edition):

Harang, A. (2013). Modélisation numérique de la mise en suspension de sédiments cohésifs par instabilités de cisaillement : Numerical modeling of cohesive sediment suspension by shear instabilities. (Doctoral Dissertation). INP Toulouse. Retrieved from http://www.theses.fr/2013INPT0016

Chicago Manual of Style (16^th Edition):

Harang, Alice. “Modélisation numérique de la mise en suspension de sédiments cohésifs par instabilités de cisaillement : Numerical modeling of cohesive sediment suspension by shear instabilities.” 2013. Doctoral Dissertation, INP Toulouse. Accessed April 12, 2021. http://www.theses.fr/2013INPT0016.

MLA Handbook (7^th Edition):

Harang, Alice. “Modélisation numérique de la mise en suspension de sédiments cohésifs par instabilités de cisaillement : Numerical modeling of cohesive sediment suspension by shear instabilities.” 2013. Web. 12 Apr 2021.

Vancouver:

Harang A. Modélisation numérique de la mise en suspension de sédiments cohésifs par instabilités de cisaillement : Numerical modeling of cohesive sediment suspension by shear instabilities. [Internet] [Doctoral dissertation]. INP Toulouse; 2013. [cited 2021 Apr 12]. Available from: http://www.theses.fr/2013INPT0016.

Council of Science Editors:

Harang A. Modélisation numérique de la mise en suspension de sédiments cohésifs par instabilités de cisaillement : Numerical modeling of cohesive sediment suspension by shear instabilities. [Doctoral Dissertation]. INP Toulouse; 2013. Available from: http://www.theses.fr/2013INPT0016

Kyoto University / 京都大学

20. Iwashita, Takuya. Computational Studies on the Dynamics of Small-Particle Suspensions using Meso-Scale Modeling : メソスケールモデリングによる微粒子懸濁液のダイナミクスに関する計算科学的研究.

Degree: 博士(工学), 2009, Kyoto University / 京都大学

URL: http://hdl.handle.net/2433/77956 ; http://dx.doi.org/10.14989/doctor.k14589

新制・課程博士

甲第14589号

工博第3057号

Subjects/Keywords: Suspension; thermal fluctuations; shear flow; direct numerical simulation

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APA (6^th Edition):

Iwashita, T. (2009). Computational Studies on the Dynamics of Small-Particle Suspensions using Meso-Scale Modeling : メソスケールモデリングによる微粒子懸濁液のダイナミクスに関する計算科学的研究. (Thesis). Kyoto University / 京都大学. Retrieved from http://hdl.handle.net/2433/77956 ; http://dx.doi.org/10.14989/doctor.k14589

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):

Iwashita, Takuya. “Computational Studies on the Dynamics of Small-Particle Suspensions using Meso-Scale Modeling : メソスケールモデリングによる微粒子懸濁液のダイナミクスに関する計算科学的研究.” 2009. Thesis, Kyoto University / 京都大学. Accessed April 12, 2021. http://hdl.handle.net/2433/77956 ; http://dx.doi.org/10.14989/doctor.k14589.

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

MLA Handbook (7^th Edition):

Iwashita, Takuya. “Computational Studies on the Dynamics of Small-Particle Suspensions using Meso-Scale Modeling : メソスケールモデリングによる微粒子懸濁液のダイナミクスに関する計算科学的研究.” 2009. Web. 12 Apr 2021.

Vancouver:

Iwashita T. Computational Studies on the Dynamics of Small-Particle Suspensions using Meso-Scale Modeling : メソスケールモデリングによる微粒子懸濁液のダイナミクスに関する計算科学的研究. [Internet] [Thesis]. Kyoto University / 京都大学; 2009. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/2433/77956 ; http://dx.doi.org/10.14989/doctor.k14589.

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

Council of Science Editors:

Iwashita T. Computational Studies on the Dynamics of Small-Particle Suspensions using Meso-Scale Modeling : メソスケールモデリングによる微粒子懸濁液のダイナミクスに関する計算科学的研究. [Thesis]. Kyoto University / 京都大学; 2009. Available from: http://hdl.handle.net/2433/77956 ; http://dx.doi.org/10.14989/doctor.k14589

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

21. Singh, Vikram. Tuning Rigid Particle Motion In Simple Shear Flow And Soft Particle On A Curved Surface.

Degree: PhD, Chemical Engineering, 2013, Cornell University

URL: http://hdl.handle.net/1813/34188

► This thesis focuses on problems in microhydrodynamics involving both rigid and deformable particles. Two problems deal with the rotational behavior of thin particles at low… (more)

▼ This thesis focuses on problems in microhydrodynamics involving both rigid and deformable particles. Two problems deal with the rotational behavior of thin particles at low aspect ratio in linear flows. Two other problems focus on studying the collision and aggregation dynamics of non-spherical particles. Another problem involves studying the motion of a deformable particle on a rigid curved surface. In chapter 2, the ideal collision rate of cylindrical particles of circular crosssection in simple shear flow is studied. The work extends Smoluchowski's results for spherical particles to cylindrical particles. Asymptotic solutions are obtained for collision rate of particles of very large and very low aspect ratio. Numerical simulations are performed to obtain collision rate of particles of finite aspect ratio. In chapter 3, the rotational behavior of thin disks in linear flow at low Reynolds number is studied. Using numerical simulations and asymptotic analysis, the work estimates the effective aspect ratio of thin particles. In chapter 4, a class of rigid thin particles is identified which stops rotating in simple shear flow. Numerical simulations and analytical results are used to estimate the aspect ratio at which the particle stops tumbling and the angle at which the particle will align. In chapter 5, aggregation kinetics of red blood cells in the presence of macro- molecules is studied. Experiments are performed to study red blood cell dimer formation in microchannels to estimate the dependence of rate constant of aggregation of deformable particles on shear rate and macromolecule concentration. In chapter 6, dynamics of a deformable particle on a rigid curved surface is studied. It is shown that the colloidal interaction energy of a deformable particle on a rigid surface can be tuned by tuning its curvature. Migration velocity of the particle on the rigid surface due to its change in curvature is estimated analytically in some asymptotic limits. Advisors/Committee Members: Stroock, Abraham Duncan (chair), King, Michael R. (committee member), Koch, Donald L (committee member).

Subjects/Keywords: Low Reynolds number flow; Suspension; Deformable particles

…particles in simple shear flow at low Re number A number of diverse properties of suspension… …particle in simple shear flow to calculate the viscosity of the suspension at small dilution. A… …flow. The rate of collisions per unit volume per unit time in a suspension of singlet… …1 Introduction 1.1 Rigid non-spherical particles in simple shear flow at low Re number 1.2… …collision of cylinders in simple shear flow 2.1 Introduction…

11 more images…

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

APA (6^th Edition):

Singh, V. (2013). Tuning Rigid Particle Motion In Simple Shear Flow And Soft Particle On A Curved Surface. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/34188

Chicago Manual of Style (16^th Edition):

Singh, Vikram. “Tuning Rigid Particle Motion In Simple Shear Flow And Soft Particle On A Curved Surface.” 2013. Doctoral Dissertation, Cornell University. Accessed April 12, 2021. http://hdl.handle.net/1813/34188.

MLA Handbook (7^th Edition):

Singh, Vikram. “Tuning Rigid Particle Motion In Simple Shear Flow And Soft Particle On A Curved Surface.” 2013. Web. 12 Apr 2021.

Vancouver:

Singh V. Tuning Rigid Particle Motion In Simple Shear Flow And Soft Particle On A Curved Surface. [Internet] [Doctoral dissertation]. Cornell University; 2013. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/1813/34188.

Council of Science Editors:

Singh V. Tuning Rigid Particle Motion In Simple Shear Flow And Soft Particle On A Curved Surface. [Doctoral Dissertation]. Cornell University; 2013. Available from: http://hdl.handle.net/1813/34188

INP Toulouse

22. Loisel, Vincent. Transition à la turbulence des écoulements de suspension : simulations numériques et analyse physique : Transition to turbulence in suspension flows : numerical simulations and physical analysis.

Degree: Docteur es, Génie des Procédés et de l'Environnement, 2013, INP Toulouse

URL: http://www.theses.fr/2013INPT0147

► Le travail de cette thèse aborde le sujet de l’influence des particules non-pesantes et de taille macroscopique sur les écoulements en canal dans des conditions… (more)

▼ Le travail de cette thèse aborde le sujet de l’influence des particules non-pesantes et de taille macroscopique sur les écoulements en canal dans des conditions proches du seuil de la transition laminaire-turbulent. Les suspensions sont faiblement concentrées (fraction volumique φ = 5%). Le couplage hydrodynamique existant entre la phase dispersée et la phase continue est résolu numériquement par la Force-Coupling Method, et les particules sont suivies d’une façon lagrangienne. Dans un écoulement laminaire de Couette ou de Poiseuille plan, nous montrons que les contraintes induites par la phase solide augmentent avec l’inertie, et l’influence de la concentration est plus faible qu’en régime de Stokes. Les particules avancent avec un retard dans la direction de l’écoulement et migrent à travers les lignes de courant (effet Segré-Silberberg en Poiseuille). Les vitesses de migration et de glissement s’amplifient avec l’inertie et sont du même ordre de grandeur quand Rep = O(1). Quand les particules sont lâchées librement dans un écoulement de Poiseuille plan en-deça du seuil critique de transition à la turbulence, la suspension initiale- ment homogène (φ = 5%) devient stratifiée, après un temps d’écoulement de plusieurs dizaines d’unités de temps (rapport de la hauteur du canal sur la vitesse moyenne de l’écoulement). Après une centaine d’unités de temps, nous observons le développement d’une instabilité à l’interface entre la zone chargée en particules et la zone de fluide pur. Des motifs dunaires prennent place dans la direction de la vorticité. Ces motifs sont soutenus par des écoulements secondaires d’intensités faibles mais non-nulles. Dans un écoulement au-dessus du seuil de transition, nous avons étudié les profils des phases continues et dispersées et réalisé des visualisations 3D afin de comprendre pourquoi les particules macroscopiques diminuent le nombre de Reynolds critique de relaminarisation de l’écoulement. Nous observons que les particules provoquent une augmentation significative des fluctuations de vitesses dans les directions transverses et qu’elles modifient les structures rotationnelles de l’écoulement, qui deviennent plus petites, plus nombreuses et plus énergétiques (plus grandes vitesses de rotation). Le coefficient de frottement pariétal de l’écoulement de suspension en régime de transition est supérieur à celui de l’écoulement monophasique. Quand le nombre de Reynolds est diminué et que l’écoulement devient finalement laminaire, le coefficient de frottement pariétal rejoint la loi laminaire d’un écoulement monophasique, à condition de substituer la viscosité effective de la suspension à la viscosité du fluide dans l’expression du nombre de Reynolds. D’après nos résultats, la turbulence de l’écoulement de suspension est conservée jusqu’à des nombres de Reynolds bien inférieurs à celui de l’écoulement monophasique en canal, en accord avec les observations ex- périmentales de Matas, Morris et Guazzelli (PRL, 2003) pour une géométrie cylindrique. Par ailleurs, nous montrons que selon le sens de la… Advisors/Committee Members: Masbernat, Olivier (thesis director), Abbas, Micheline (thesis director).

Subjects/Keywords: Écoulements diphasiques; Simulation numérique; Particule; Taille finie; Suspension concentrée; Turbulence; Transition; Migration; Transition; Turbulence; Two-phase particulate flow; Numerical simulation

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

APA (6^th Edition):

Loisel, V. (2013). Transition à la turbulence des écoulements de suspension : simulations numériques et analyse physique : Transition to turbulence in suspension flows : numerical simulations and physical analysis. (Doctoral Dissertation). INP Toulouse. Retrieved from http://www.theses.fr/2013INPT0147

Chicago Manual of Style (16^th Edition):

Loisel, Vincent. “Transition à la turbulence des écoulements de suspension : simulations numériques et analyse physique : Transition to turbulence in suspension flows : numerical simulations and physical analysis.” 2013. Doctoral Dissertation, INP Toulouse. Accessed April 12, 2021. http://www.theses.fr/2013INPT0147.

MLA Handbook (7^th Edition):

Loisel, Vincent. “Transition à la turbulence des écoulements de suspension : simulations numériques et analyse physique : Transition to turbulence in suspension flows : numerical simulations and physical analysis.” 2013. Web. 12 Apr 2021.

Vancouver:

Loisel V. Transition à la turbulence des écoulements de suspension : simulations numériques et analyse physique : Transition to turbulence in suspension flows : numerical simulations and physical analysis. [Internet] [Doctoral dissertation]. INP Toulouse; 2013. [cited 2021 Apr 12]. Available from: http://www.theses.fr/2013INPT0147.

Council of Science Editors:

Loisel V. Transition à la turbulence des écoulements de suspension : simulations numériques et analyse physique : Transition to turbulence in suspension flows : numerical simulations and physical analysis. [Doctoral Dissertation]. INP Toulouse; 2013. Available from: http://www.theses.fr/2013INPT0147

Georgia Tech

23. Xu, Hanjiang. Measurement of fiber suspension flow and forming jet velocity profile by pulsed ultrasonic doppler velocimetry.

Degree: PhD, Institute of Paper Science and Technology, 2003, Georgia Tech

URL: http://hdl.handle.net/1853/7073

► The flow of wood fiber suspensions plays an important role during the pulp and paper manufacture process. Considerable research has been carried out in the… (more)

Subjects/Keywords: Fibers; Suspension; Fluid flow; Forming; Jets; Velocity measurement

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APA (6^th Edition):

Xu, H. (2003). Measurement of fiber suspension flow and forming jet velocity profile by pulsed ultrasonic doppler velocimetry. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/7073

Chicago Manual of Style (16^th Edition):

Xu, Hanjiang. “Measurement of fiber suspension flow and forming jet velocity profile by pulsed ultrasonic doppler velocimetry.” 2003. Doctoral Dissertation, Georgia Tech. Accessed April 12, 2021. http://hdl.handle.net/1853/7073.

MLA Handbook (7^th Edition):

Xu, Hanjiang. “Measurement of fiber suspension flow and forming jet velocity profile by pulsed ultrasonic doppler velocimetry.” 2003. Web. 12 Apr 2021.

Vancouver:

Xu H. Measurement of fiber suspension flow and forming jet velocity profile by pulsed ultrasonic doppler velocimetry. [Internet] [Doctoral dissertation]. Georgia Tech; 2003. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/1853/7073.

Council of Science Editors:

Xu H. Measurement of fiber suspension flow and forming jet velocity profile by pulsed ultrasonic doppler velocimetry. [Doctoral Dissertation]. Georgia Tech; 2003. Available from: http://hdl.handle.net/1853/7073

Kyoto University

24. Iwashita, Takuya. Computational Studies on the Dynamics of Small-Particle Suspensions using Meso-Scale Modeling .

Degree: 2009, Kyoto University

URL: http://hdl.handle.net/2433/77956

Subjects/Keywords: Suspension; thermal fluctuations; shear flow; direct numerical simulation

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APA (6^th Edition):

Iwashita, T. (2009). Computational Studies on the Dynamics of Small-Particle Suspensions using Meso-Scale Modeling . (Thesis). Kyoto University. Retrieved from http://hdl.handle.net/2433/77956

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):

Iwashita, Takuya. “Computational Studies on the Dynamics of Small-Particle Suspensions using Meso-Scale Modeling .” 2009. Thesis, Kyoto University. Accessed April 12, 2021. http://hdl.handle.net/2433/77956.

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

MLA Handbook (7^th Edition):

Iwashita, Takuya. “Computational Studies on the Dynamics of Small-Particle Suspensions using Meso-Scale Modeling .” 2009. Web. 12 Apr 2021.

Vancouver:

Iwashita T. Computational Studies on the Dynamics of Small-Particle Suspensions using Meso-Scale Modeling . [Internet] [Thesis]. Kyoto University; 2009. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/2433/77956.

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

Council of Science Editors:

Iwashita T. Computational Studies on the Dynamics of Small-Particle Suspensions using Meso-Scale Modeling . [Thesis]. Kyoto University; 2009. Available from: http://hdl.handle.net/2433/77956

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

25. NGUYEN HOANG HUY. Periodic Fibre Suspension in a Viscoelastic Fluid - A Simulation by a Boundery Element Method.

Degree: 2008, National University of Singapore

URL: https://scholarbank.nus.edu.sg/handle/10635/28293

Subjects/Keywords: Fibre suspension; Shear flow; Viscoelastic matrix; Periodic; Viscosity; CDLBEM

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APA (6^th Edition):

HUY, N. H. (2008). Periodic Fibre Suspension in a Viscoelastic Fluid - A Simulation by a Boundery Element Method. (Thesis). National University of Singapore. Retrieved from https://scholarbank.nus.edu.sg/handle/10635/28293

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):

HUY, NGUYEN HOANG. “Periodic Fibre Suspension in a Viscoelastic Fluid - A Simulation by a Boundery Element Method.” 2008. Thesis, National University of Singapore. Accessed April 12, 2021. https://scholarbank.nus.edu.sg/handle/10635/28293.

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

MLA Handbook (7^th Edition):

HUY, NGUYEN HOANG. “Periodic Fibre Suspension in a Viscoelastic Fluid - A Simulation by a Boundery Element Method.” 2008. Web. 12 Apr 2021.

Vancouver:

HUY NH. Periodic Fibre Suspension in a Viscoelastic Fluid - A Simulation by a Boundery Element Method. [Internet] [Thesis]. National University of Singapore; 2008. [cited 2021 Apr 12]. Available from: https://scholarbank.nus.edu.sg/handle/10635/28293.

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

Council of Science Editors:

HUY NH. Periodic Fibre Suspension in a Viscoelastic Fluid - A Simulation by a Boundery Element Method. [Thesis]. National University of Singapore; 2008. Available from: https://scholarbank.nus.edu.sg/handle/10635/28293

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

26. Loisy, Aurore. Direct numerical simulation of bubbly flows : coupling with scalar transport and turbulence : Simulation numérique directe d’écoulements à bulles : couplage avec le transport de scalaire et la turbulence.

Degree: Docteur es, Mécanique des Fluides, 2016, Lyon

URL: http://www.theses.fr/2016LYSE1142

►

Cette thèse est consacrée aux écoulements homogènes de bulles, ainsi qu'à leur couplage avec le transport d'un scalaire et la turbulence. Elle s'intéresse plus spécifiquement… (more)

▼

Cette thèse est consacrée aux écoulements homogènes de bulles, ainsi qu'à leur couplage avec le transport d'un scalaire et la turbulence. Elle s'intéresse plus spécifiquement aux effets de taille finie, des interactions hydrodynamiques et de la microstructure de la suspension qui sont étudiés à l'aide de simulations numériques directes à l'échelle d'une seule bulle. La dynamique d'une suspension laminaire de bulles induite par la seule gravité est d'abord revisitée. L'influence de la fraction volumique sur la vitesse de dérive des bulles est établie analytiquement et numériquement pour une suspension parfaitement ordonnée, puis des ressemblances entre suspensions ordonnées et suspensions désordonnées sont mises en évidence. Ces résultats sont ensuite mis à profit pour la modélisation du transport d'un scalaire passif au sein d'une suspension laminaire, tel que décrit par une diffusivité effective tensorielle, et des différences essentielles entre systèmes ordonnés et systèmes désordonnés concernant le transport de scalaire sont mises en exergue. Enfin, la turbulence est prise en compte dans les simulations et son interaction avec une bulle de taille finie est caractérisée. Il est montré que le comportement dynamique d'une bulle de taille comparable à la microéchelle de Taylor ressemble qualitativement à celui d'une microbulle, avec, notamment, une préférence pour certaines régions caractéristiques de l'écoulement. Une définition de l'écoulement vu par la bulle compatible avec les modèles standards de masse ajoutée et de portance est finalement proposée

This thesis is devoted to the study of homogeneous bubbly flows and their coupling with scalar transport and turbulence. It focuses on the effects of finite size, hydrodynamic interactions, and suspension microstructure, which are investigated using direct numerical simulations at the bubble scale. The dynamics of laminar buoyancy-driven bubbly suspensions is first revisited. More specifically, the effect of volume fraction on the bubble drift velocity is clarified by connecting numerical results to theory for dilute ordered systems, and similarities between perfectly ordered and free disordered suspensions are evidenced. These results are then used for the modeling of passive scalar transport in laminar suspensions as described by an effective diffusivity tensor, and crucial differences between ordered and disordered systems with respect to scalar transport are highlighted. Lastly, turbulence is included in the simulations, and its interaction with a finite-size bubble is characterized. The behavior of a bubble as large as Taylor microscale is shown to share a number of common features with that of a microbubble, most notably, the flow sampled by the bubble is biased. A definition of the liquid flow seen by the bubble, as it enters in usual models for the added mass and the lift forces, is finally proposed

Advisors/Committee Members: Naso, Aurore (thesis director), Spelt, Peter (thesis director).

Subjects/Keywords: Écoulement à bulles; Dynamique de bulle; Suspension; Transport de scalaire; Diffusivité effective; Taille finie; Écoulement diphasique turbulent; Bubbly flow; Bubble dynamics; Suspension; Scalar transport; Effective diffusivity; Finite size; Turbulent multiphase flow; 532

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APA (6^th Edition):

Loisy, A. (2016). Direct numerical simulation of bubbly flows : coupling with scalar transport and turbulence : Simulation numérique directe d’écoulements à bulles : couplage avec le transport de scalaire et la turbulence. (Doctoral Dissertation). Lyon. Retrieved from http://www.theses.fr/2016LYSE1142

Chicago Manual of Style (16^th Edition):

Loisy, Aurore. “Direct numerical simulation of bubbly flows : coupling with scalar transport and turbulence : Simulation numérique directe d’écoulements à bulles : couplage avec le transport de scalaire et la turbulence.” 2016. Doctoral Dissertation, Lyon. Accessed April 12, 2021. http://www.theses.fr/2016LYSE1142.

MLA Handbook (7^th Edition):

Loisy, Aurore. “Direct numerical simulation of bubbly flows : coupling with scalar transport and turbulence : Simulation numérique directe d’écoulements à bulles : couplage avec le transport de scalaire et la turbulence.” 2016. Web. 12 Apr 2021.

Vancouver:

Loisy A. Direct numerical simulation of bubbly flows : coupling with scalar transport and turbulence : Simulation numérique directe d’écoulements à bulles : couplage avec le transport de scalaire et la turbulence. [Internet] [Doctoral dissertation]. Lyon; 2016. [cited 2021 Apr 12]. Available from: http://www.theses.fr/2016LYSE1142.

Council of Science Editors:

Loisy A. Direct numerical simulation of bubbly flows : coupling with scalar transport and turbulence : Simulation numérique directe d’écoulements à bulles : couplage avec le transport de scalaire et la turbulence. [Doctoral Dissertation]. Lyon; 2016. Available from: http://www.theses.fr/2016LYSE1142

27. Pham, Trung-Kien. Etude expérimentale et modélisation de la cristallisation d’hydrates de méthane en écoulement a partir d’une dispersion eau-huile a fort pourcentage d’eau : Experimental study and modelling on methane hydrates crystallization under flow from a water-oil dispersion at high water cut.

Degree: Docteur es, Génie des Procédés, 2018, Lyon

URL: http://www.theses.fr/2018LYSEM012

► La production de pétrole brut avec du gaz naturel et de l'eau à basse température et à haute pression favorise les conditions de formation d'hydrates… (more)

▼ La production de pétrole brut avec du gaz naturel et de l'eau à basse température et à haute pression favorise les conditions de formation d'hydrates de gaz qui peuvent causer de nombreux problèmes d’écoulement jusqu'au blocage des pipelines. Pour éviter le bouchage, diverses méthodes sont appliquées aux pipelines par addition d'inhibiteurs thermodynamiques (THIs), cinétiques (KHIs) et d'antiagglomérants (AAs). Récemment, l’utilisation des AAs est devenue plus courante car non seulement à cause de leur haute performance dans des conditions sévères, mais aussi grâce à la réduction du coût d’opération dû à avec une faible dose d’AAs utilisée (AA-LDHIs). La plupart des études antérieures sur la formation et transport d’hydrates de gaz se limitent à de faibles fractions d’eau et sans antiagglomérants. Pour des fortes fractions d’eau, la formation et le transport d'hydrates de gaz en présence d’AA-LDHI et/ou de sel dans les conduites d'écoulement restent mal compris. L'objectif principal de cette étude est une meilleure compréhension de la formation et de l’agglomération des hydrates, en testant l’influence des additifs commerciaux pour éviter le colmatage. Ce travail traite plus précisément de la cinétique de cristallisation et d'agglomération des hydrates, ainsi que du transport et du dépôt des suspensions en fonction des conditions d'écoulement (en particulier dans les systèmes à haute fraction d'eau). Les effets de divers paramètres sont étudiés, notamment : à faible dose d’antiagglomérant (AA-LDHI), et fraction volumique d'eau et de salinité dans l'eau variables dans un mélange avec du Kerdane®. Des expériences ont été menées dans la boucle "Archimède". Cet appareillage, capable de fonctionner à plus de 80 bar, permet de reproduire les conditions de transport de pétrole et de gaz dans les pipelines sous-marins. Il est équipé d'une sonde FBRM (Focused Beam Reflectance Measurement) et d'une sonde PVM (Particle Video Microscope) ainsi que de capteurs de température, de perte de charge, de débit et de masse volumique. La mise en circulation du fluide est assurée par une pompe Moineau et/ou un système dit de "gaz-lift". Les résultats ont révélé que dans le protocole avec gaz-lift, les hydrates se forment à la surface des bulles de gaz et des gouttelettes d'eau et leur transport a lieu dans les phases continues d'huile ou d'eau. Généralement, les hydrates ont tendance à se déposer à haute fraction d'eau et à s'agglomérer à une faible fraction d'eau. Des mécanismes de formation et transport des hydrates en présence de bulles ont été proposés. Dans le protocole avec pompe Moineau, les effets de la formation des hydrates, de l'agglomération, du dépôt et du colmatage dans le cadre d’un écoulement multiphasique et vice-versa ont été identifiés, analysés et évalués à fort pourcentage d’eau. Quelques mécanismes de formation et transport d'hydrates dans des conditions expérimentales différentes sont aussi proposés. Un modèle a été développé pour prédire la perte de charge relative dans les pipelines une fois l'hydrate… Advisors/Committee Members: Herri, Jean-Michel (thesis director).

Subjects/Keywords: Dispersion; Bulle de gaz; Ecoulement multiphasique; Formation d'hydrates de gaz; Agglomération; Déposition; Bouchage; Anti-agglomérants; Suspension; Transport de sorbets d’hydrate; Liquid-Liquid Dispersion; Gas bubble; Multiphase flow; Gas hydrate formation; Agglomeration; Deposition; Plug; Anti-agglomerants; Suspension; Hydrate slurry transport

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

APA (6^th Edition):

Pham, T. (2018). Etude expérimentale et modélisation de la cristallisation d’hydrates de méthane en écoulement a partir d’une dispersion eau-huile a fort pourcentage d’eau : Experimental study and modelling on methane hydrates crystallization under flow from a water-oil dispersion at high water cut. (Doctoral Dissertation). Lyon. Retrieved from http://www.theses.fr/2018LYSEM012

Chicago Manual of Style (16^th Edition):

Pham, Trung-Kien. “Etude expérimentale et modélisation de la cristallisation d’hydrates de méthane en écoulement a partir d’une dispersion eau-huile a fort pourcentage d’eau : Experimental study and modelling on methane hydrates crystallization under flow from a water-oil dispersion at high water cut.” 2018. Doctoral Dissertation, Lyon. Accessed April 12, 2021. http://www.theses.fr/2018LYSEM012.

MLA Handbook (7^th Edition):

Pham, Trung-Kien. “Etude expérimentale et modélisation de la cristallisation d’hydrates de méthane en écoulement a partir d’une dispersion eau-huile a fort pourcentage d’eau : Experimental study and modelling on methane hydrates crystallization under flow from a water-oil dispersion at high water cut.” 2018. Web. 12 Apr 2021.

Vancouver:

Pham T. Etude expérimentale et modélisation de la cristallisation d’hydrates de méthane en écoulement a partir d’une dispersion eau-huile a fort pourcentage d’eau : Experimental study and modelling on methane hydrates crystallization under flow from a water-oil dispersion at high water cut. [Internet] [Doctoral dissertation]. Lyon; 2018. [cited 2021 Apr 12]. Available from: http://www.theses.fr/2018LYSEM012.

Council of Science Editors:

Pham T. Etude expérimentale et modélisation de la cristallisation d’hydrates de méthane en écoulement a partir d’une dispersion eau-huile a fort pourcentage d’eau : Experimental study and modelling on methane hydrates crystallization under flow from a water-oil dispersion at high water cut. [Doctoral Dissertation]. Lyon; 2018. Available from: http://www.theses.fr/2018LYSEM012

28. Mecherbet, Amina. Modélisation des fluides multiphasiques : Modeling of multiphase flows.

Degree: Docteur es, Mathématiques et modélisation, 2019, Montpellier

URL: http://www.theses.fr/2019MONTS036

►

Dans cette thèse, nous nous intéressons à la modélisation et l'analyse mathématique de certains problèmes liés aux écoulements en suspension. Le premier chapitre concerne la… (more)

▼

Dans cette thèse, nous nous intéressons à la modélisation et l'analyse mathématique de certains problèmes liés aux écoulements en suspension. Le premier chapitre concerne la justification du modèle de type transport-Stokes pour la sédimentation de particules sphériques dans un fluide de Stokes où l'inertie des particules est négligée et leur rotation est prise en compte. Ce travail est une extension des résultats antérieurs pour un ensemble plus général de configurations de particules. Le deuxième chapitre concerne la sédimentation d'une distribution d'amas de paires de particules dans un fluide de Stokes. Le modèle dérivé est une équation de transport-Stokes décrivant l'évolution de la position et l'orientation des amas. Nous nous intéressons par la suite au cas où l'orientation des amas est initialement corrélée aux positions. Un résultat d'existence locale et d'unicité pour le modèle dérivé est présenté. Dans le troisième chapitre, nous nous intéressons à la dérivation d'un modèle de type fluide-cinétique pour l'évolution d'un aérosol dans les voies respiratoires. Ce modèle prend en compte la variation du rayon des particules et leur température due à l'échange d'humidité entre l'aérosol et l'air ambiant. Les équations décrivant le mouvement de l'aérosol est une équation de type Vlasov-Navier Stokes couplée avec des équations d'advection diffusion pour l'évolution de la température et la vapeur d'eau dans l'air ambiant. Le dernier chapitre traite de l'analyse mathématique de l'équation de transport-Stokes dérivée au premier chapitre. Nous présentons un résultat d'existence et d'unicité globale pour des densités initiales de type L¹∩L^∞ ayant un moment d'ordre un fini. Nous nous intéressons ensuite à des densités initiales de type fonction caractéristique d'une gouttelette et montrons un résultat d'existence locale et d'unicité d'une paramétrisation régulière de la surface de la gouttelette. Enfin, nous présentons des simulations numériques montrant l'aspect instable de la gouttelette.

This thesis is devoted to the modelling and mathematical analysis of some aspects of suspension flows.The first chapter concerns the justification of the transport-Stokes equation describing the sedimentation of spherical rigid particles in a Stokes flow where particles rotation is taken into account and inertia is neglected. This work is an extension of former results for a more general set of particles configurations.The second chapter is dedicated to the sedimentation of clusters of particle pairs in a Stokes flow. The derived model is a transport-Stokes equation describing the time evolution of the position and orientation of the cluster. We also investigate the case where the orientation of the cluster is initially correlated to its position. A local existence and uniqueness result for the limit model is provided.In the third chapter, we propose a coupled fluid-kinetic model taking into accountthe radius growth of aerosol particles due to humidity in the respiratory system. We aim to numerically investigate the impact of…

Advisors/Committee Members: Hillairet, Matthieu (thesis director).

Subjects/Keywords: Écoulements de fluides multiphasiques; Écoulements en suspension; Équations de Stokes; Navier Stokes; Vlasov; Système d'interactions de particules; Homogénéisation; Méthode de réflexions; Multiphase fluid flows; Suspension flow; Stoks; Navier Stokes; Vlasov equations; System of interacting particles; Homogenization; Method of reflections

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

APA (6^th Edition):

Mecherbet, A. (2019). Modélisation des fluides multiphasiques : Modeling of multiphase flows. (Doctoral Dissertation). Montpellier. Retrieved from http://www.theses.fr/2019MONTS036

Chicago Manual of Style (16^th Edition):

Mecherbet, Amina. “Modélisation des fluides multiphasiques : Modeling of multiphase flows.” 2019. Doctoral Dissertation, Montpellier. Accessed April 12, 2021. http://www.theses.fr/2019MONTS036.

MLA Handbook (7^th Edition):

Mecherbet, Amina. “Modélisation des fluides multiphasiques : Modeling of multiphase flows.” 2019. Web. 12 Apr 2021.

Vancouver:

Mecherbet A. Modélisation des fluides multiphasiques : Modeling of multiphase flows. [Internet] [Doctoral dissertation]. Montpellier; 2019. [cited 2021 Apr 12]. Available from: http://www.theses.fr/2019MONTS036.

Council of Science Editors:

Mecherbet A. Modélisation des fluides multiphasiques : Modeling of multiphase flows. [Doctoral Dissertation]. Montpellier; 2019. Available from: http://www.theses.fr/2019MONTS036

Florida International University

29. Xing, Keqiang. Numerical Investigation on the Heat Transfer Enhancement Using Micro/Nano Phase-Change Particulate Flow.

Degree: PhD, Mechanical Engineering, 2007, Florida International University

URL: https://digitalcommons.fiu.edu/etd/28 ; 10.25148/etd.FI08081550 ; FI08081550

► The introduction of phase change material fluid and nanofluid in micro-channel heat sink design can significantly increase the cooling capacity of the heat sink… (more)

▼ The introduction of phase change material fluid and nanofluid in micro-channel heat sink design can significantly increase the cooling capacity of the heat sink because of the unique features of these two kinds of fluids. To better assist the design of a high performance micro-channel heat sink using phase change fluid and nanofluid, the heat transfer enhancement mechanism behind the flow with such fluids must be completely understood. A detailed parametric study is conducted to further investigate the heat transfer enhancement of the phase change material particle suspension flow, by using the two-phase non-thermal-equilibrium model developed by Hao and Tao (2004). The parametric study is conducted under normal conditions with Reynolds numbers of Re=600-900 and phase change material particle concentrations ¡Ü0.25 , as well as extreme conditions of very low Reynolds numbers (Re < 50) and high phase change material particle concentration (0.5-0.7) slurry flow. By using the two newly-defined parameters, named effectiveness factor and performance index, respectively, it is found that there exists an optimal relation between the channel design parameters, particle volume fraction, Reynolds number, and the wall heat flux. The influence of the particle volume fraction, particle size, and the particle viscosity, to the phase change material suspension flow, are investigated and discussed. The model was validated by available experimental data. The conclusions will assist designers in making their decisions that relate to the design or selection of a micro-pump suitable for micro or mini scale heat transfer devices. To understand the heat transfer enhancement mechanism of the nanofluid flow from the particle level, the lattice Boltzmann method is used because of its mesoscopic feature and its many numerical advantages. By using a two-component lattice Boltzmann model, the heat transfer enhancement of the nanofluid is analyzed, through incorporating the different forces acting on the nanoparticles to the two-component lattice Boltzmann model. It is found that the nanofluid has better heat transfer enhancement at low Reynolds numbers, and the Brownian motion effect of the nanoparticles will be weakened by the increase of flow speed. Advisors/Committee Members: Yong X. Tao, Ali Ebadian, Michael Sukop, Yiding Cao.

Subjects/Keywords: suspension flow; numerical simulation; lattice Boltzmann method; phase change material; heat transfer

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APA (6^th Edition):

Xing, K. (2007). Numerical Investigation on the Heat Transfer Enhancement Using Micro/Nano Phase-Change Particulate Flow. (Doctoral Dissertation). Florida International University. Retrieved from https://digitalcommons.fiu.edu/etd/28 ; 10.25148/etd.FI08081550 ; FI08081550

Chicago Manual of Style (16^th Edition):

Xing, Keqiang. “Numerical Investigation on the Heat Transfer Enhancement Using Micro/Nano Phase-Change Particulate Flow.” 2007. Doctoral Dissertation, Florida International University. Accessed April 12, 2021. https://digitalcommons.fiu.edu/etd/28 ; 10.25148/etd.FI08081550 ; FI08081550.

MLA Handbook (7^th Edition):

Xing, Keqiang. “Numerical Investigation on the Heat Transfer Enhancement Using Micro/Nano Phase-Change Particulate Flow.” 2007. Web. 12 Apr 2021.

Vancouver:

Xing K. Numerical Investigation on the Heat Transfer Enhancement Using Micro/Nano Phase-Change Particulate Flow. [Internet] [Doctoral dissertation]. Florida International University; 2007. [cited 2021 Apr 12]. Available from: https://digitalcommons.fiu.edu/etd/28 ; 10.25148/etd.FI08081550 ; FI08081550.

Council of Science Editors:

Xing K. Numerical Investigation on the Heat Transfer Enhancement Using Micro/Nano Phase-Change Particulate Flow. [Doctoral Dissertation]. Florida International University; 2007. Available from: https://digitalcommons.fiu.edu/etd/28 ; 10.25148/etd.FI08081550 ; FI08081550

30. Gupta, Yashvardhan. Tools and Techniques for Flow Characterization in the Development of Load Leveling Valves for Heavy Truck Application.

Degree: MS, Mechanical Engineering, 2018, Virginia Tech

URL: http://hdl.handle.net/10919/95880

► This research examines different techniques and proposes a Computational Fluid Dynamics (CFD) model as a robust tool for flow characterization of load leveling valves. The… (more)

▼ This research examines different techniques and proposes a Computational Fluid Dynamics (CFD) model as a robust tool for flow characterization of load leveling valves. The load leveling valve is a critical component of an air suspension system since it manages air spring pressure, a key function that directly impacts vehicle dynamic performance in addition to maintaining a static ride height. Efficiency of operation of a load leveling valve is established by its flow characteristics, a metric useful in determining suitability of the valve for application in a truck-suspension configuration and for comparison among similar products. The disk-slot type load leveling valve was chosen as the subject of this study due to its popularity in the heavy truck industry. Three distinct methods are presented to model and evaluate flow characteristics of a disk-slot valve. First is a theoretical formulation based on gas dynamic behavior through an orifice; second is an experimental technique in which a full pneumatic apparatus is used to collect instantaneous pressure data to estimate air discharge; and third is a CFD approach. Significant discrepancies observed between theoretically estimated results and experimental data suggest that the theoretical model is incapable of accurately capturing losses that occur during air flow. These variations diminish as the magnitude of discharge coefficient is altered. A detailed CFD model is submitted as an effective tool for load leveling valve flow characterization/analysis. This model overcomes the deficiencies of the theoretical model and improves the accuracy of simulations. A 2-D axisymmetric approximation of the real fluid domain is analyzed for flow characteristics using a Realizable k-ϵ turbulence model, scalable wall functions, and a pressure-based coupled algorithm with a second order discretization function. The CFD-generated results were observed to be in agreement with the experimental findings. CFD is found to be advantageous in the evaluation of flow characteristics as it furnishes precise data without the need to experimentally evaluate a physical model/prototype of the valve, thereby benefitting suspension engineers involved in the development and testing of load leveling valve designs. This document concludes with a sample case study which uses CFD to characterize flow in a modified disk-slot load leveling valve, and discusses the results in light of application on a heavy truck. Advisors/Committee Members: Ahmadian, Mehdi (committeechair), Southward, Steve C. (committee member), Dancey, Clinton L. (committee member).

Subjects/Keywords: Pneumatic Suspension; Load Leveling Valve; Flow Rates; CFD

…suspension performance may be adjusted to a great degree by modifying flow characteristics of the… …as the ‘brain’ of the suspension system. Shortcomings related to available flow… …suspension systems would need more information than the given ‘standard’ and ‘low flow… …List of Figures Figure 2.1: Leaf suspension in application [4] (left)… …Air suspension in application (right) ........... 6 Figure 2.2: The rolling lobe…

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APA (6^th Edition):

Gupta, Y. (2018). Tools and Techniques for Flow Characterization in the Development of Load Leveling Valves for Heavy Truck Application. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/95880

Chicago Manual of Style (16^th Edition):

Gupta, Yashvardhan. “Tools and Techniques for Flow Characterization in the Development of Load Leveling Valves for Heavy Truck Application.” 2018. Masters Thesis, Virginia Tech. Accessed April 12, 2021. http://hdl.handle.net/10919/95880.

MLA Handbook (7^th Edition):

Gupta, Yashvardhan. “Tools and Techniques for Flow Characterization in the Development of Load Leveling Valves for Heavy Truck Application.” 2018. Web. 12 Apr 2021.

Vancouver:

Gupta Y. Tools and Techniques for Flow Characterization in the Development of Load Leveling Valves for Heavy Truck Application. [Internet] [Masters thesis]. Virginia Tech; 2018. [cited 2021 Apr 12]. Available from: http://hdl.handle.net/10919/95880.

Council of Science Editors:

Gupta Y. Tools and Techniques for Flow Characterization in the Development of Load Leveling Valves for Heavy Truck Application. [Masters Thesis]. Virginia Tech; 2018. Available from: http://hdl.handle.net/10919/95880

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