Matches in SemOpenAlex for { <https://semopenalex.org/work/W13136543> ?p ?o ?g. }
- W13136543 abstract "This thesis examines the behavior of a granular material sheared in a gap between two moving boundaries. In fluid mechanics, this type of flow is known as a Couette flow. Two different kinds of granular Couette flows were studied. First, gravity-free flow between two infinite plates moving in opposite directions was investigated using computer simulations. Second, flow between a stationary outer cylinder and an inner rotating cylinder was studied using both experiments and computer simulations. Two-dimensional discrete element computer simulations of infinite planar Couette flows were used to study the rheology, energy dissipation, and other flow properties in flows of particles of uniform size for three different gap widths. The energy dissipation rate was measured and a thermal analysis was conducted to determine the thermodynamic temperature rise and heat flux of such flows. Given a constant wall velocity, all of the properties in flows of identical particles were found to depend on the value of the solid fraction at the walls, which in turn depended on both the average solid fraction and the gap width. When the average solid fraction reached a critical threshold, the amount of work done on the flow drastically increased, increasing the average strain rate, granular temperature, wall stresses, and energy dissipation in the flow. This solid fraction threshold occurred after the center region of the flow had reached a dense limit and any further increase in solid fraction necessarily occurred in the wall regions. Various results from computer simulations were found to compare reasonably well with past results derived using kinetic theory. Mixing and other flow properties were also investigated in planar Couette flows of two different particle sizes, as functions of the size ratio and solid fraction ratio of the two species. Larger particles were found to migrate away from the regions of high fluctuation energy near the two moving boundaries in all cases. Mixture flows were found to behave very similarly to flows of mono-sized particles at high ratios of the solid fraction of small to large particles. As the solid fraction ratio decreased and the number of large particles increased, results deviated from the corresponding flow of identical particles. Flows with large size ratios of large to small particles deviated the most from the result of mono-sized particles, because stresses and energy dissipation rates are both mass-dependent. The second type of Couette flow, between two concentric cylinders, was investigated in a horizontal orientation (with the axis of rotation perpendicular to the direction of gravity) and in a vertical orientation (with the axis parallel to the direction of gravity), using both experiments and computer simulations. In the horizontal geometry, high-speed imaging was used to calculate experimental mean and fluctuation velocity profiles that were compared to results from three-dimensional discrete element simulations. Segregation of binary particle mixtures was also investigated in this geometry. Segregation in this flow was driven by a percolation mechanism acting at the free surface, causing large particles to migrate to the top. Computer simulations compared well qualitatively with experiments, successfully predicting the velocity profiles and the segregation pattern at the surface. When compared quantitatively, however, fluctuation velocities in the simulations were considerably greater than those found in the experiment, and the radial segregation observed in experiments did not occur to the same extent in simulations. The vertically-oriented cylindrical Couette flow experiment was used to measure the shear stress on the outer cylinder wall as a function of different variables. The shear stress was found to be independent of the inner cylinder rotation rate, because the material was unconfined and allowed to dilate. The measured stress showed a linear dependence on the height of material in the apparatus, indicating a hydrostatic variation of the normal stress. The shear stress also varied significantly with the ratio of the gap width to the particle diameter." @default.
- W13136543 created "2016-06-24" @default.
- W13136543 creator A5002362085 @default.
- W13136543 date "2000-01-01" @default.
- W13136543 modified "2023-09-27" @default.
- W13136543 title "Couette Flows of Granular Materials: Mixing, Rheology, and Energy Dissipation" @default.
- W13136543 cites W1557626936 @default.
- W13136543 cites W1805467683 @default.
- W13136543 cites W1806245062 @default.
- W13136543 cites W1964882024 @default.
- W13136543 cites W1968392349 @default.
- W13136543 cites W1974700774 @default.
- W13136543 cites W1975157966 @default.
- W13136543 cites W1976941482 @default.
- W13136543 cites W1978302446 @default.
- W13136543 cites W1978893684 @default.
- W13136543 cites W1981911509 @default.
- W13136543 cites W1983610158 @default.
- W13136543 cites W1984905125 @default.
- W13136543 cites W1997047776 @default.
- W13136543 cites W1998345867 @default.
- W13136543 cites W2000073819 @default.
- W13136543 cites W2003428588 @default.
- W13136543 cites W2010574799 @default.
- W13136543 cites W2022414003 @default.
- W13136543 cites W2040023088 @default.
- W13136543 cites W2042161232 @default.
- W13136543 cites W2057847617 @default.
- W13136543 cites W2058449088 @default.
- W13136543 cites W2063609027 @default.
- W13136543 cites W2066069204 @default.
- W13136543 cites W2067342084 @default.
- W13136543 cites W2069940971 @default.
- W13136543 cites W2073253688 @default.
- W13136543 cites W2077405903 @default.
- W13136543 cites W2077678598 @default.
- W13136543 cites W2080586142 @default.
- W13136543 cites W2082362994 @default.
- W13136543 cites W2082599901 @default.
- W13136543 cites W2086651394 @default.
- W13136543 cites W2091464788 @default.
- W13136543 cites W2093710737 @default.
- W13136543 cites W2099182564 @default.
- W13136543 cites W2139417932 @default.
- W13136543 cites W2144465675 @default.
- W13136543 cites W2146216970 @default.
- W13136543 cites W2155731760 @default.
- W13136543 cites W2155955559 @default.
- W13136543 cites W2158022963 @default.
- W13136543 cites W2316141598 @default.
- W13136543 cites W2568768589 @default.
- W13136543 cites W604554275 @default.
- W13136543 doi "https://doi.org/10.7907/hx15-pc72." @default.
- W13136543 hasPublicationYear "2000" @default.
- W13136543 type Work @default.
- W13136543 sameAs 13136543 @default.
- W13136543 citedByCount "0" @default.
- W13136543 crossrefType "dissertation" @default.
- W13136543 hasAuthorship W13136543A5002362085 @default.
- W13136543 hasConcept C121332964 @default.
- W13136543 hasConcept C135402231 @default.
- W13136543 hasConcept C159985019 @default.
- W13136543 hasConcept C18762648 @default.
- W13136543 hasConcept C192562407 @default.
- W13136543 hasConcept C200990466 @default.
- W13136543 hasConcept C203311528 @default.
- W13136543 hasConcept C2524010 @default.
- W13136543 hasConcept C2779099160 @default.
- W13136543 hasConcept C32568104 @default.
- W13136543 hasConcept C33923547 @default.
- W13136543 hasConcept C38349280 @default.
- W13136543 hasConcept C57879066 @default.
- W13136543 hasConcept C97355855 @default.
- W13136543 hasConceptScore W13136543C121332964 @default.
- W13136543 hasConceptScore W13136543C135402231 @default.
- W13136543 hasConceptScore W13136543C159985019 @default.
- W13136543 hasConceptScore W13136543C18762648 @default.
- W13136543 hasConceptScore W13136543C192562407 @default.
- W13136543 hasConceptScore W13136543C200990466 @default.
- W13136543 hasConceptScore W13136543C203311528 @default.
- W13136543 hasConceptScore W13136543C2524010 @default.
- W13136543 hasConceptScore W13136543C2779099160 @default.
- W13136543 hasConceptScore W13136543C32568104 @default.
- W13136543 hasConceptScore W13136543C33923547 @default.
- W13136543 hasConceptScore W13136543C38349280 @default.
- W13136543 hasConceptScore W13136543C57879066 @default.
- W13136543 hasConceptScore W13136543C97355855 @default.
- W13136543 hasLocation W131365431 @default.
- W13136543 hasOpenAccess W13136543 @default.
- W13136543 hasPrimaryLocation W131365431 @default.
- W13136543 hasRelatedWork W1514196545 @default.
- W13136543 hasRelatedWork W1554875196 @default.
- W13136543 hasRelatedWork W1988697198 @default.
- W13136543 hasRelatedWork W2007521675 @default.
- W13136543 hasRelatedWork W2031047234 @default.
- W13136543 hasRelatedWork W2037836704 @default.
- W13136543 hasRelatedWork W2039090577 @default.
- W13136543 hasRelatedWork W2063105189 @default.
- W13136543 hasRelatedWork W2069002176 @default.
- W13136543 hasRelatedWork W2145195595 @default.