Pressure gradient and friction factor for sedimentation and fluidisation of uniform spheres in liquids (original) (raw)
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RESUMEN DE TESIS PARA OPTAR AL GRADO DE DOCTOR EN CIENCIAS DE LA INGENIERÍA MENCIÓN FLUIDODINÁMICA POR: SERGIO PALMA M. PROF. GUÍA: CHRISTIAN IHLE B. Sedimentation of polydisperse particles at low Reynolds numbers in inclined geometries Numerical and laboratory experiments Hydraulic transport of particles at high concentrations in the industry is a widely used technique to deliver different sorts of granular materials by carrying them mixed with fluid, water in most cases. In the first chapter of this thesis, we will discuss the most important aspects of the dynamics of suspensions. In particular, we will explain the physics of dilute suspensions, semi dilute suspensions and concentrated suspensions. Additionally, a review of sedimentation of particles will be presented. Sedimentation is a process by which solid particles are separated from a fluid, usually under the action of gravitational forces. Sedimentation is one of the oldest known techniques used in industry to clean fluids ...
Canadian Journal of Chemical Engineering, 101, 210-216, 2023
The aims of this work are to elucidate the effects that bulk solids properties have on the effective drag experienced by large spheres immersed in an emulsion of group-B solids under minimum fluidization conditions and to analyze the ways in which the different suspensions react towards different applied shear rates. To investigate this, magnetic particle tracking was applied to resolve the trajectory of falling-sphere measurements in which the size, density, and sphericity of the bulk solids were varied as well as the size and density of the spherical tracers. The resulting experimental scope included both rising and sinking tracers as well as full segregation and in-bed stagnation of the tracers. The setup provided highly resolved tracer trajectories, from which the drag experienced by the sphere can be calculated. For sinking tracers, the results showed that an increase in bulk solids size, angularity, and density