Inelastic collisions and its influence on dynamic aspects of liquid-solid flow: an experimental and numerical study

Abstract

The energy dissipated during particle collisions in multiphase flows can significantly affect the fluid dynamic behavior of the phases in devices involving this kind of flow. Operational problems can result from not taking into account these collisions and their effects on other flow aspects, such as particle adhesion and changes in the drag and lift, in the equipment design. This project has the main objective of investigating the collisions of particles with different physical and mechanical properties and surface characteristics in viscous fluids, as well as to evaluate their influence on other fluid dynamic characteristics of the flow. For this purpose, this project proposes the construction of devices for the determination of the coefficient of restitution of particles colliding against different surfaces, and the lubrication force due to the interstitial fluid. Friction parameters will be estimated from the experimental measurements of the angle of repose and the angle of sliding friction. The drag and lift forces acting on the different particles and on particle clusters formed by them will be estimated from the terminal velocity experimental measurement. Computational Fluid Dynamics techniques and the Discrete Element Method will be used to simulate different phenomena present in the experiments. Simulation and experimental results will be compared and equations will be proposed to model the liquid flow of particles with different mechanical properties and surface characteristics. (AU)