报告题目：Fluid Forces and Heat Transfer in Non-Spherical Particle Assemblies using Particle Resolved Simulations
主讲人简介：Danesh Tafti is the William S. Cross Professor in the Department of Mechanical Engineering at Virginia Tech. He obtained his Ph.D. from the Mechanical Engineering Department at Penn State University in 1989. After two years of post-doctoral work he joined the National Center for Supercomputing Applications (NCSA) at the University of Illinois at Urbana-Champaign, where he held positions of Research Scientist, Senior Research Scientist, and Associate Director. He joined the Mechanical Engineering Department at Virginia Tech in 2002 where he directs the High Performance Computational Fluid-Thermal Science and Engineering Lab. In 2009, he was named the William S. Cross Professor of Engineering. He has served as the Chair of the departmental promotion and tenure committee from 2008-2012 and as the Interim Department Head from 2014 to 2015. His research interests are in high-end, multiscale, multiphysics simulations of single and multiphase systems in the broad areas of propulsion, energy and biological systems. He has over 220 peer reviewed publications to his credit and has given several invited, keynote, and plenary lectures at national and international conferences. He is a Fellow of ASME, Associate Editor of ASME J. Heat Transfer and editorial board member of the Int. J. Heat and Fluid Flow.
Gas-solid flows are fundamental to many industrial processes. Extensive experimental and numerical studies have been devoted to understand the interphase momentum and heat transfer in these systems. Most of the studies have focused on spherical particle shapes. However, in most natural and industrial processes, the particle shape is seldom spherical and the shape can have a significant impact on momentum, heat and mass transfer, which are fundamental to all processes. In this study particle-resolved simulations are performed to study momentum and heat transfer in flow through a fixed random assembly of ellipsoidal particles with sphericity
The incompressible Navier-Stokes equations are solved using the Immersed Boundary Method (IBM). A complete framework using particle-resolved simulations to study the assembly of particles with any shape is developed. The drag force of spherical and ellipsoidal particles is investigated. The lift force, lateral force and torque of ellipsoidal particles in assembly and their variations are quantitatively presented and it is shown that under certain conditions these forces and torques cannot be neglected as is commonly done. The heat transfer in assembly of ellipsoidal particle is also investigated, and a correlation is proposed.