Particle Clustering and Jetting in a Cylindrical Shock Tube

Professor Fue-Sang Lien

Abstract

It is widely observed in volcanic eruptions, supernovae and heterogeneous explosive detonation that expansion of condensed-phase particles forms clusters and coherent jets. Detonation of an explosive mixture containing densely-packed bulk liquid or solid particles provides a good approach in studying these dense particle flows inherently with particle clustering and jetting, which are generated at the very early stage of the particle dispersal process, persisting then for a long time. Despite progress to date in both experimental and numerical studies, the true mechanisms causing particle clustering and jetting are still unknown due to the complex phenomena involved in the early phase of expansion, including shock-particle interaction, particle collision and turbulence. In this talk, a cylindrical shock tube using a packed annular particle bed (also referred to as a "powder bed" herein) placed in the driven section with its far end adjacent to open air is numerically investigated, in order to understand the fundamental phenomena and physical mechanisms associated with the particle clustering and jet structures in the shock-compacting and expanding dense solid flow. Numerical simulations at mesoscale are performed over a range of parameters, including driver gas, particle morphology and distribution, and powder bed configuration

Biographic

Education

PhD, University of Manchester Institute of Science and Technology, UK, 1992, Mechanical Engineering

MASc, National Cheng Kung University, Taiwan, 1984, Mechanical Engineering

BASc, National Cheng Kung University, Taiwan, 1982, Mechanical Engineering

Research Interests

Computational Fluid Dynamics

Turbulence Modeling

Wind Engineering and Dispersion

Aerodynamics and Aeroacoustics

Teaching

Mechanical and Mechatronics Engineering at the University of Waterloo

Time: October 23,2013 10:30-11:30a.m.

Location: N-408 room,Mong Man Wai technology building

Host: Institute of Fluid Mechanics,School of Aerospace,Tsinghua University,Beijing 100084,P. R. China