Turbulent mixing induced by shock-driven instabilities

Ricardo Mejia-Alvarez, Assistant Professor, Department of Mechanical Engineering, Michigan State University

Thursday, March 30, 2017
1:30 p.m.
Hopeman 224

A Richtmyer-Meshkov Instability (RMI) occurs when a shock wave interacts with a spatially perturbed interface between two fluids of different density. The subsequent growth of this instability typically results in turbulent mixing of species. RMIs are known to take place from large-scale processes like supernovae, to microscopic scales like inertial confinement fusion (ICF). A deep understanding of the physical phenomena behind RMI is critical, either to understand the consequences behind the natural events in which it is present, or to attempt to control its effects in technological applications. In this talk, I will discuss some fundamentals of this phenomenon as well as some experimental results.

Bio:

Ricardo Mejia-Alvarez obtained a B.S. degree in Mechanical Engineering from The National University of Colombia in 2000 and a M.Sc. degree in Thermal Engineering in 2004 from the University of Antioquia (at Medellin - Colombia). The same year, he obtained a Fulbright fellowship to pursue PhD studies in the University of Illinois at Urbana-Champaign, where he obtained a M.Sc. and a Ph.D. degree in Theoretical and Applied Mechanics. For his work on turbulent boundary layers over highly irregular rough surfaces, the American Physical Society awarded Dr. Mejia-Alvarez the 2011 version of the Francois Frenkiel Award for Fluid Dynamics. After concluding his Ph.D. program, he joined the Physics Division at Los Alamos National Laboratory (LANL) as a Postdoctoral Research Associate to develop a novel facility to study shock-driven instabilities. Ricardo became a Staff Scientist at LANL in 2013 to continue his work on topics relevant to supernova explosions, inertial confinement fusion and stockpile stewardship. In August 2016, he joined the Department of Mechanical Engineering at Michigan State University as an Assistant Professor.