Sergey Averkin, Ph.D., a Research Scientist from Tech-X Corporation, gave a seminar Friday, February 28. He spoke about, “Kinetic Simulations of Non-equilibrium Phenomena in Partially Ionized Plasmas.”
Abstract: Partially ionized plasmas have many applications in science and engineering. The examples of applications include space propulsion, material processing including production of nanomaterials, ion sources, display panels, medicine. Modeling and simulation of non-equilibrium chemically reacting plasmas is a challenging problem owing to the presence of complicated plasma chemistry and coupling between volume, surface, and transport non-equilibrium processes. Simulation approaches span from volume averaged global models that incorporate thousands of chemical reactions and include simplified assumptions regarding transport to computationally expensive kinetic simulation methods that allow to calculate detailed information of plasma transport and usually employ simplified chemical models to speedup simulations.
The first part of the talk presents a Global Enhanced Vibrational Kinetic (GEVKM) model and its application to the simulation of an RF discharge chamber of a new High Current Negative Hydrogen Ion Source developed by Busek Co. Inc. and WPI. The GEVKM is supplemented by a comprehensive set of surface and volumetric chemical processes (22 species and more than 1000 chemical reactions) governing vibrational and ionization kinetics of hydrogen plasmas. The model is computationally efficient. It was used in parametric studies with thousands of points in parameter space.
The second part of the talk outlines new developments in the Particle-in-Cell and Direct Simulation Monte Carlo methods (PIC/DSMC) that are used to model partially ionized plasmas and rarefied gases that are described by kinetic equations coupled with the Poisson equation. The PIC/DSMC method can provide detailed information of the distribution functions of plasma components in complicated geometries. The applications of the PIC/DSMC method to simulations of flows inside nanonozzles and around CubeSat are presented. In addition, novel simulations of plasma assisted growth of nanoparticles using PIC/DSMC method are discussed.
Biography: Dr. Sergey N. Averkin received the B.S. and M.S. degrees in applied mathematics and physics from the Moscow Institute of Physics and Technology, Moscow, Russia, in 2007 and 2009, respectively, and the Ph.D. degree in aerospace engineering from the Worcester Polytechnic Institute (WPI), Worcester, MA, in 2015. From 2015 to 2016, he was a Post-Doctoral Fellow and an Adjunct Teaching Professor at WPI. In 2018 Dr. Averkin was a Research Associate at the University of Colorado Boulder. Currently he is a Research Scientist at the Tech-X Corporation, Boulder, CO, USA. His current research interests include advanced numerical simulations of nonequilibrium phenomena in chemically reacting rarefied gases and plasmas. Applications of such simulations include space propulsion, mass and heat transport at micro and nano scales, ion sources, plasma processing. Dr. Averkin is a member of the American Physical Society (APS) and the Institute of Electrical and Electronics Engineers (IEEE).