Speaker: Evan Habbershaw, UTK

Title: Multi-Species Kinetic Models with Temperature Dependent Collision Frequencies

Abstract:

The multi-species Boltzmann equation--a fundamental model for gas and plasma mixtures--is computationally expensive due to its high-dimensional phase space and collision integrals.  In this talk, we will examine kinetic models that approximate the multi-species Boltzmann collision operator and incorporate temperature-dependent collision frequencies, enabling more accurate simulation of dilute gas or plasma flow.  These models often require an implicit treatment of the collision operator to overcome restrictive CFL-type conditions.  We will discuss fundamental properties of these kinetic models, develop an implicit numerical method to efficiently compute the collision update, and numerically demonstrate the system's dynamics using the method within a semi-implicit (IMEX) Runge-Kutta framework.