Lattice Boltzmann study of rarefied gas flows in curved geometries using the vielbein formalism

Abstract:

Rarefied gas flows, where nonequilibrium effects become important and the Navier-Stokes equations are no longer applicable, can be successfully described within the framework of the Boltzmann equation. A formulation of the Boltzmann equation with respect to general coordinates will be introduced. In order to keep the momentum space tied to the new coordinate frame, we employ an orthonormal vielbein field (i.e., a triad consisting of the noncommuting unit vectors of the coordinate frame) with respect to which the momentum space degrees of freedom are defined. The applicability of the proposed scheme is demonstrated by considering the circular Couette flow between coaxial cylinders, the flow in a gradually expanding channel, the heat transfer between coaxial cylinders and concentric spheres and the non-Cartesian shock wave propagation.

Bio:

Dr Busuioc is a Post Graduate Research Associate at the University of Edinburgh. He earned a PhD of Physics at the West University of Timisoara in January 2019, under the supervision of Dr. Victor Sofonea. During his PhD studies he worked on two main research projects involving Lattice Boltzmann models: one concerning liquid-vapour flows, managed by Dr. Victor Sofonea at the Romanian Academy, Timisoara Branch, and one concerning rarefied gas flows, managed by Dr. Victor E. Ambruş, at the West University of Timisoara.