Coupling of particle-based and grid-based methods within object-oriented multi-physics CFD framework

Abstract

A novel multi-physics approach involving mesh-based methods for kinetic-Boltzmann equations coupled with molecular dynamics (MD) simulations of thermal relaxation is introduced. The particle method, its parallel performance and the implemen- tation in MΦC are discussed, including the unification and re-use of the source code for different methods and models. The hypersonic partially rarefied flow of a diatomic gas around a sphere and a spaceplane configuration are considered as examples, providing de- tails about the thermal non-equilibrium conditions to be modelled using MD simulations. The MD results show that existing empirical models may not provide sufficient accuracy for the gas flow in strong expansions and that the proposed method provides a mechanism for improving the accuracy.