A Concurrent Multiscale Framework Coupling Direct Simulation Monte Carlo and Molecular Dynamics

TL;DR

This paper introduces a novel multiscale coupling framework that integrates DSMC and MD simulations, enabling accurate and efficient modeling of complex flow phenomena across different scales.

Contribution

It generalizes previous coupling methods with a cell-based decision approach and provides operators for translating scales between DSMC and MD.

Findings

Framework verified on conservation laws

Demonstrated on hypersonic flow example

Discussed accuracy improvements over conventional DSMC

Abstract

We present a new method to couple the Direct Simulation Monte Carlo (DSMC) algorithm with molecular dynamics (MD). The coupling approach generalizes prior coupling methods using a cell-based decision. The approach is supported by a lifting and restricting operator, which translate length and time scales between DSMC and MD. We verify the framework on basic conservation laws, and demonstrate its usability on a hypersonic flow example. Its accuracy gain is discussed in light of conventional DSMC simulations. Advantages and limitations are discussed, and additional use cases are highlighted.