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arXiv · 2506.01924

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

Tim Linke·Dane Sterbentz·Niels Grønbech-Jensen·Jean-Pierre Delplanque·Jonathan Belof
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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.

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Tim Linke, Dane Sterbentz, Niels Grønbech-Jensen, Jean-Pierre Delplanque, Jonathan Belof. 2025-06-02. A Concurrent Multiscale Framework Coupling Direct Simulation Monte Carlo and Molecular Dynamics. https://arxiv.org/abs/2506.01924

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