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DOE OSTI · 2441138

An improved stochastic weighted particle method for boundary driven flows

Hong, Andrew Y.K.·Gallis, Michael A.
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Abstract

Here, the stochastic weighted particle method (SWPM) is a generalization of the Direct Simulation Monte Carlo (DSMC) method where particle weights are variable and dynamic. SWPM is backed by a strong theoretical foundation but has not been critically evaluated for problems of practical interest. A thorough assessment of SWPM for boundary-driven flows reveals significant numerical artifacts near the boundary, notably a diverging heat flux. To correct the boundary heat flux, two modifications to SWPM are proposed: separated grouping and a spatially-dependent weight transfer function. To gauge the relative efficiency of SWPM in comparison to DSMC, a high-Mach-number wheel flow which forms a strong density gradient is also simulated.

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97 MATHEMATICS AND COMPUTINGDirect simulation Monte CarloRarefied gas dynamicsVariable weight particle methods

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BibTeXRIS

Hong, Andrew Y.K., Gallis, Michael A.. 2024-08-21. An improved stochastic weighted particle method for boundary driven flows. https://doi.org/10.1016/j.jcp.2024.113353

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