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DOE OSTI · 1601261

A velocity space hybridization-based Boltzmann equation solver

Oblapenko, George·Goldstein, David·Varghese, Philip·Moore, Christopher Hudson
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Abstract

In the present research, a new method for simulation of rarefied gas flows is proposed, a velocity-space hybrid of both a DSMC representation of particles and a discrete velocity quasi-particle representation of the distribution function. The hybridization scheme is discussed in detail, and is numerically verified for two test-cases: the BKW relaxation problem and a stationary Maxwellian distribution. It is demonstrated that such a velocity-space hybridization can provide computational benefits when compared to a pure discrete velocity method or pure DSMC approach, while retaining some of the more attractive properties of discrete velocity methods. Further possible improvements to the velocity-space hybrid approach are discussed.

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97 MATHEMATICS AND COMPUTINGBoltzmann equationDirect simulation Monte CarloDiscrete velocity methodRarefied gas dynamics

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Oblapenko, George, Goldstein, David, Varghese, Philip, Moore, Christopher Hudson. 2020-02-03. A velocity space hybridization-based Boltzmann equation solver. https://doi.org/10.1016/j.jcp.2020.109302

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