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arXiv · 2303.16540

A Monte-Carlo ab-initio algorithm for the multiscale simulation of compressible multiphase flows

Marco Petrella·Remi Abgrall·Siddhartha Mishra
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Abstract

We propose a novel Monte-Carlo based ab-initio algorithm for directly computing the statistics for quantities of interest in an immiscible two-phase compressible flow. Our algorithm samples the underlying probability space and evolves these samples with a sharp interface front-tracking scheme. Consequently, statistical information is generated without resorting to any closure assumptions and information about the underlying microstructure is implicitly included. The proposed algorithm is tested on a suite of numerical experiments and we observe that the ab-initio procedure can simulate a variety of flow regimes robustly and converges with respect of refinement of number of samples as well as number of bubbles per volume. The results are also compared with a state-of-the-art discrete equation method to reveal the inherent limitations of existing macroscopic models.

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Marco Petrella, Remi Abgrall, Siddhartha Mishra. 2023-03-29. A Monte-Carlo ab-initio algorithm for the multiscale simulation of compressible multiphase flows. https://arxiv.org/abs/2303.16540

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