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arXiv · 2604.09984

Unified Gas-Kinetic Scheme for Unsteady Multiscale Flows with Moving Boundaries

Yue Zhang·Wenpei Long·Junzhe Cao·Kun Xu
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Abstract

Simulating multiscale flows with moving boundaries, such as hypersonic multi-body separation and flows in micro-electro-mechanical systems (MEMS), requires robust numerical methods that couple mesh deformation with complex flow physics. This paper presents a hybrid overlapping moving-mesh technique developed within the unified gas-kinetic scheme (UGKS). To mitigate the Courant-Friedrichs-Lewy (CFL) constraint, we extend the implicit unsteady UGKS solver to support moving meshes, incorporating memory-efficient data handling and parallel computing optimizations to maximize computational efficiency. Validated against hypersonic multi-body separation and thermal rarefied MEMS flows, the proposed scheme accurately resolves complex, dynamic multiscale phenomena. The results confirm that this robust and efficient method provides a highly reliable tool for modeling dynamic flow interactions in complex geometric configurations.

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Yue Zhang, Wenpei Long, Junzhe Cao, Kun Xu. 2026-04-11. Unified Gas-Kinetic Scheme for Unsteady Multiscale Flows with Moving Boundaries. https://arxiv.org/abs/2604.09984

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