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arXiv · 2601.10230

Volume penalization method for simulating flows around a rotating solid with multiple reference frame and sliding mesh

Ming Liu·Yosuke Hasegawa
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Abstract

Despite the significant role of turbomachinery in fluid-based energy transfer, precise simulation of rotating solid objects with complex geometry is a challenging task. In the present study, the volume penalization method (VPM) is combined with multiple reference frame (MRF) and sliding mesh (SLM), respectively, so as to develop immersed-boundary approaches for simulating flows around a rotating solid. The level-set function is adopted to represent arbitrary geometries embedded in Cartesian grids. The VPM body-forcing terms in the momentum equation are proposed for MRF and SLM, respectively, so as to build unified governing equations for both fluid and solid regions. The flows around a rotating cuboid under various rotating speeds are simulated by the present schemes, namely, VPM with MRF, and VPM with SLM, and compared to corresponding simulations by the body-fitted method (BFM). The results suggest the relative deviations of predicted pressure drop and torque between the present VPM and BFM are around 5%, demonstrating the validity of the present VPM.

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Ming Liu, Yosuke Hasegawa. 2026-01-15. Volume penalization method for simulating flows around a rotating solid with multiple reference frame and sliding mesh. https://doi.org/10.1016/j.compfluid.2026.107235

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