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arXiv · 2506.05914

A Chimera method for high-fidelity simulation of turbulent flows

Andrea Di Mascio·Sergio Pirozzoli
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Abstract

We develop a block-structured solver for high-fidelity simulation of flows in complex geometries, based on overlapping (Chimera) meshes. The key components of the algorithm are a baseline dissipation-free central discretization and selective high-order filtering, which ensure uniform accuracy and minimal numerical diffusion. These favorable properties are preserved through efficient interpolation across overlapping blocks. Numerical tests demonstrate that the method guarantees a uniform order of accuracy even for distorted, overlapping meshes. Tests conducted for turbulent flow in a pipe show no significant issues at the interfaces or overlapping blocks, highlighting the method's potential for direct numerical simulation (DNS). Finally, we show that the method performs satisfactorily for geometrically complex problems, such as flow past a ship propeller, where it accurately replicates experimental data.

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Andrea Di Mascio, Sergio Pirozzoli. 2025-06-06. A Chimera method for high-fidelity simulation of turbulent flows. https://arxiv.org/abs/2506.05914

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