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arXiv · 1609.00063

Mesh Resolution Effect on 3D RANS Turbomachinery Flow Simulations

Sergiy Yershov·Viktor Yakovlev
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Abstract

The paper presents the study of the effect of a mesh refinement on numerical results of 3D RANS computations of turbomachinery flows. The CFD solver F, which based on the second-order accurate ENO scheme, is used in this study. The simplified multigrid algorithm and local time stepping permit decreasing computational time. The flow computations are performed for a number of turbine and compressor cascades and stages. In all flow cases, the successively refined meshes of H-type with an approximate orthogonalization near the solid walls were generated. The results obtained are compared in order to estimate their both mesh convergence and ability to resolve the transonic flow pattern. It is concluded that for thorough studying the fine phenomena of the 3D turbomachinery flows, it makes sense to use the computational meshes with the number of cells from several millions up to several hundred millions per a single turbomachinery blade channel, while for industrial computations, a mesh of about or less than one million cells per a single turbomachinery blade channel could be sufficient under certain conditions.

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Sergiy Yershov, Viktor Yakovlev. 2016-08-31. Mesh Resolution Effect on 3D RANS Turbomachinery Flow Simulations. https://arxiv.org/abs/1609.00063

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