Periodic Boundary‐Layer Mesh Generation for Turbomachinery Using a Modified Bottom‐Up Approach

ABSTRACT Turbomachinery features complex geometry and flow‐field characteristics, which impose strict requirements on mesh generation. This study proposes a periodic boundary‐layer mesh generation scheme for turbomachinery. Semi‐structured prismatic mesh is widely used to resolve boundary‐layer flows in viscous flow simulations. However, ensuring the periodicity of the boundary‐layer mesh during the mesh generation process remains a challenging and underexplored problem. To address this issue, a feature recognition method based on periodic affine transformation is first developed. Using the resulting periodic transformation function, a bottom‐up periodic boundary‐layer mesh generation framework is developed, including periodic surface meshing, calculation of periodic marching directions and distances, invalid element removal, transition element correction, and compatible far‐field tetrahedral mesh generation. Validations on typical turbomachinery benchmarks, including NASA Stage 35, NASA C3X, and Rolls‐Royce ACE, show that the simulation results agree well with experimental data and results obtained using commercial software. These results verify the dependability of the developed approach and its practical value in turbomachinery analysis.