Adaptive Mesh Refinement for DDES Simulation on Transonic Compressor Cascade With Unstructured Mesh

There are local flow phenomena like shock wave/boundary interaction and tip leakage flow which strongly influence the compressor performance and stability. AMR (Adaptive Mesh Refinement) strategy shows attractive property for automatically refining local mesh and predicting higher local phenomenon details. This paper develops the AMR strategy for turbomachinery with unstructured mesh. Curved surface boundary matching is focused in AMR process for achieving high level simulation accuracy. The developed AMR strategy is used to improve shock wave prediction in this paper. Firstly two dimensional RANS simulation of compressor cascade L030-4 is conducted to test the AMR strategy. Refined mesh shows better shock wave details compared with the almost none shock wave structure of baseline mesh. Then quasi-3D DDES (Delayed Detached Eddy Simulation) simulation of this compressor cascade is conducted. Shock wave oscillation phenomenon is clearly shown for this cascade. Local mesh of shock wave oscillation region is automatically refined by AMR. The refined mesh predicts better shock wave details and better turbulence motion comparing to the baseline mesh.