Comparison of the linear and non-linear SGS models in simulating the internal flow in a centrifugal pump impeller

摘要

In this paper, the performances of linear and non-linear SGS models are compared by simulating a centrifugal pump impeller at both design load and quarter load. The mesh convergence is studied to choose the mesh with 2.05 million. At design load, the flow behaves well in both channels and the two models perform similarly. While at quarter load, the "two-channel" flow pattern occurs. Although this phenomenon is detected by both models, the peak value of the velocity profile moves towards the pressure side, showing opposite tendency to PIV. Comparing the two models under this condition, DNM shows significant priority over DSM due to the improved relation between the SGS stress, the shear-stress and the vorticity.