Numerical prediction of cavitation erosion on a Francis turbine runner

The paper presents numerical prediction of cavitation erosion on a Francis turbine runner using CFD code. The kappa - omega SST turbulence model is employed in the Reynolds averaged Navier-Stokes equations in this study. A mixture assumption and a finite rate mass transfer model were introduced. The computing domain is discretized with a full three-dimensional mesh system of unstructured tetrahedral shapes. The finite volume method is used to solve the governing equations of the mixture model and the pressure-velocity coupling is handled via a Pressure Implicit with Splitting of Operators(PISO) procedure. Comparison the numerical prediction results with a real runner with cavitation damage, the region of higher volume fraction by simulation with the region of runner cavitation damage is consistent.