Numerical Simulation of A Cavitating Centrifugal Pump

Current study is related with numerical simulation of a centrifugal pump impeller with the specific speed of nq=13. By the help of computational fluid dynamics (CFD) at different operating points, pump performance rsults (Head-Discharge graph) are obtained. Simulations were in good agreement with experimental results. Afterwards, two phase CFD study is carried out in order to examine the cavitation performance of the pump. According to the numerical cavitation tests conducted in selected flow rates by decreasing the inlet pressure gradually; required net positive suction (NPSHR) curve of the pump is obtained. During meshing procedure, single blade passage is considered and tetrahedrons are used. On the other hand, while meshing the vaneless diffuser, hexahedron elements are used. Finer grids are adopted on solid surfaces for a detailed flow observation. Shear Stress Transport (SST) turbulence model is used throughout the study and Rayleigh-Plesset cavitation model is applied in two phase simulations.