|
|
Numerical analysis of unsteady cavitating flow characteristic in centrifugal pump |
School of Energy and Power Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China |
|
|
Abstract Based on full cavitation model and mixed two phase flow model, the steady and unsteady cavitating flow passages in centrifugal pump with specific speed of 130 were numerically simulated. The region and the degree of cavitation in the centrifugal pump flow passage were predicted.The characteristics of pressure fluctuation was achieved by monitoring the pressure fields around the volute tongue. The simulation results indicate that the cavitation generates at the suction side of blades near leading edge.The region of vapor extends and the volume fraction of vapor increases with the decreasing of total inlet pressure.The vapor appears on the pressure side of blades when the cavitation is deteriorated. The cavitation degree on each blade changes periodically with the change of relative position between impeller and volute. The frequency of pressure fluctuation shows obvious discrete characteristic with high blade passing frequency amplitude.With the development of cavitation degree, the pressure fluctuation amplitude induced by cavitating flow in flowpassage is increased with a corresponding relationship.
|
|
|
|
|
|
|
|