Numerical analysis of pressure fluctuation in the volute of centrifugal pump

In order to reveal the variation laws of the pressure fluctuation in the volute of a centrifugal pump,the three-dimensional unsteady flow fields in the centrifugal pump under three different conditions are numerically solved by means of the Reynolds-averaged Navier-Stokes method.The pressure fluctuations at different points of the same section of the volute and different points along the circumferential direction of the volute are analyzed.The results show that the pressure fluctuations in the volute are obvious.The dominant frequencies under three conditions are found to be the ones that the blades pass.The pressure fluctuations at the same section decrease first and then increase from the bottom to the rear of the volute,and high-frequency fluctuations at the monitoring points on the bottom of the volute are evident.Along the circumferential direction,with the increase of circular angles,the pressure fluctuations decrease.The amplitude of pressure fluctuations is the largest near the tongue where high-frequency fluctuations dramatically increase.