Hydraulic optimization design of centrifugal pumps aiming at low vibration noise

In order to reduce the vibration noise generated by the centrifugal pump in the working process and improve the working efficiency of the centrifugal pump, the sound field numerical calculation of IS80-65-160 single-stage single-suction centrifugal pump was carried out. Under the condition that the parameters of the pump body and the impeller remain unchanged, the number of blades of the prototype pump impeller was designed as 4, 5, 6, and 7, respectively. The flow-induced vibration and noise characteristics of centrifugal pumps were studied from two aspects of numerical simulation and test, and the renormalization group k-ε model was used to simulate the steady and unsteady state of centrifugal pumps with different blade numbers. The external characteristics, pressure pulsation characteristics, vibration, and noise of the centrifugal pump were obtained, and the flow-induced vibration and noise test platform of the centrifugal pump was built for experimental verification. The research showed that the flow induction in the model pump was the main factor affecting the vibration of the prototype pump, and the shaft frequency and blade frequency were the main reasons causing the noise of the prototype pump. The vibration of each blade was the most concentrated at onefold blade frequency, and the peak of the sound field acoustic pressure level of the pump body was higher than other frequencies at threefold blade frequency, which was most obvious in the tongue region of the volute. With the increase of blades, the noise in volute decreased. The vibration intensity of the 4-blade prototype pump was lower, but the efficiency and head were also lower. The vibration intensity of the 5-blade prototype pump was the highest, the comprehensive performance of the 6-blade prototype pump was better, and the vibration of the 7-blade prototype pump was unstable. The test results showed that six blades could effectively reduce the flow-induced vibration noise of centrifugal pumps and improve the working environment, which provided certain application value and guiding significance for the hydraulic design of the subsequent low-noise centrifugal pumps.