Abstract：In order to identify effects of vane wrap angle on the cavitation induced vibration and noise of centrifugal pumps, a singlestage, endsuction centrifugal pump was chosen as the experimental model, in which the vane wrap angles were 110°, 115°, 120° and 125°, respectively, while the rest geometric parameter of the pump kept unchanged. The cavitation induced vibration and noise signals of the pump with different vane wrap angles were measured under various net positive suction heads available by using a closedloop centrifugal pump test rig, and then the signals were processed and analyzed. The experimental results showed that the vane wrap angle affects the pump cavitation performance without a clear regularity, but there exists an optimal angle indeed. With increasing wrap angle, the vibration intensities picked up at the four monitoring points don′t show a consistent pattern; however, the lowest intensity is founded at the discharge nozzle flange where all the intensity is below 1.0 m/s2. With increasing wrap angle, the peak values of noise signal at shaft rotating frequency decrease, but those at the blade passing frequency change in complicated manner under noncavitating condition. During both cavitation inception and development stage, the peak values of noise signal at the shaft rotating frequency always increase initially and then drop off. Furthermore, the peak values of the energy at 1 750-2 250 Hz also show the same pattern with exacerbation of cavitation.
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