Effect of inclined trailing edge of blade on vibration and hydrodynamic noise of marine centrifugal pump

In order to analyze the effect of inclined trailing edge of blade on the vibration and hydrodynamic noise of marine centrifugal pump, 125clla-13 type marine centrifugal pump was chosen as a research object. A blade with inclined trailing edge and a blade without inclined trailing edge were used in the unsteady numerical simulation of the pump's whole flow passage respectively. The pressure fluctuations on the walls of volute and leakage flow passage were calculated and then used as the vibration source and dipole source to calculate the vibration with the modal response method and the hydrodynamic noise with the BEM. A vibration experiment on the pump without inclined trailing edge was also carried out and it verifies that the simulation of NVH is of certain feasibility. The simulation results with respeet to the two blade styles were analysed and show that the vibration acceleration of the blade with inclined trailing edge is less than that of the other one on the whole, the changing trends of the sound powers of the two blade styles along with the working conditions are consistent, the minimum of sound power is in the design condition, and the maximum is in the larger flow condition. Both the sound power and the sound pressure level (SPL) of the blade with inclined trailing edge are obviously less than those of the other one, and the decreasing extent of the SPL is generally rising from APF to 4BPF. Considering the terms of vibration and noise reduction, the blade with inclined trailing edge is superior to the blade without inclined trailing edge. The research results are useful for the vibration and noise reduction design of marine centrifugal pumps. ©, 2015, Chinese Vibration Engineering Society. All right reserved.