叶片出口边侧斜对船用离心泵振动和水动力噪声的影响

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

以125clla-13型船用离心泵为研究对象,研究叶片出口边侧斜对船用离心泵振动和水动力噪声的影响。首先对出口边非侧斜和侧斜两种叶轮模型泵进行全流场非定常数值计算,提取蜗壳及泄漏流道壁面脉动激励作为载荷,对两种模型泵进行基于模态响应的振动计算和基于边界元法的水动力噪声计算,并对非侧斜出口模型泵进行振动测试,经试验验证,模型泵振动噪声数值预测具有一定可行性。进一步对比两种出口方式模型泵计算结果,分析表明:叶片非侧斜出口模型泵振动加速度计算结果整体高于叶片侧斜出口;两种出口方式模型泵声功率随工况变化趋势一致,设计工况声功率最小,大流量工况声功率最大,叶片侧斜出口模型泵声功率和声压级都明显低于非侧斜出口,且声压级降幅从APF到4BPF大致呈上升趋势。从减振降噪角度考虑,叶片侧斜出口方式优于非侧斜出口方式。该研究可为船用离心泵减振降噪设计提供参考。

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.