%A Wang Hongguang,Xu Xiaolong,Yang Ailing,Wang Fenghua,Tan Yongxue %T Numerical simulation of flow noise in axial- flow pump %0 Journal Article %D 2011 %J Journal of Drainage and Irrigation Machinery Engin %R 10.3969£¯j.issn.1674¡ª8530.2011.03.004 %P 199-203 %V 29 %N 3 %U {http://zzs.ujs.edu.cn/pgjx/CN/abstract/article_179.shtml} %8 2011-05-30 %X In order to research the rules and relationship between internal pressure pulsation and flow noise under different conditions,flow field and acoustic field of an axial-flow pump were simulated by computational fluid dynamics software Fluent and acoustic software LMS Virtual Lab numerically,and then both time and frequency domain analysis were applied.Taking the unsteady fluctuating pressure exerted by the fluid on the blade as noise source,BEM was applied to compare the difference of pump casing boundary acoustic field distributions between the condition of acoustic-only and acoustic-vibration coupling.The results show that static pressure pulsation in each checkpoint on impeller blades,guide vane blades and interfaces between rotating blades and the stationary blades show obviously discrete spectrum characteristics in spectrum diagrams,and the blade passing frequency is the dominate contents of both the pressure fluctuations and flow noise data,which manifests that the fluid-structure interaction between the rotating blades and the stationary ones may be the primary disturbance source.The flow noise frequency spectra has obvious peak at the double harmonic frequency and the triple harmonic frequency.Neglecting the pump casing vibration influence,the sound level is too high,while it is closer to practice with considering that influence.Therefore,structure vibration is very important in analyzing the noise radiation level.Noise directionality distribution chart indicates that blade noise radiation has obvious dipole characteristics.