摘要
利用流声耦合法对离心泵的水动力噪声进行数值模拟,研究汽蚀发展程度对水动力噪声的影响。流声耦合方法选择大涡模拟(Large Eddy Simulation,LES)和全空化模型对离心泵流场进行非定常计算,再以声学有限元混合方法(CFD/FEM)将流场信息转化为噪声信号。通过对比试验可知,模拟信号与实际信号吻合度较高,充分验证了方法的可行性。随后改变模拟条件,使汽蚀从无到严重发展,从而得到一系列流场云图和水动力噪声信号。结果表明,初生期汽蚀的形成过程可划分为3个阶段,各阶段的流场云图均存在较大差异,噪声频谱也有区别。汽蚀发展程度可以在水动力噪声频谱上得以体现,尤其在临界汽蚀余量点附近,噪声频谱趋势图存在明显特征。
The fluid-acoustic coupling method was used to simulate hydrodynamic noise of centrifugal pumps and to investigate cavitation effect on hydrodynamic noise,in which,the fluid-acoustic coupling method adopts LES（ large eddy simulation） and full-cavitation model to implement unsteady calculation in the pump flow field,and then employing CFD / FEM method to transform flow field information into the noise signal. The contrast test shows that the computational signals coincide better with experimental results and this proves the feasibility of this method. Changing simulation conditions and developing cavitations to get a series of flow maps and signals show that three stages can be seen in forming process of early cavitations which has different flow maps and noise signals; and the development of cavitations can be reflected in spectrums of the noise,especially near NPSH＇s critical point where the noise spectrum＇s trend chart has obvious features.
出处
《化工机械》
CAS
2016年第1期83-88,共6页
Chemical Engineering & Machinery
基金
吉林省科技发展计划项目(20130206008GX)
关键词
离心泵
汽蚀
水动力噪声
CFD
故障诊断
centrifugal pump
cavitation
hydrodynamic noise
CFD
fault diagnosis
