双级滑阀式真空泵排气系统结构噪声预测  

Simulation of Exhaust Noiseof Two-Stage Rotary Piston Vacuum Pump

作　　者：于振华[1] 李志远[1] 姜康[1] 

机构地区：[1]合肥工业大学机械与汽车工程学院,合肥230009

出　　处：《真空科学与技术学报》2014年第8期787-792,共6页Chinese Journal of Vacuum Science and Technology

摘　　要：基于大涡模拟和声学类比理论相结合的方法对双级滑阀式真空泵排气系统结构噪声进行预测,根据预测结果分析噪声分布规律及气动噪声声场特性。通过CFD数值模拟计算,对排气系统结构管道不同截面测量点的压力进行了频谱分析,对比了不同监测点声压的特点。通过数值模拟计算,预测值和试验数据良好吻合。结果表明,变截面结构的排气系统的主要噪声源来自于排气腔近出口处,变截面处也是气动噪声的来源,排气腔声场具有对称性;双级滑阀泵排气系统气动噪声能量主要集中在1000 Hz以内,在低频时具有偶极子特性的辐射指向性,高频宽带噪声不具有指向性。The noise, originated from the exhaust of two-stage rotary piston vacuum pump, was physically simplified, mathematically modeled in method of large eddy simulation （LED） and acoustic analogy, numerically simulated with computational fluid dynamics software CFD, and experimentally investigated. The sound pressure level spectra were monitored at the major sampling spots of the exhaust, where changes in cross-sectional area ocur. The simulatedresults were found to agree well with the measured data. The aerodynamic noise, with narrow peak centered at 1000 Hz, mainly comes from around the outlet of the exhausting cavity with a symmetric sound field and the spots where abrupt change in cross-sec- tional area occurs. In low frequency range, the radiation directivity of the aerodynamic noise resembles that of a dipole source, whereas in high frequency range, no distinct radiation directivity was identified.

关 键 词：噪声预测 大涡模拟 排气系统 滑阀真空泵 

分 类 号：TB535.2[理学—物理]