中文摘要：

在台架上测试了旋涡风机噪声特性,并利用CFD和有限元法计算了旋涡风机内部流场及其远场气动噪声.首先通过离散涡模拟计算了旋涡风机内部的非定常流动,通过涡量和声功率云图得知其主要噪声源为流道内前半部分流场;通过监测流场内压力波动得知,流场内压力脉动频谱基本反映远场噪声的频谱;然后建立其气动声学计算模型进行有限元分析,结果表明,气动声学的有限元计算与试验数据比较吻合,而用格林函数积分解法所做的简化导致结果有较大的误差;最后通过各场点声压级得出各平面的噪声指向性,为旋涡风机整车布置及其降噪提供一定的依据.

英文摘要：

A bench test on the noise characteristics of regenerative flow compressor is conducted and both CFD and FEM are used to calculate the internal flow field of the compressor and its far-field aerodynamic noise. The unsteady flow inside the compressor is calculated first by using discrete eddy simulation, and it is found from the nephograms of vorticity and sound power that the major noise source is the front half flow field. The monitoring on the pressure fluctuation in flow field indicates that the spectra of the pressure fluctuation basically reflect the spectra of far-field noise. Then an aeroacoustic FE model is built with a finite element analysis performed. The results show that the finite element calculation of aeroacoustics matches well with test data, while the simplification made in the integral solution of Green＇s function leads to larger errors. Finally, the noise directivities in different planes are ob- tained based on the sound pressure level at field points, providing some basis for the layout of compressor in vehicle and its noise reduction.