一种新型离心风机的气动噪声数值仿真

以一种新型离心风机为例，运用Lighthill声比拟理论和计算流体动力学技术对离心风机的非定常流场和气动噪声进行数值模拟。首先以风机内部静压脉动随时间的波动判断离心风机的主要噪声源的位置，然后，以噪声频谱图和1／3倍频程图分析离心风机的噪声组成，判断离心风机噪声的产生机理。并以实验结果作为根据，验证仿真结果的正确性。结果表明：在非定常流场中，离心风机的噪声源主要分布在叶片与蜗壳之间的狭窄区域，在气动噪声成分中涡流噪声所占的比例最大，其产生的主要原因是由于叶片尾缘漩涡脱落造成的压力脉动形成的。

A new aerodynamic noise centrifugal fan numerical simulation

The research object is a new type of centrifugal fan, the unsteady flow field and aerodynamic noise centrifugal fan for numerical simulation is carried out using Lighthill acoustic analogy theory and computational fluid dynamics technology. Determining the location of rnain noise source of centrifugal fan is based on the static pressure impulse of the centrifugal fan, and then with analyzing the composition of the centrifugal fan noise with the noise spectrum and the 1/3 octave figure, judging the mechanism of centrifugal fan noise. With the experimental results prove the validity of the simulation. The results show that noise sources are mainly distributed in a narrow area between the blade and volute, and aerodynamic noise component in the vortex noise proportion is the largest.