改变蜗壳宽度对离心风机气动噪声影响的数值计算与试验研究  

Numerical and Experimental Study on Effect of Volute Width on Aerodynamic Noise of a Centrifugal Fan

作　　者：刘晓良[1] 祁大同[1] 马健峰[1] 袁民建[1] 邱长安[1] 

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《西安交通大学学报》2008年第11期1429-1434,共6页Journal of Xi'an Jiaotong University

摘　　要：采用基于非定常流场的离心风机气动噪声源数值分析方法,定性分析了改变蜗壳宽度对T9-19No.6.3A离心风机偶极子声源强度的影响.数值计算表明:随着蜗壳宽度的增加,该风机主要的偶极子声源强度逐渐降低.以数值分析为指导,在改变蜗壳宽度的情况下对T9-19No.6.3A离心风机的气动性能和噪声特性进行了试验测量.试验结果表明:在整个变工况范围内,与原风机相比,随着蜗壳宽度的增加,风机的气动性能有所提高,风机的基频噪声有不同程度的降低,在高效点A声级降低了约3-5 dB,而涡流噪声有所增大,但在常用的大流量和中流量工况范围内,风机的噪声特性有所改善.A numerical analysis method was applied to investigate aerodynamic noise sources in an industrial centrifugal fan with forward swept blades and the increased volute width. In this method, a three-dimensional unsteady viscous flow in the centrifugal fan was calculated. The intensity of the dominant aerodynamic noise source was qualitatively obtained according to the static pressure change rate at the dominant field in the vicinity of the volute tongue. Numerical results show that increasing the volute width in a certain range can effectively lower the dipole-type discrete noise source level. Based on the numerical analysis, an experiment was conducted to study the influence of the volute width on the aerodynamic performance and the aerodynamic noise. The experiment results show that the numerical method applied in this work provides a good qualitative prediction of the noise change generated by the dipole source. With the increase of the volute width, the blade passing frequency levels of the modified fans decreased by about 3-5 dB（A） at the best efficiency point, while the broadband noise levels increased slightly. It seems that the overall noise characteristics and the aerodynamic performance can be improved.

关 键 词：离心风机 气动性能 气动噪声 蜗壳宽度 

分 类 号：O42[理学—声学] O35[理学—物理]