采用附加导叶的轴流式风机气动噪声研究

An Investigation on the Aerodynamic Noise in the Axial Flow Fan with Additional Guide Vanes

在分析轴流式风机噪声源及其理论模型的基础上，应用叶轮机械叶片内部绕流控制的气动理论与边界层理论，提出了设置在工作轮叶尖与沿叶高上、中、下后缘处的附加导叶装置，以控制叶尖间隙噪声与沿叶高出口尾迹涡流噪声．采用油膜法进行了内部流场显示，对比试验研究表明，采用这种附加导叶的轴流式风机，其气动噪声有明显的降低，同时，改善了沿叶面的流速分布，提高了风机效率．

Based on an analvsis of the aerodvnamicnoise source and its theoretical moddf of thelow pressure axial flow fan,and with the theory of the boundary layer and the aerodynamictheory of peripheral control inside the turbomachine blade,a new peripheral control methodwith additional guide vanes fitted on the blade surface is preposed.With these guide vanes,the stream momentum in the boundary layer is found to be larger and the velocity distribu-tion on the blade surfaces as well as the fan efficiency are improved;Contrast experimentalresults show that the noise level is reduced by 2 to 5 dB(A)when the guide vanes are parallelto the direction of the airstream on the blade surface.