Isolated Airfoil-Tip Vortex Interaction Noise
Isolated Airfoil-Tip Vortex Interaction Noise
复制标题
隔离翼型叶尖涡相互作用噪声
DOI：
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发表时间：
1975
期刊：
影响因子：
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通讯作者：
C. Munch
中科院分区：
文献类型：
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作者：
R. Paterson;R. Amiet;C. Munch
在UARL声学研究风洞中进行了一项实验研究，以确定与静止叶尖涡和下游静止翼型相互作用相关的噪声特性。该模型试验几何形状以其最简单的形式模拟了悬停期间单旋翼直升机上发生的叶尖涡-桨叶相互作用。对于中到高升力试验条件，发现涡流-翼型相互作用会引起局部叶片失速，并伴随着叶片远场噪声的增加。这些结果表明，这种相互作用可能是直升机悬停时宽带噪声的一个重要来源。在表面安装和远场传声器之间进行的互相关测量表明，工作噪声机制是由失速产生的涡流与翼型后缘的相互作用引起的“后缘噪声”。在其他非旋翼应用中，这种机构预计会引起失速条件下噪声的增加。
An experimental investigation was conducted in the UARL Acoustic Research Tunnel to define the noise characteristics associated with the interaction of a stationary tip vortex and a downstream stationary airfoil. This model test geometry simulated, in its simplest form, the tip vortexblade interaction which occurs on single rotor helicopters during hover. For moderate to high lift test conditions, the vortex-airfoil interaction was found to cause local blade stall with an attendant increase in the blade far-field noise. These results indicated that this interaction may be an important source of helicopter broadband noise during hover. Cross-correlation measurements conducted amongst surface-mounted and far-field microphones demonstrated that the operative noise mechanism was "trailing edge noise" arising from the interaction of stall generated eddies with the airfoil trailing edge. This mechanism would be expected to be responsible for increased noise at stall conditions in other, nonrotary wing, applications.