The problem of rod-airfoil interaction noise is a model for noise generation due to inflow or unstream turbulence interacting with a turbomachine bladerow or a wind turbine rotor.Wake from the rod convects with the flow,impinges of the airfoil to produce unsteady force,which acts as a sound source.This problem is investigated via simulation and experiment.The airfoil is NACA 0012,and the configuration is varied by changing the rod dimeter of the rod,which covers 10 mm,15 mm and 20 mm.Experiment is lanuched in an anechoic wind tunnel.Basing on the unsteady aerodynamic force of the rod and the airfoil,the far acoustics field is obtained by FW-H integral equations.From the research,getting some signficative conclusions.The Kármán wake of the rod impacts the airfoil in the down stream,producing periodic unsteady force,which induces the noise generated.The Strouhal number of the tone noise is 0.19,regardless of the rods' diameter.The noise of the far field has a dipole directivity,and the noise becomes more intense with incrase of the rod diameter.The low frequency noise sources are located around the leading adge of the airfoil,and the high frequency sources are located around the rod.%圆柱-翼型干涉噪声主要是用来模拟类似涡扇静子,或者风机静子的脱落涡打到转子上所产生噪声的现象.圆柱的脱落涡随气流流动,对下游的翼型冲击,产生非定常表面载荷,带来强烈的噪声.在全消声室风洞,对三种不同尺寸圆柱的圆柱-翼型干涉噪声的特性进行了试验与仿真研究.圆柱的尺寸直径分别为10 mm、15 mm和20 mm,翼型为NACA 0012翼型;流场计算采用大涡模拟(LES),声场计算基于FW-H积分方程.对比实验与仿真可知,圆柱脱落涡是典型的周期性卡门涡街,翼面相互作用是产生噪声的主要原因;试验得到三种不同直径的圆柱-翼型干涉纯音噪声的斯特劳哈尔数为0.19左右,与卡门涡阶脱落涡的频率一致;噪声远场为偶极子指向性;随着圆柱尺寸的增大,噪声的总声压级增大;低频噪声源主要位于翼型前缘,高频噪声主要由圆柱脱落涡引起.
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