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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。
Cylinder-airfoil interference noise is mainly used to simulate a similar turbofan stator, or fan off the vortex to the rotor noise generated by the phenomenon. The shedding vortex of the cylinder flows with the air flow, impinging on the downstream airfoil, resulting in unsteady surface loads, resulting in strong noise. In the anechoic chamber with full anechoic chamber, the characteristics of cylinder-wing interference noise of three different sizes of cylinders were tested and simulated. The diameter of the cylinder is 10 mm, 15 mm and 20 mm respectively. The airfoil is NACA 0012 airfoil. The LES is used to calculate the flow field. The sound field calculation is based on the FW-H integral equation. The comparison of experiment and simulation shows that the cylindrical shedding vortex is a typical cyclonic Karman vortex street, and the interaction of airfoil is the main reason of noise generation. The Strouhal number of cylinder-wing interference pure noise of three different diameters Which is the same as that of Carmen vortex shedding vortex. The far field of noise is dipole directivity. As the cylinder size increases, the total sound pressure level of noise increases. The low frequency noise source is mainly located at the leading edge of the airfoil , High-frequency noise is mainly caused by the cylinder shedding vortex.