飞机螺旋桨噪声的数值计算

介绍一种螺旋桨厚度噪声和载荷噪声声压时间历程的计算方法。本方法是基于对FW-H方程的准确求解,并限制螺旋桨叶尖相对速度为亚音速。螺旋桨几何参数以及观察点位置等在三个坐标系中描述,应用Newton迭代法求解延迟时间方程,表面积分是应用标准三次样条函数计算,最后应用标准FFT程序计算噪声的频谱。通过实例计算发明本文方法计算的时域和频域结果均令人满意。

THE NUMERICAL CALCULATION OF AIRCRAFT PROPELLER NOISE

A method for calculating the acoustic pressure of a propeller due to blade thickness and steady surface pressure loading (including the effect of forward motion) is presented in this paper. The blade tip speed is limited to subsonic. The formulation is based on the FW-H equation. The blade parameters and observer position are described in three coordinates. The retarded time equation is solved numerically by Newton's method. The surface integration is calculated by a cubic spline program. Noise frequency spectrum is analysed by used a FFT program.A good agreement is found between theoretical and experimental results within both the time and frequency domains.