基于FW-H方程的飞机低速构型气动噪声计算

Aero-Acoustic Calculation of Aircraft High-Lift Device Based on FW-H Equation

由流体力学Navier-Stokes方程导出的非齐次波动方程———Ffowcs Williams-Hawkings方程(以下简称FW-H方程),可以精确描述在静止流体中运动物体与流体相互作用的发声问题.以FW-H方程为理论依据,采用混合方法:近场声源区采用CFD求解,获得流场信息;远场声传播区采用自主开发的声场计算程序求解三维FW-H方程时域解,计算得到观察点频谱图和总体声压级.

Ffowcs Williams-Hawkings equation, the non-homogeneous wave equation derived from Navier-Stokes equations, can accurately describe noise generated from moving body interactive with fluid. With FW-H equation as the theory basis, hybrid method is used to calculate aero-acoustics： in the near field which is the sound source area, CFD computation is used to obtain flow field variables; in the far field, according to sound analogy method, self-developed acoustics code is used to calculate sound propagation by three-dimensional FW-H frequency-domain solutions. Finally, the SPL（SOund Pressure Level） spectrum and the OASPL（Overalt Sound Pressure Level） of the observation points can be obtained.