考虑飞机舱壁影响的螺旋桨声场时域预测法

通过引入镜像法,给出了一种能近似包含舱壁边界曲率影响的螺旋桨噪声时域预测法,其基本思想是把飞机舱壁当作无限长圆柱边界,在时域里求解该边界空间中的FW-H方程来预测螺旋桨辐射声场。数值计算结果表明,飞机舱壁对螺桨辐射声场有影响,且随舱壁曲率变化而变化,计及这些影响将有助于预测合理的舱壁表面螺桨辐射声场;另外,对螺桨飞机多个螺桨之间的干涉机制进行了一些初步的研究,计算结果表明,多桨之间的干涉严重,可以通过改变螺桨之间的相位差改变其干涉机制,以获得较低的舱壁表面噪声分布。

A TIME DOMAIN METHOD FOR PROPELLER NOISE PREDICTION INCLUDING AIRCRAFT FUSELAGE EFFECT

An approximate method which can include aircraft fuselage curvature effect on propeller noise is presented, based on solving the FW-H equation in time domain regarding the fuselage as an infinitely long cylinder. Numerical results show that propeller noise is affected by fuselage boundary and varies with the fuselage curvature, and also show that the interferences of different phase angles between multiple propellers result in different sound field distributions, on the fuselage, which implies that the optimum phase angles difference of multiple propellers could be chosen for noise reduction on the fuselage surface.