The flow field and sound field of trapezoidal rudder-wing under different rudder angles are numerically pre-dicted by CFD LES theory and Lighthill acoustic analogy theory, and characteristics of vorticity and flow noise are analyzed. Results show that: at the same speed, the vortex is more and more complex and the vorticity and flow noise increases with the increasing of rudder angle; vortex mainly concentrates in stabilizing wing leading edge, trailing edge of rudder-wing and between rudder and stabilizing wing; sound pressure level spectrum band of flow noise is wide and there is no obvious dom-inant frequency; at the low frequency, sound pressure level is higher, and continues to decline with the increasing of fre-quency; sound intensity at the front of leading edge and after trailing edge is higher than that at both sides of rudder-wing. This is also consistent with the results of flow field vorticity analysis, which shows that vortex is the root cause of flow noise.%以梯形舵翼结构为研究对象,采用CFD大涡模拟及Lighthill声类比理论对不同舵角下舵翼结构的流场和声场进行数值预报,分析其涡量特性及流噪声特性.结果表明:来流速度相同时,随着舵角的增大,涡系越来越复杂,涡量及流噪声也随之增大;涡系主要集中在稳定翼的导边、舵翼的尾缘及舵与稳定翼之间;舵翼结构流噪声的声压级频谱频带较宽,无明显的主频率出现;低频时声压级幅值较大,并且随着频率升高而持续下降;舵翼尾缘及稳定翼导边前缘的声场强度比翼型两侧的声场强度大,这也和流场涡量分析结果一致,进而说明了涡流是产生流噪声的根本原因.
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