基于SNGR方法的二维增升装置噪声数值模拟

摘要

Noise of high lift device accounts for much in the airframe noise at approach period of airliners.What makes the noise of high lift device hard to predict is the complex geometrical conffiguration and the intricate flow structure.Apart from the means of experimental and theoretical methods, numerical simulation is also a important process to study aero-acoustics.On the basis of the Stochastic Noise Generation and Radiation(SNGR), obtain the time-averaged flow field first, then construct the acoustic source term by stochastic model, and finally solve the acoustic perturbation equation using high-accuracy and low-dispersion time and spatial schemes.A whole noise prediction system based on SNGR method is built, adopting two-dimension high lift device model 30P30N to simulate the acoustic propagation process, and analyzing the Sound Pressure Level frequency spectrum of monitor, thus realizing the fast noise prediction of 2D high lift device and laying foundation for the aerodynamic and acoustic integral design of 2D high lift device.%在大型客机起飞着陆阶段,增升装置噪声成为主要的机体噪声.由于增升装置特殊的气动外形及其与空气相互作用所形成的复杂流场结构,致使其噪声难以预测.除了试验和理论计算方法,数值模拟方法成为研究气动噪声的重要手段.依据随机噪声生成与传播(SNGR)方法的思路,先求解RANS方程得到时均流场解;然后运用随机模型构造声源项;最后采用高精度、低色散的时空格式离散求解非定常声扰动方程.基于SNGR方法建立的声场预测程序对二维增升装置30P30N的声场传播过程进行了模拟,分析了监测点的声压级频谱特性,实现了对声场的快速预测,为二维増升装置的气动、噪声一体化设计奠定了基础.