摘要
利用三维非结构N-S求解器,对长深比为5:1、宽深比为1:1的开式矩形空腔气动噪声进行了数值分析。采用Cubic k-ε湍流模型求解空腔流场并进行人工重构,结合非线性声学求解器(NLAS)预测空腔近场噪声特性。通过对比空腔底部声压级和功率谱密度的实验值与计算值,以及实验值、计算值、公式计算值和高精度格式值的谐振频率,验证上述计算方法的合理性。为抑制空腔噪声、改善空腔流场环境,采取3种修形结构,对比4种工况下空腔声压级、总声压级、Q准则下的涡等值面及Lamb矢量模云图,结果表明,尾缘斜面最有利于降低噪声,大约可降低5 dB。
A three-dimensional unstructured Navier-Stokes solver is employed for the numerical analysis of an open rectangular cavity with a length-to-depth(L/D)ratio of 5 and a width-to-depth(W/D)ratio of 1 on aerodynamic noise.Cubic k-εturbulence model is used to obtain turbulent flow field,conduct artificial reconstruction and predict the near-field cavity noise combining with nonlinear acoustic solver(NLAS).Numerical results are compared with experimental data of sound pressure level(SPL),power spectral density(DSP)along cavity floor,experimental data,calculated value,formula-calculated values and resonant frequency of high-order numerical schemes in order to verify the rationality of the above method.To suppress the cavity noise and improve the environment for cavity flow field,other three kinds of structure modification are taken.Cavity SPL,the overall SPL,vortex iso-surface under Q criterion and the nephogram of Lamb Vector under four conditions are compared and the result shows that the trailing edge slope most conducive to reduce noise by about 5 dB.
作者
马丽璇
李恩义
孙书霞
杨庆祥
MA Lixuan;LI Enyi;SUN Shuxia;YANG Qingxiang(Flight College,Anyang Institute of Technology,Anyang 455000,Henan,China)
出处
《中国民航大学学报》
CAS
2020年第5期10-16,共7页
Journal of Civil Aviation University of China
基金
安阳工学院校青年基金项目(QJJ2018025)。
关键词
气动噪声
非线性声学求解器
谐振频率
声压级
降噪
aerodynamic noise
nonlinear acoustic solver
resonance frequency
sound pressure level
noise reduction
