CAJ | 학술논문

方腔流动噪声问题因其流场变化复杂且剧烈而倍受关注，本文主要开展高亚声速方腔流动气动噪声数值预测方法研究。基于任意边界条件的格林函数解和 Lighthill 声模拟理论，提出可以考虑空间边界影响的气动噪声积分计算方法。数值模拟包含流动和噪声计算两部分，通过二阶精度的 DDES 模型进行流动数值模拟，边界积分方法计算散射声场分布。数值结果显示声场分布随时间呈现周期性变化，与流场的脉动及其脉动周期一致。观察点的声压级随频率逐渐下降且在谐波频率突然增大。本文计算结果与高精度计算气动声学方法计算结果相符，表明该方法合理、可靠，并且具有较高的计算效率。
방강류동조성문제인기류장변화복잡차극렬이배수관주，본문주요개전고아성속방강류동기동조성수치예측방법연구。기우임의변계조건적격림함수해화 Lighthill 성모의이론，제출가이고필공간변계영향적기동조성적분계산방법。수치모의포함류동화조성계산량부분，통과이계정도적 DDES 모형진행류동수치모의，변계적분방법계산산사성장분포。수치결과현시성장분포수시간정현주기성변화，여류장적맥동급기맥동주기일치。관찰점적성압급수빈솔축점하강차재해파빈솔돌연증대。본문계산결과여고정도계산기동성학방법계산결과상부，표명해방법합리、가고，병차구유교고적계산효솔。
The aerodynamic noise of cavity flow is a concern problem due to the complex and serious dynamic fluctuation,the goal of this paper is to study the numerical prediction method of aerodynamic noise generated by high subsonic cavity flow.With the help of Green′s function satisfied arbitrary boundary conditions and Lighthill′s Acoustic Analogy,the aeroacoustic integral computa-tional method taking into account the influence of physical boundary is presented.The numerical calculation includes two parts,flow and noise computations.The two-order DDES model is used to perform the fluid simulation while the present integral computational method calculates the distribution of scattering noise.Numerical results show that the distribution of noise field varies periodically,and it is in agreement with fluid fluctuation.The SPL gradually reduces with frequency and appears higher amplitudes at harmonic frequencies.Numerical results obtained with the present method agree well with that of high-order aeroacoustic computational method, which indicate that this method is valid and efficient to calculate high subsonic cavity noise.