偏航状态下空腔流动的数值模拟

摘要

采用基于S-A(Spalart Allmaras)湍流模型的脱体涡模拟方法(Detached-eddy simulation,DES),数值模拟研究了偏航状态下的空腔流动.首先,运用DES方法对非偏航状态下的空腔流动进行数值模拟,并和文献结果进行比较,验证该方法模拟空腔流动特性的能力;然后,运用DES方法数值研究偏航状态下的空腔流动,给出声压级的变化.数值研究表明:不同偏航角对空腔底部中心线处声压级产生很大的影响;与非偏航状态相比,在空腔底面中心线的某些位置处,给出了声压级随偏航角的变化规律为:声压级先是随着偏航角增加而缓慢增加,然后大大减小.%Based on detached-eddy simulation (DES),a flow past a yawed rectangular cavity is simulated numerically.An unyawed cavity flow is firstly simulated using the present DES method.Its effectiveness is further validated by a comparison of the calculated results with the results in references.Then simulations of low supersonic cavity flow at different yaw angles are carried out using DES,and the effect of yaw angles on sound pressure level (SPL) along the cavity floor is studied.Compared with the case of cavity flow at zero yaw angle,it is demonstrated that SPL gradually increases as yaw angle is enlarged,and then it sharply decreases at some certain test positions of cavity floor.