Broadband shock-associated noise (BBSAN) is one dominant component from off-design supersonic jets. A time-domain BBSAN model is proposed and evaluated, which is based on the vector Green’s function solution of the decomposed Navier–Stokes equations. The source term is the scalar product of the anisotropic velocities with the mean pressure gradient. The approach uses large-eddy simulation (LES) databases. Proper orthogonal decomposition (POD) is applied to the scalar source field to extract the large-scale coherent structures associated with BBSAN. The key features of the BBSAN spectra are preserved when only a small fraction of POD modes are used to reconstruct the source field. The leading POD modes of the source term show strong amplification in the observer direction. Noise source contour plots calculated with these POD modes reveal that most noise sources are distributed at the shock-turbulence interactions. Predictions are validated with the Ffowcs Williams and Hawkings method and experimental data.

宽带震动相关噪声（BBSAN）是非设计型超音速喷气机的主要组成部分。提出并评估了时域BBSAN模型，该模型基于分解后的Navier–Stokes方程的矢量格林函数解。源项是各向异性速度与平均压力梯度的标量积。该方法使用大涡模拟（LES）数据库。将适当的正交分解（POD）应用于标量源字段，以提取与BBSAN相关的大规模相干结构。当仅使用一小部分POD模式来重建源场时，BBSAN光谱的关键特征得以保留。源项的领先POD模式在观察者方向上显示出强大的放大作用。用这些POD模式计算出的噪声源轮廓图表明，大多数噪声源是在冲击湍流相互作用下分布的。使用Ffowcs Williams和Hawkings方法以及实验数据验证了预测。