Supersonic vehicles are subject not only to aerodynamic heating, but also to different acoustics, one of which is aeroacoustic induced by pressure fluctuation of high speed flow. The state-of-art structure sonic fatigue analysis is conducted by using uniformly distributed random White Gaussian Noise (WGN). However, uniformly distributed excitation is usually not consistent with the actual situation, and the validity of the method needs further investigation. In the present study, a nonlinear reduced-order model (NLROM) is presented to compute nonlinear response of isotropic and composite plates. The NLROM is based on finite element (FE) model and is constructed by means of Galerkin projection of the full order system onto a small subspace. The input of the NLROM is aerodynamic and aeroacoustic loads, which are computed by Large Eddy Simulation (LES) and interpolated from aerodynamic grid to structure node by using Radial Basis Function (RBF). The nonlinear response of the isotropic and composite plates is computed by NLROM and compared with WGN. The results show that the NLROM offers nearly an order of magnitude speed up as compared with direct FE simulation and predicts shorter sonic fatigue life than WGN.

超音速飞行器不仅受到气动加热，而且受到不同声学的影响，其中之一是高速流动压力波动引起的气动声学。最先进的结构声波疲劳分析是通过使用均匀分布的随机高斯白噪声 (WGN) 进行的。然而，均匀分布的激励通常与实际情况不一致，该方法的有效性有待进一步研究。在本研究中，提出了一种非线性降阶模型 (NLROM) 来计算各向同性板和复合板的非线性响应。NLROM 基于有限元 (FE) 模型，并通过全阶系统在小子空间上的伽辽金投影构建。NLROM 的输入是气动和气动声学载荷，由大涡模拟 (LES) 计算并使用径向基函数 (RBF) 从空气动力学网格插入到结构节点。各向同性板和复合板的非线性响应由 NLROM 计算并与 WGN 进行比较。结果表明，与直接有限元模拟相比，NLROM 提供了近一个数量级的加速，并预测了比 WGN 更短的声波疲劳寿命。