流场求解采用3维雷诺平均N-S方程,分别利用ROE格式和二阶中心格式对对流通量和粘性通量进行离散处理;用高斯-赛德尔隐式格式对方程进行时间推进求解, 采用k-ε两方程模型用于湍流的数值模拟。采用几何光学结合物理光学方法分析平均流动和湍流对光场的影响。计算结果表明:由于窗口外形曲面的曲率不同, 两种窗口外部流场存在较大区别, 气流速度、密度的分布情况各不相同。曲率较大的窗口外形对气流的压缩程度较大, 导致气流绕过窗口顶端中心区域时流速快, 密度梯度大, 因而窗口空气阻力较大, 光束在该窗口流场中传输受气流影响的影响也较大

This paper studies the optical aberrations in the case when the optical beam is propagating through the flow field of two optical windows with different shapes,respectively.The flow field is governed by the the 3-D Reynolds averaged Navier-Stokes (N-S)equations.To split the viscosity flux and the convective flux of the N-S equations, the second order central scheme and the ROE scheme are adopted respectively.With the implicit Gauss-Seidel scheme, the code is advanced in time.The k-ε turbulence model is used for turbulence simulations.Aero-optic effects are analyzed with the methods of geometrical optics and physical optics by introducing the mean flow and turbulence.The numerical results show that the beam quality and drag coefficient would be significantly influenced by the shape of optical window, thus the optimization of the shape of optical window is very important.