飞行器阵风响应的CFD-6DOF仿真分析

飞行器在大气中飞行,不可避免地受到阵风的影响。阵风所附加的气动载荷引发飞行器飞行状态的改变,过大幅值的阵风影响飞行的性能与安全。针对这种状况,首先采用改进的Lamb-Ossen涡模型,建立尾涡形式的阵风场;然后采用基于CFD技术的非定常N-S方程求解,并在计算网格中引入"网格速度"来模拟阵风,对SWIM(Subsonic Wall Interference Model)尾涡中的定常气动特性进行验证;最后通过CFD-6DOF的耦合,对SWIM俯冲穿越尾涡场的飞行轨迹进行研究。结果表明:计算结果与实验值符合较好;SWIM在尾涡中飞行时出现抖动、下沉、改变飞行状态、剧烈翻转的现象,与实际飞行器进入尾涡中的轨迹特性类似。

The CFD-6DOF Simulation Analysis of Aircraft Gust Response

Aircraft gust response refers to the transient change of aircraft flight parameters ,the structure load conditions in the event of gusts. The additional aerodynamic gust loads will lead to changes in aircraft flight status , gusts over substantial value will affect the performance and safety of flight. In view of this situation , this paper based on CFD technology to solve unsteady N-S equations , introduces " grid speed" in the computing grid to simulate gusts , and research aircraft gust response in time domain. First calculate aerodynamic characteristics of three-dimensional aircraft model SWIM (Simple Wake Follower Model) in the trailing vortex , CFD calculation results with the results of wind tunnel experiments , literature CFD results are in good agreement ; Then simulate the flight path of SWIM diving across trailing vortex field , achieving the CFD-6DOF trajectory simulation of SWIM in the trailing vortex. Trajectory simulation results show that the jitter , sinking , changing flight conditions , intense flip phenomena occur while SWIM flying in trailing vortex are similar with the trajectory characteristics of aircraft flying into the wake vortex.