面向控制的弹性高超声速飞行器建模方法研究

A Control-Oriented Modeling for Flexible Air-Breathing Hypersonic Vehicle

高超声速飞行器广泛采用升力体、乘波体等气动布局和轻质材料,导致飞行器刚体模态与弹性模态的耦合问题突出。针对该类飞行器的特点,使用有限元方法基于变截面自由梁构建高超声速飞行器的结构弹性模型,利用当地流活塞理论计算弹性变形引起的非定常气动力,然后借助均匀设计、逐步回归等统计学方法获取弹性高超声速飞行器的高精度曲线拟合模型。仿真对比分析表明,所介绍的高超声速飞行器弹性建模方法高效、可靠,其所建立的曲线拟合模型与原始物理模型的一致程度及精度均优于现有拟合模型,而所消耗的时间与计算机资源小于现有建模方法。

The wide use of lifting body and wave-rider aerodynamic layout causes difficulty in the coupling between the rigid modal of a flexible air-breathing hypersonic vehicle and its elastic modal. Hence we use the finite element method and the variable cross-section free beam to establish the control-oriented structural elastic model of the hy-personic vehicle. We apply the first-order local flow piston theory to calculate its unsteady aerodynamic force. Then we use the uniform design method and the step-by-step regression analysis method to establish its high-precision curve fitting model （ CFM） . The simulation results, given in Figs.3 and 4, and their comparison show preliminarily that：the CFM established with the control-oriented elastic modeling method agrees well with the physical model of the hypersonic vehicle, while consuming less computing time and resources than other traditional modeling methods.