类Starship飞行器大迎角动态特性数值研究

Numerical Simulation of Dynamic Derivatives for Starship-Like Spacecraft at High Angles of Attack

再入飞行器的动态稳定性是其任务成败的关键因素,因此有必要对新型类Starship飞行器大迎角动态特性进行深入研究。为辨识动导数,采用基于分区弹簧近似法动网格技术的非定常N-S方程求解器开展强迫振动的数值仿真。有限体积离散采用Roe格式及SST湍流模型,时间方向采用全隐式GMRES方法进行迭代求解。在高超声速弹道外形(Hyper ballistic shape,HBS)标模验证的基础上,获得了类Starship飞行器典型大迎角状态下不同飞行马赫数、重心位置、操纵面偏转角、迎角和减缩频率的俯仰动导数变化规律:典型状态下,俯仰动导数超声速时为负,亚声速时为正;随不同因素的变化,Ma=0.3和Ma=5.0时的俯仰动态特性差异明显;高速下操纵面上偏会导致阻尼减小,且后翼影响更显著。计算结果表明了本文方法在宽速域、大空域复杂外形飞行器动态特性辨识中的应用价值。

The dynamic stability of the re-entry vehicle is a key factor in the success or failure of its mission.So it is necessary to conduct in-depth research on the dynamic characteristics of the new Starship-like spacecraft at high angles of attack.To evaluate the dynamic derivatives,numerical simulations of forced vibrations are performed using an unsteady N-S equation solver based on the partitioned spring approximation dynamic mesh technique.The finite volume discretization adopts Roe format and SST turbulence model,and the time direction adopts fully implicit GMRES method for iterative solution.Based on the verification of the hyper ballistic shape(HBS)standard model,the variation law of pitch dynamic characteristics of different flight Mach numbers,centers of gravity position,deflection angles of control surface,angles of attack,reduction frequencies under the typical high angle of attack state of Starship-like spacecraft is obtained.In the typical state,the pitch dynamic derivatives are negative at supersonic speed and positive at subsonic speed.With the change of different factors,the pitch dynamic characteristics of Ma=0.3 and Ma=5.0 are significantly different.At high speed,the deflection of the control surface can reduce the damping,and the influence of the rear wing is more significant.The calculation results show the application value of the method in the identification of the dynamic characteristics of the complex-shaped aircraft in wide speed and large airspace.