返回舱动态稳定性分析及被动控制方法研究

耦合求解非定常可压缩Navier-Stokes方程和刚体运动方程,数值模拟返回舱跨声速俯仰自由振动过程,探讨返回舱前后体对动态稳定性的影响及其被动控制方法.研究结果表明：在俯仰振动过程中,返回舱前体对流场做正功,释放返回舱振动能量,抑制振幅增加;而返回舱后体对流场做负功,增加返回舱振动能量,导致振幅增加,当两者相等时,振动进入极限环状态.在上述物理机理分析基础上,本文给出六种不同的返回舱后体修改方案,并采用数值模拟方法研究不同的后体外形对返回舱俯仰自由振动幅度和频率特性参数的影响,研究结果可为返回舱设计及动态稳定性的控制方法提供依据.

Analysis of dynamic stability and research of passive control method for capsule

The freedom pitching motions of capsule at transonic flow were simulated numerically by coupling solving unsteady compressible Navier-Stokes equations and Euler equation of rigid-body dynamics. The effects of fore-body/aft-body of capsule to dynamic stability and the passive control method for capsule were discussed in this paper. During the free oscillation in pitching, the front part of the capsule conducts work to the flow field, the quantity of the capsule energy gets less and the swing is restrained. The rear part of the capsule gains energy from the flow field, the quantity of the capsule energy gets greater and the motion is considered as being unstable. When the two quantity of the capsule energy get equal, the capsule motion falls into a limited cycle oscillation. Under these discusses, six capsule models whose aft-bodys were modified by different manner were given. The effect of different aft-body shapes on the dynamic stability in pitching, including the amplitude and frequency, was studied by numerical simulation methods. The research will supply reference to the design of capsule and its passive control of dynamic stability.