某型超声速半流伞气动热及气动特性研究

Research on Simulation of Aero-heating and Aerodynamic Characteristics for Supersonic Half-flow Parachute

多用途飞船返回舱将以自旋方式半弹道再入大气层。返回舱再入飞行过程中,在超声速段存在第二个配平点,有可能出现姿态翻滚的情况。为避免返回舱姿态的不确定引起减速伞的开伞故障,返回舱配备了一个稳定伞,该稳定伞采用半流伞型,开伞高度约为26km,开伞时伞船系统Ma=3.0。因此,该降落伞面临非常严重的气动加热情况。文章基于计算流体力学(computational fluid dynamics,CFD)方法,验证了简化模型的可靠性,并对二维模型进行仿真,得到了降落伞及流场的速度分布、压力分布、温度分布。可以看出:相同高度下,随着速度值的增大,流场的动压值也是在增大的;相同马赫数下,随着高度的降低,流场的动压值也在增大;伞衣内表面温度始终是要高于外表面温度,且伞面温度最高的区域都处于伞顶口附近的伞带内表面上。

The reentry capsule of multi-purpose spaceship returns to the atmosphere in a spinning Semi-ballistic mode. According to the aerodynamic calculation results of a reentry capsule, the aerodynamic characteristics of movable guide coefficient calculations display that the second trim point exists in supersonic flight which may lead capsule attitude pitching. In order to avoid drogue parachutes failing to deploy, the capsule is equipped with a stable parachute. For the stable parachute a half-flow type is selected. The height of deployment is about 26 km. The speed of parachute-spaceship system when the parachute deploys is about 3Ma.So, the aero-heating in supersonic speed needs to be considered when designing the parachute. In the article, the dynamic characteristics and aero-heating of supersonic half-flow parachute are calculated with the method of CFD, the simplified model is reliable and the 2D models are simulated. Some conclusions are got： For the same height, the value of the dynamic pressure in the flow field is increased with the speed increase; For the same speed, the value of the dynamic pressure in the flow field is increased with the speed decrease; The heating of inner surface is higher than that of outer surface, and the maximum temperature region is located on the inner surface of the top parachute.