火星科学实验室气动特性数值分析

NUMERICAL AERODYNAMIC ANALYSIS OF MARS SCIENCE LABORATORY

针对火星着陆探测器进入-下降-着陆过程的高超声速进入阶段,求解三维流体动力学Navier-Stokes方程与化学反应动力学模型,分析火星科学实验室进入火星大气时的化学非平衡效应、探测器周围的流场结构和气动特性在化学非平衡效应影响下的变化.结果表明,CO2在激波后大量分解,消耗大量能量;在化学非平衡效应影响下,探测器头部激波脱体距离大幅减小,尾迹旋涡运动减弱;化学非平衡效应影响下探测器升力系数变化不大,阻力系数高于完全气体,升阻比略低,配平攻角小于完全气体.

Based on the hypersonic entry in the entry-descending-landing procedure, the three-dimensional Navier-Stokes equations are solved by a parallel code to analyze the flow field structures, the aerodynamic characteristics and their variation patterns of the Mars Science Laboratory entering the Martian atmosphere with and without the chemical reaction models. The analysis shows that a large number of C02 is dissociated behind the shock and much energy is consumed, with the chemical non-equilibrium effect, the shock layer is strongly compressed. The comparisons between the real gas and the perfect gas show that the vortex in the wake flow is reduced, the positions of the separation lines and the singularity are distinctly different; under the chemical non-equilibrium condition, the lift coefficient almost keeps the same, the drag coefficient increases, the lift-to-drag ratio and the pitch moment are smaller than those of the perfect gas.