摘要
本文对非平衡化学区应高超声速绕流零攻角轴对称钝头体电离空气粘性流动进行了研究,通过带有化学源项的Navicr-Stokes方程对流动作数值模拟,总的连续方程由单个组元守恒方程代替。高温电离空气中存在7个主要的组元,它们依次为N_2,O_2,NO,NO ̄+,N,O,和e ̄-。化学动力学模型由7个组元和这些组元之间6个可能的反应来描述。发展了一种数值方法以求解这组完全耦合的与时间有关的偏微分方程组。利用一类新的有限差分方法来求解这组以守恒形式表示的控制方程。这是一种以TVD格式来离散粘性流通量的方法。在数值实验中采用了TVDYee-Harten格式,对全部算例都是用激波捕捉法。关于化学组元,我们试图处理完全催化壁、非催化壁和有限催化壁等三种不同的表面边界层条件。计算是对RAMC-Ⅱ试验条件进行的,得出了71km高空情形的典型流场数值解。对表面压力,Stanton数和热流率给出了化学反应气体结果与完全气体结果的比较。计算的流场电子密度与RAMC-Ⅱ实验数据进行了比较,计算结果与实验数据符合是相当好的。
Nonequilibrium reacting hypersonic ionizing air viscous flows over axisymmetric blunt bodies at zero incidence are investigated and numerically simulated by the Navier-Stokes equations with the chem-icalsource terms.The global continuity equation is replaced by the indi-vidual species conservation equations.For the high temperature ionized air there are seven primary constituents:N_2,O_2,NO, NO ̄+,N,O,and e ̄-.Chemical kineties are described by 7 species and 6 possible reactions bet-ween these species.A numerical method to solve the fully coupled time-de-pendent partial differential equations has been developed.The governing e-qautions in conservation form are solved using a new class of finite-differ-ence solution procedure in which the viscous fluxes are discretized according to TVD Yee-Harton schemes.All the computations are performed using shock-capturing methods.Three different surface boundary conditions(full-y-catalytic,fully non-catalytic,and finite catalytic walls)are tried for the chemical species. Numerical solutions are obtained to replicate the RAMC-Ⅱ flight with the typical flowfield solution in the 7lkm case,Comparisons of the re-acting gas results with the surface pressure and Stanton number obtained for a perfect gas are presented.The agreement between the calculated results and the RAMC-Ⅱ experimental data for eletron density is quite good.
出处
《空气动力学学报》
CSCD
北大核心
1995年第2期192-199,共8页
Acta Aerodynamica Sinica
基金
国家自然科学基金
关键词
非平衡粘性流
NS方程
激波捕捉法
化学动力学
nonequilibrium viscous flow,Navier-Stokes equation,shock-capturing methods,TVD scheme,chemical kinetics.