非平衡流解耦方法及其计算激波诱导燃烧的应用验证

Validation of an uncoupled solver of non-equilibrium flow for shock-induced combustion

介绍并发展了一种改进的化学非平衡流动解耦方法.将流动控制方程与化学反应生成源项解耦处理,组分对流项的矢通量分裂基于流动方程密度对流项的分裂形式给出.对流项采用五阶WENO格式求解,化学反应源项的刚性采用简化的隐式方法进行处理.将该方法应用于预混H2/O2和H2/Air激波诱导燃烧计算,得到的定常及非定常燃烧过程与实验观测相符,振荡频率与实验测量较吻合,结果表明该方法应用于多组分多步反应流计算是可行的.

An improved uncoupled solver of non-equilibrium flow was introduced and de veloped in this study. The splitting of convective species flux was uncoupled from the N S equations and based on the splitting result of the convective density flux. Inviscid flux was calculated with fifth order weighted essentially non-oscillatory scheme. Simplified implicit formulation was adopted to deal with the stiffness generated by the chemical reacting source term of every separate species equation. Shock-induced combustion phenomena of a blunt body in stoichiometric H2/O2 and H2/Air mixture were calculated to validate the solver. The steady and unsteady shock induced combustion flowfields agree favorably well with the experimental observation. Oscillating frequencies of unsteady case agree well with the experi mental data. The results indicate that the method is sufficiently efficient in the application to multi species and multi-reaction flow.