矩形管内临界爆轰动力学数值分析

 对矩形管内临界爆轰动力学特征进行了数值分析。采用基元反应描述爆轰化学反应过程，采用二阶附加半隐的龙格-库塔法和5阶WENO格式求解二维反应欧拉方程。对于25%氩稀释化学计量比的氢氧预混气体，当管道宽度为30 mm、初温为300 K时，产生临界爆轰的预混气体初压为3.5 kPa。在此临界条件下，获得了临界爆轰胞格结构、沿壁面的速度和峰值压力曲线及流场波系演变特征。着重对比分析了矩形管内临界爆轰与普通爆轰在爆轰波速度、平均速度、胞格宽长比、横波结构、未反应气囊及旋涡结构之间的差异，深入认识了临界爆轰的不稳定性和化学反应动力学特征。

Numerical Analysis of Marginal Detonation Dynamics in a Rectangular Tube

Marginal detonation dynamics in a rectangular tube was numerically analyzed in this paper.The detailed chemical reaction model was employed to describe the heat release of detonation chemical reactions.The 2nd additive semi-implicit Runge-Kutta method and 5th order Weighted Essentially Non-Oscillatory(WENO) scheme were used to integrate the two-dimensional time-dependent reactive Euler equations.For the stoichiometric hydrogen and oxygen mixture diluted by 25% argon,as the channel width is 30 mm and the initial temperature is 300 K,the critical initial pressure for marginal detonation is 3.5 kPa.Under this critical condition,the cellular pattern,the velocity and maximum pressure along the wall and the wave evolution of marginal detonation were obtained.The difference between the marginal and ordinary detonation was discussed including the detonation velocity,average velocity,the ratio of cell width to length,transverse wave structure,unreacted gas pocket and vortex structure.The intrinsic instability and chemical dynamics characteristics of marginal detonation were deeply recognized.