气相爆轰波沿胞格的动力学机理研究

 建立了一种以子单元分析为基础，研究气相爆轰波沿胞格运动时的动力学机理的新方法。根据该子单元的性质和斜冲击波关系，首先推导了对撞前后前导冲击波沿胞格对称轴的马赫数之比和入射冲击波入射角及胞格几何性质的关系，求解了胞格结构中的三波点对撞问题。然后，采用爆炸波模拟前导冲击波的自持运动过程，求解气相爆轰波沿胞格的动力学过程，理论分析表明，气相爆轰波在胞格起点首先经历一个增长过程，然后才出现衰减。理论分析结果与实验和数值计算结果的比较表明符合得较好。

STUDY ON DYNAMIC MECHANISM OF CELLULAR STRUCTURE

In this paper,the regular detonation cells were divided into the primary units,referred to as sub cells of cellular detonation.By examining the dynamic process of detonation waves propagating along these sub cells,theoretical analysis was conducted to study the dynamic mechanism of the two dimensional idealized detonation waves in gaseous mixtures.Based on the theory of oblique shock waves,a analytical formula was derived to describe the relation between the Mach number ratio through triple shock collision and the geometric properties of detonation cells.From this formula the incident angle can be also calculated.By applying a modified blast wave theory,an analytical model was developed to predict the dynamic process of detonation waves along the sub cell.The results calculated from the analytical model show that detonation waves are ,first ,strengthened at the beginning of the sub cell after triple shock collisions,and then decay until the detonation waves reach the sub cell end.These analytical results were compared with experimental data and previous numerical results,the agreement between them appears to be good,in general.