柱面气相散心爆轰波胞格演化规律研究

本文采用二阶精度NND格式,应用改进的二阶段化学反应模型,通过求解二维Euler方程对柱面气相散心爆轰波胞格演化过程进行了数值模拟.计算结果表明在传播过程中,空间尺度的扩张导致了散心爆轰波后气流的自然膨胀,使得多波结构的爆轰阵面呈现出显著的胞格自组织特性.根据计算结果与理论分析,本文归纳了五种胞格演化模式,分别命名为内凹波阵面会聚、波阵面扭结、褶皱波面失稳、胞格自合并和三波点滑移,并定义了各种模式的物理特征,分析了其相关的演化机制和规律.

Study on evolution mechanisms of cylindrically-diverging gaseous detonations

The evolution of cylindrically-diverging gaseous detonation has been numerically investigated by solving Euler equations implemented with an improved two-step chemical kinetic model and NND scheme.The expansion of the diverging space leads to the self-organization of traverse waves and cellular cell bifurcation during the detonatio:propagation,which results in roughly constant cell size as detonation front continuously expanding.From numerical results,five major modes for the wave front evolution are identified,named as the concave front focusing,the kinked wave front evolution,the wrinkled wave front instability,the self-merging of cells and the triple-point trajectory slipping,respectively,and the physical characteristics and propagation mechanisms related to each mode are examined carefully and explained in detail.