采用改进的CE/SE方法模拟方管中氢氧爆轰波的稳定传播结构

采用改进的时空守恒元/解元（CE/SE）格式和新型二步化学反应模型,对小扰动情况下方管通道中的氢氧气相爆轰传播过程进行了数值模拟,对不同截面尺寸和两种扰动模式下的爆轰波三波线结构进行了详细计算和分析。数值模拟花费了相对较少的计算代价,清晰地得到了方形截面通道中3种相对稳定的爆轰波传播结构,即直角模式、对角模式和螺旋模式。随着截面尺寸的减小,爆轰波胞格图样与波阵面结构随之产生适应性的变形,乃至出现胞格数目的减少和部分三波线的消失;最终,直角模式和对角模式都会转化为顺时针或逆时针的螺旋模式;临界尺寸下,得到了转换过程中新的过渡结构和压力脉冲振幅的变化,并以此初步讨论了直角和对角传播模式的稳定性。

Simulations of stable structure in oxy-hydrogen detonation propagation in square ducts using an improved CE/SE scheme

Using an improved space-time Conservation Element and Solution Element (CE/SE) scheme, the three-dimensional detonation propagation in square ducts filled with H₂-O₂ mixtures is simulated. A series of detonation structures under different cross-sectional sizes and two kinds of initial perturbation are calculated and analyzed. It costs relatively little computational resource to reproduce the three typical kinds of detonation propagation structure, namely the rectangular mode, the diagonal mode, and the spinning mode. As the cross-sectional size decreases, the detonation cellular pattern and the wave front structure will produce an adaptive deformation, until the number of cellular pattern decreases and some of the triple point lines disappear. Eventually, the rectangular mode and the diagonal mode will both transform into the clockwise or anticlockwise spinning mode. At the critical cross-sectional size, the new detonation structure and its maximum pressure histories during the transformation process are obtained, and the stability of the rectangular and diagonal propagation mode are preliminarily discussed.