Role of transversal concentration gradient in detonation propagation
Role of transversal concentration gradient in detonation propagation
复制标题
横向浓度梯度在爆炸传播中的作用
DOI：
10.1017/jfm.2019.37
复制
发表时间：
2019-02
影响因子：
3.7
通讯作者：
Chung K.Law
中科院分区：
文献类型：
--
作者：
Wenhu Han;Cheng Wang;Chung K.Law
通过高分辨率模拟研究了横向浓度梯度在充满$\text{H}_{2}{-}\text{O}_{2}$混合物的二维通道中爆轰传播中的作用。结果表明，与均匀介质中的传播相比，浓度梯度降低了平均爆轰速度，因为到达下游反应平衡的延迟，导致大量未反应的$\text{H}_{2}$，从而导致明显的物种波动。横向浓度梯度也增强了细胞爆轰不稳定性。陡坡化大大减少了前缘三重点的数量，平均延长了整体爆轰前缘结构，从而增加了平均爆轰速度的亏缺。进一步发现，前导激波与横向浓度梯度的相互作用影响了局部凸起的形成，从而影响了前方后方未反应袋的形成，而横波则引起了下游残余燃料的混合和燃烧。然而，当浓度梯度变陡时，存在横向爆轰，并通过先导激波消耗压缩区和预热区的燃料；因此，当单头传播模式接近极限时，爆轰速度亏缺不会明显增加。
The role of a transversal concentration gradient in detonation propagation in a two-dimensional channel filled with an $\text{H}_{2}{-}\text{O}_{2}$ mixture is examined by high-resolution simulation. Results show that, compared to propagation in homogeneous media, a concentration gradient reduces the average detonation velocity because of the delay in reaching downstream reaction equilibrium, leading to a large amount of unreacted $\text{H}_{2}$ and hence significant species fluctuations. The transversal concentration gradient also enhances the cellular detonation instability. Steepening it reduces considerably the number of triple points on the front, lengthens the global detonation front structure on average and consequently increases the deficit of the average detonation velocity. It is further found that the interaction of the leading shock with the transversal concentration gradient influences the formation of local $\text{H}_{2}$ bump and thus the unreacted pocket behind the front, while the transverse wave causes mixing and burning of the residue fuel downstream. Nevertheless, for the steepened concentration gradient, a transverse detonation is present and consumes the fuel in the compressed and preheated zone by the leading shock; consequently, the detonation velocity deficit is not increased significantly for detonation with the single-head propagation mode close to the limit.
登录
查看更多内容
影响因子：
2.2
作者：
L. R. Boeck;F. Berger;J. Hasslberger;T. Sattelmayer
通讯作者：
L. R. Boeck;F. Berger;J. Hasslberger;T. Sattelmayer
影响因子：
4.4
作者：
G. Thomas;P. Sutton;D. Edwards
通讯作者：
G. Thomas;P. Sutton;D. Edwards
DOI：
10.1007/bf00742862
发表时间：
1975
期刊：
Combustion, Explosion and Shock Waves
影响因子：
--
作者：
V. Subbotin
通讯作者：
V. Subbotin
DOI：
10.1063/1.4798459
发表时间：
2013-04
期刊：
The Journal of chemical physics
影响因子：
--
作者：
Xian-ming Wang;C. Law
通讯作者：
Xian-ming Wang;C. Law
影响因子：
3.7
作者：
X. Mi;E. Timofeev;A. Higgins
通讯作者：
X. Mi;E. Timofeev;A. Higgins