Influence of chemical kinetics on detonation initiating by temperature gradients in methane/air
Influence of chemical kinetics on detonation initiating by temperature gradients in methane/air
复制标题
化学动力学对甲烷/空气中温度梯度起爆的影响
DOI：
10.1016/j.combustflame.2018.08.017
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发表时间：
2018-10
期刊：
影响因子：
--
通讯作者：
Michael A. Liberman
中科院分区：
文献类型：
--
作者：
Cheng Wang;Chengeng Qian;JianNan Liu;Michael A. Liberman
研究了不同的简化和详细化学模型及其对甲烷/空气混合物中初始温度梯度引发的燃烧状态模拟的影响。反应波传播范围的限制取决于自发波速度和问题的特征速度。本研究主要集中于确定发生爆炸所需的条件，并比较简化化学模型和详细化学模型之间的差异。结果表明，广泛使用的简化化学方案，例如一步、两步和其他简化模型，不能正确再现甲烷/空气混合物中的点火过程。使用简化模型计算的点火延迟时间比使用详细化学模型计算并通过实验测量的点火延迟时间短几个数量级。这导致放热反应显着影响自发反应波和压力波的点火、演化和耦合的时间显着不同。我们表明，使用详细的化学模型计算出的能够触发爆炸的温度梯度比使用简化的化学模型进行模拟所预测的要浅得多（热点的尺寸要大得多）。这些发现表明，导致爆燃到爆炸转变 (DDT) 的场景可能很大程度上取决于模拟中使用的化学模型，并且 Zeldovich 梯度机制不一定是触发 DDT 的通用机制。所获得的结果表明，应谨慎对待使用简化化学模型模拟滴滴涕所得出的结论。
Different simplified and detailed chemical models and their impact on simulations of combustion regimes initiating by the initial temperature gradient in methane/air mixtures are studied. The limits of the regimes of reaction wave propagation depend upon the spontaneous wave speed and the characteristic velocities of the problem. The present study mainly focus to identify conditions required for the development a detonation and to compare the difference between simplified chemical models and detailed chemistry. It is shown that a widely used simplified chemical schemes, such as one-step, two-step and other simplified models, do not reproduce correctly the ignition process in methane/air mixtures. The ignition delay times calculated using simplified models are in orders of magnitude shorter than the ignition delay times calculated using detailed chemical models and measured experimentally. This results in considerably different times when the exothermic reaction affects significantly the ignition, evolution, and coupling of the spontaneous reaction wave and pressure waves. We show that the temperature gradient capable to trigger detonation calculated using detailed chemical models is much shallower (the size of the hot spot is much larger) than that, predicted by simulations with simplified chemical models. These findings suggest that the scenario leading to the deflagration to detonation transition (DDT) may depend greatly on the chemical model used in simulations and that the Zeldovich gradient mechanism is not necessary a universal mechanism triggering DDT. The obtained results indicate that the conclusions derived from the simulations of DDT with simplified chemical models should be viewed with great caution.
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DOI：
10.1007/bfb0035362
发表时间：
1991
期刊：
--
影响因子：
--
作者：
M. Smooke
通讯作者：
M. Smooke
DOI：
10.1103/physreve.85.056312
发表时间：
2012-05
期刊：
Physical review. E, Statistical, nonlinear, and soft matter physics
影响因子：
--
作者：
M. Liberman;A. Kiverin;M. F. Ivanov
通讯作者：
M. Liberman;A. Kiverin;M. F. Ivanov
影响因子：
4.1
作者：
Jiang, GS;Shu, CW
通讯作者：
Shu, CW
DOI：
10.1016/j.actaastro.2010.05.024
发表时间：
2010-10
期刊：
--
影响因子：
--
作者：
M. Liberman;M. F. Ivanov;A. Kiverin;Mike Kuznetsov;A. Chukalovsky;T. Rakhimova
通讯作者：
M. Liberman;M. F. Ivanov;A. Kiverin;Mike Kuznetsov;A. Chukalovsky;T. Rakhimova
影响因子：
4.4
作者：
L. Bates;D. Bradley;Günter Paczko;N. Peters
通讯作者：
L. Bates;D. Bradley;Günter Paczko;N. Peters