Detonation Simulations in Supersonic Combustible Mixtures with Nonuniform Species

作者：Cai, Xiaodong; Liang, Jianhan^*; Deiterding, Ralf; Lin, Zhiyong

来源：AIAA Journal, 2016, 54(8): 2449-2462.

DOI：10.2514/1.J054653

Adaptive high-resolution simulations of gaseous detonation using a hot-jet initiation were conducted in supersonic combustible mixtures with spatially nonuniform species. The two-dimensional Euler equations were used as the governing equations in combination with a detailed hydrogen-oxygen reaction model. Three different groups of mixtures, which represent various degrees of chemical reactivity, were investigated. The results show that, when the mixtures generally have a high degree of chemical reactivity, detonation initiation can eventually be realized successfully byMachreflection as well as the deflagration-to-detonation transition mechanism, independent of the spatial distribution of the mixtures in the channel. A recurring four-stage sequence of detonation initiation, detonation attenuation, initiation failure, and detonation reinitiation can be identified. When the mixtures generally have an intermediate degree of chemical reactivity, detonation combustion can be fully realized in the channel, where different overdrive degrees are found in the upper and lower halves. After the shutdown of the hot jet, the overdriven detonation attenuates gradually, and eventually a slightly overdriven detonation and a slightly underdriven detonation are generated, which can be regarded as a new stable state of propagation. However, whether a detonation can be initiated successfully is determined by the spatial mixture distribution. In mixtures with low degree of chemical reactivity, detonation initiation can generally not be realized. In this case, successful detonation initiation should be realizable by using of a stronger hot jet.

• 出版日期2016-8
• 单位中国人民解放军国防科学技术大学