中文摘要：

对马赫数为6.5的H2/空气预混气体来流,采用带化学反应的多组分Euler方程,在半锥角为32°的圆锥体诱导下的爆燃和爆轰波结构及其不稳定性进行了数值研究。利用文献[7]实验结果验证了数值模型和计算网格的可靠性。计算结果表明,圆锥激波诱导的燃烧包含爆轰和爆燃两个基本形态,两者在空间上呈现出较规则的不稳定结构,而在时间进程上呈现出两种形态交替出现的周期振荡燃烧不稳定现象。爆轰过程的空间不稳定结构由多个基本的三波点结构叠串而成,而爆燃过程中的反应阵面则呈现出锯齿形状。在一个振荡燃烧周期内,爆燃和爆轰的不稳定性受三波点波系结构、化学反应诱导区内未燃气体的热力学状态以及壁面反射波扰动的影响,表现出爆燃过程中化学反应诱导区长度沿圆锥壁面不断增加和爆轰过程中长度不断缩短的特有现象。研究结果对超燃冲压发动机或驻定爆轰发动机的燃烧室设计有参考意义。

英文摘要：

Numerical simulation was carried out to investigate the structures and instabilities of deflagration and detonation waves induced by an incoming flow of stoichiometric H2/air premixed gas with Mach Number 6.5 over a cone with half cone angle 32°,based on the multi-component Euler equations with chemical reactions.The reliabilities of numerical model and computational grid were verified using the experimental results in Literature[7].The numerical results show that the combustion induced by conical shock wave includes both detonation and deflagration modes.Both the modes,which can alternately appear,show the regularly spatial instability and the temporally periodic oscillation instability.The regularly spatial unstable detonation is regarded as a coalescence of the basic triple wave structures,while the unstable deflagration shows a zigzag reaction front.In an oscillation combustion period,the evolution of detonation and deflagration modes is affected by triple wave structure,thermodynamics of unburned gas in the reaction induction region and disturbance of reflected waves from wall,and shows the distinct phenomena of which the chemical reaction induction length increases along the cone wall during the deflagration process and decreases during the detonation process.The results are significant for the combustion chamber design of scramjet or standing detonation engine.