Theoretical approach to one-dimensional detonation instability  

作　　者：Chun WANG Gaoxiang XIANG Zonglin JIANG 

机构地区：[1]State Key Laboratory of High Temperature Gas Dynamics, Chinese Academy of Sciences

出　　处：《Applied Mathematics and Mechanics(English Edition)》2016年第9期1231-1238,共8页应用数学和力学（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(No.90916028);the Innovation Program of the State Key Laboratory of High Temperature Gas Dynamics of Institute of Mechanics,Chinese Academy of Sciences

摘　　要：Detonation instability is a fundamental problem for understanding the microbehavior of a detonation front. With the theoretical approach of shock dynamics, detonation instability can be mathematically described as a second-order ordinary difference equation. A one-dimensional detonation wave can be modelled as a type of oscillators. There are two different physical mechanisms controlling the behaviors of a detonation. If the shock Mach number is smaller than the equilibrium Mach number, the fluid will reach the sonic speed before the end of the chemical reaction. Then, thermal chock occurs, and the leading shock becomes stronger. If the shock Mach number is larger than the equilib- rium Mach number, the fluid will be subsonic at the end of the chemical reaction. Then, the downstream rarefaction waves propagate upstream, and weaken the leading shock. The above two mechanisms are the basic recovery forces toward the equilibrium state for detonation sustenance and propagation. The detonation oscillator concept is helpful for understanding the oscillating and periodic behaviors of detonation waves. The shock dynamics theory of detonation instability gives a description of the feedback regime of the chemical reaction, which causes variations of the leading shock of the detonation. Key words detonation wave, detonation instability, shock wave, chemical reactionDetonation instability is a fundamental problem for understanding the microbehavior of a detonation front. With the theoretical approach of shock dynamics, detonation instability can be mathematically described as a second-order ordinary difference equation. A one-dimensional detonation wave can be modelled as a type of oscillators. There are two different physical mechanisms controlling the behaviors of a detonation. If the shock Mach number is smaller than the equilibrium Mach number, the fluid will reach the sonic speed before the end of the chemical reaction. Then, thermal chock occurs, and the leading shock becomes stronger. If the shock Mach number is larger than the equilib- rium Mach number, the fluid will be subsonic at the end of the chemical reaction. Then, the downstream rarefaction waves propagate upstream, and weaken the leading shock. The above two mechanisms are the basic recovery forces toward the equilibrium state for detonation sustenance and propagation. The detonation oscillator concept is helpful for understanding the oscillating and periodic behaviors of detonation waves. The shock dynamics theory of detonation instability gives a description of the feedback regime of the chemical reaction, which causes variations of the leading shock of the detonation. Key words detonation wave, detonation instability, shock wave, chemical reaction

关 键 词：detonation wave detonation instability shock wave chemical reaction 

分 类 号：O38[理学—流体力学]