硝基甲烷中爆轰波绕射的实验研究和数值模拟

EXPERIMENTS AND NUMERICAL SIMULATIONS ON THE DIFFRACTION OF DETONATION WAVES IN NITROMETHANE

叙述了对硝基甲烷中拐角分别为６０°、９０°、１２０°三种情形的爆轰波绕射现象进行的实验研究。实验上观测到爆轰波绕过９０°、１２０°拐角时有未反应的“死区”，而且拐角增大时“死区”变大，绕射爆轰波可以近似地按爆心在拐角顶点附近变化的散心爆轰波看待。从数值模拟和理论分析得出，爆轰波绕射时硝基甲烷的化学反应不同于正常爆轰，拐角顶点附近各处反应速率不同，出现部分反应区和未反应区。

The experimental studies on the diffraction of detonation waves passing round 60°、90°and 120°convex angles in nitromethane (NM)are described in this paper. The results indicate that there is unreacted “dead zone” for the case of 90°or 120°convex angle and the“ deadzone”increases with the con vex angle. The diffractive detonation waves can be approximatelyconsidered as a series of cylindrically divergent detonation waves with initiation axies or centerschanging nearby the tops of the convex angle. The numerical simulations and theoretical analysisshow that the characteristics of chemical reaction in the diffraction zone of detonation wave in NM may be different from that normal detonation to some extent,The reaction rate of NM indiffraction of detonation wave nearby the top of convex angle changes and there exist beth partially reacting and unreacting zones there.