激波聚焦火焰聚心起爆器的数值研究

针对短距离内的激波聚焦起爆问题,设计了一种激波聚焦火焰聚心起爆结构,通过数值模拟方法对该结构内部流场变化进行研究。结果表明:加速区是火焰失稳加速的重要区域；聚焦区能量汇聚造成局部爆炸是燃烧转爆轰加速的关键因素,且该区域内由于几何结构形成的卷吸涡能够增强聚焦并阻碍激波回传入加速区；稳燃区主要实现爆轰波从过驱状态到稳定爆轰状态的过渡区。确定中心轴线上温度、压力波动是由于聚焦腔聚焦作用造成的,而爆轰波锋面温度压力变化是由于三波点运动造成。 

Numerical investigation of detonator with shock focusing and flame implosion

In order to solve the problem of shock wave initiation within a short range, a flame focusing structure with a shock wave focusing flame was designed, and the flow field inside the structure was studied by numerical simulation. Results showed that the acceleration region was an important region for the acceleration of flame instability, and the local energy explosion caused by the energy convergence in the focusing region was the key factor for the acceleration of deflagration to detonation transition. In this region, the vortex induced by the geometrical structure can enhance the focusing and hinder the shock wave back into the accelerating region. The transition region of the detonation wave from the over driving state to the stable detonation state was mainly realized in the stable region.The temperature and pressure fluctuations on the central axis were caused by the focusing action of the focusing cavity, and the temperature and pressure changes of the detonation front were caused by the three wave point motions.