管道内高温火团诱导H_2-O_2-N_2爆轰波传播特性研究

Study on propagation of high temperature flame-included hydrogen-oxygen-nitrogen mixture detonation wave in duct

为研究管道内H2-O2-N2爆炸特性,高温火团点火诱导的预混气体的爆轰形成过程及其流场变化,基于改进的全耦合总变差下降格式和简化的基元化学反应模型,建立可燃预混气体爆轰波传播过程的二维数值模型,模拟H2-O2-N2爆轰形成和传播过程,以及初始混合气体积分数比、点火温度对爆轰传播的影响。结果表明,点火初期燃烧加速形成的爆轰波发生反射,反射波不断向前移动。高温火团初始温度和压力越高,H2-O2-N2混合气燃烧加速形成爆轰所需的诱导时间越短;初始混合气中氢气与氧气的体积分数比接近2时,其爆轰波传播速度更快,波后压力更高。

To figure out detonation characters of gas in duct, we studied gas detonation ignition and flow field of prefixed hydrogen-oxygen-nitrogen mixture. A two dimensional model of detonation was developed by modified global coupling with TVD scheme. It was used to simulate gas detonation ignition, propagation and effect of propagation on volume fraction and ignition temperature. The results show that, in initial stage, detonation wave propagated and reflected along tube. The higher initial temperature of hot gas pock- et was, the shorter induction time of detonation. However, it has almost no influence on travel of detona- tion wave. When initial premixed mixture of equivalent ratio was two, a higher detonation speed and deto- nation pressure can be reached.