RDX聚光点火和反应过程的光学诊断

Optical Diagnosis of RDX Condensing Ignition and Reaction Process

为拓展含能材料在聚光加热下点火和燃烧特性的实验方法,探究了燃烧反应过程中的物种变化及化学反应,基于聚光点火平台,采用高速摄影、化学发光、激光诱导荧光的方法,研究了聚光点火前后RDX反应的自发光过程、NO化学发光信号变化和RDX火焰内部OH自由基的二维浓度分布。结果表明,RDX聚光点火和反应过程分为4个阶段,分别为吸热、蒸发热解、点火和反应结束;整个反应过程的点火延迟时间为16.735s,燃烧持续时间为355ms,而高延迟的原因是由于聚光点火能量较低所致;NO化学发光显示,NO的产生存在明显的两阶段生成过程,且NO的生成受RDX蒸气和HCN、NO_(2)多种分解产物影响;OH的高浓度区主要分布于火焰的中部两翼,可由NO反应而产生。

In order to expand the experimental methods of the ignition and combustion characteristics of energetic materials under condensing ignition,the species changes and chemical reactions in the combustion reaction process were explored.Based on the condensing ignition platform,the self-luminescence process of RDX reaction,the change of NO chemiluminescence signal and the two-dimensional concentration distribution of OH radical in RDX flame before and after condensing ignition were studied by means of high-speed photography,chemiluminescence and laser-induced fluorescence.The results show that the RDX condensing ignition and reaction process is divided into four stages,which are endothermic,evaporative pyrolysis,ignition and end of reaction.The ignition delay time of the whole reaction process is 16.735s and the combustion duration is 355ms.The high delay is due to the low condensing ignition energy.The chemiluminescence of NO shows that there is an obvious two-stage process of NO production,and the production of NO is affected by RDX steam and various decomposition products like HCN and NO_(2).The high concentration area of OH is mainly distributed on the two wings of the flame middle,which can be produced by the reaction of NO.