固体火箭推进剂的模拟低温点火冲击试验加载方法研究

固体火箭推进剂低温下点火瞬间高速加载的耦合作用可能会导致推进剂结构发生破坏，针对此问题，利用推进剂中止熄火的原理，设计了一种中止压力可控模拟点火冲击试验装置，以点火药燃烧产生的燃气对推进剂进行模拟点火冲击。点火压力根据药室容积和点火药量之间的计算公式确定，中止压力通过爆破片破片压力控制。通过对点火冲击过程的压力与时间和升压速率与时间关系曲线分析，得知点火压力和点火方式对点火药燃气的升压速率影响较大。多次重复试验表明：该加载方法中止压力可控，压力偏差<±5%；弱点火时升压速率为2 000 MPa/s，强点火时升压速率达到5 000 MPa/s， 高于通常发动机点火的升压速率；可作为固体火箭推进剂模拟低温点火冲击的研究手段。

Research on Loading Method of Simulation Ignition Shock Testing for Solid Rocket Propellant at Low Temperature

A simulation ignition shock test device with controllable pressure is designed using propellant quenched combustion experimental principle to deal with the structure failure problem of solid propellant at low temperature,which can be caused by the coupling effect of high speed loading.The simulation ignition shock against propellant is made by the gas produced from the combustion of ignition material.The ignition pressure is calculated using the formula of chamber volume and weight of ignition material,and the quenched pressure is controlled by rupture disc.The ignition pressure and ignition mode have great influence on the gas pressurization rate according to p-t and dp/dt-t curves of the ignition shock process.Pressurization rate can be up to 2 000 MPa/s in weak ignition case and 5 000 MPa/s in strong ignition case,which is higher than real motor ignition rate.The pressure is controllable (the pressure deviation is less than ± 5％) in repeated experiments.The testing is expected to be used to simulate the ignition shock process for solid propellant at low temperature.