电控固体推进剂点火技术研究

采用一种层状电极式点火装置,分别研究了电极材料、电极形状和电极极性对电控固体推进剂点火过程的影响。试验结果表明,电极材料、推进剂端面电流密度和电极极性是影响电控固体推进剂点火过程的重要因素,当推进剂两端面电流密度相同时,采用不同材料的电极优先点火顺序依次为钛、铝、石墨、铜。当两端电极材料相同时,ESP始终在电流密度较大的一端点火,且电流密度越大,点火效果越好,临界点火电压越低;当两电极与药柱端面的接触面积比为1∶1和0.64∶1时,ESP优先在正极端点火;但当两电极与药柱端面的接触面积比为0.16∶1时,ESP在电流密度较大的一端点火。电控固体推进剂能通过电压控制实现多次点火、熄火循环。

Experimental investigation of electrically stimulated ignition characteristics of electric solid propellant

Electric Solid Propellants (ESP)are capable of multiple ignitions, extinguishments and throttle control by the appli-cation of electrical power. When an ESP is fitted with electrodes and the required voltage are applied, the solid propellant was igni-ted and continues to burn until the voltage is removed, causing extinguishment. In this work, we developed an end-burner with lay-ered electrodes to investigate the ignition characteristics of electric solid propellants at ambient pressure. Testing results indicated that electrode material, current density, electrode polarity are the mainly factors that influence the ignition characters of ESP. The ignition preferentially occurs on the active surface of metal electrode. The initial ignition of ESP was taken place on the surface with larger current density using the same electrode material. The flame becomes more observable as the applied voltage increases. The ESP is preferentially ignited at the anode when the contact area ratio of the two electrodes to the ESP grain is 1 : 1 and 0.64 : 1, but when the contact area ratio of two electrodes to ESP grain is 0.16 : 1, ESP could be ignited on the surface with higher current density.