圆柱形带壳推进剂装药枪击响应特性

为研究某圆柱形带壳推进剂装药的枪击响应特性,设计了一种12.7 mm子弹撞击试验。利用高速摄影机记录带壳装药在子弹撞击下的响应过程,并测试不同距离、方位处的空气超压及壳体破片速度,同时进行带壳装药在理想爆轰条件下的数值计算,得到了带壳装药的能量释放率。一共开展了四次圆柱形带壳装药的枪击试验,前三次装药发生了爆燃反应,第四次几乎无反应。结果表明:子弹撞击位置对圆柱形带壳装药的反应和能量释放率有较大影响,当子弹垂直入射带壳装药轴线后,推进剂发生点火、冒烟、熄火和低压燃烧的时序响应,其相对能量释放率为1.146%;而当子弹撞击位置偏离轴线一定距离时,推进剂几乎无反应,其相对能量释放率仅为0.473%;推进剂的反应对壳体破片有加速效应,带壳装药发生爆燃反应时的破片速度可达428.6 m·s~(-1),而几乎无反应时的最高破片速度仅有70.1 m·s~(-1)。

Response Characteristics of Cylindrical Shelled Propellant Charges Under Bullet Impact

In order to study the response characteristics of cylindrical shelled propellant charges under the impact of the bullet, a kind of 12.7 mm bullet impact test was designed. The high-speed camera recorded the response of the shelled charges under the impact of a 12.7 mm bullet. Shell fragment velocities and air overpressures at different positions and azimuths were measured. Besides, the ideal detonation of the shelled charge was numerically calculated and the relative energy release rate was obtained. Four bullet impact tests of cylindrical shelled charge were carried out totally, in the first three tests, deflagration reaction occurred in the charge, and in the fourth test, almost no reaction occurred in the charge. Results show that the reaction and relative energy release rate are great influenced by the impact position. A time sequence response of ignition, smoking, extinguishment and low-pressure combustion occurred in the propellant when the bullet impacted vertically on the axis of the shelled charge, and its relative energy release rate was 1.146%. When the bullet impact position deviated from the axis by a distance, the propellant almost had no reaction, and its relative energy release rate was only 0.473%. The reaction of propellant can accelerate the shell fragments. When the deflagration reaction occurred in the shelled charge, the fragment velocity could reach 428.6 m·s^-1, while the maximum fragment velocity was only 70.1 m·s^-1 when the propellant almost had no reaction.