3种典型炸药水中爆炸初始冲击波的近场参数测试

Test Research about Close-field Parameters of Original Shock Wave for Three Typical Explosives by Underwater Explosion

为了探索水中爆炸初始冲击波近场的传播特性和衰减差异,扩展水箱法测爆压试验的研究范围,采用高速摄影狭缝扫描测试方法,对3种典型的柱状炸药(TNT、JH-14、JO-9159)水中爆炸过程进行了测试研究,测量获得了一维正平面水中初始冲击波传播的时间历程演化曲线;由此拟合计算出柱状炸药的水中初始冲击波传播速度随时间的变化曲线,进一步由水的冲击雨果尼奥方程和冲击波动量方程、界面上压力和质点速度连续的条件及声学近似理论,计算得到了水中爆炸初始冲击波阵面压力的衰减曲线和炸药试样的爆压、多方指数等爆轰参数。结果表明,水中爆炸初始冲击波阵面压力近似以指数形式衰减,初始阶段衰减极快;当炸药爆压为20~37 GPa时,水中冲击波初始速度处于5.66~6.81 km/s的范围,波阵面初始压力与炸药的爆压近似成线性关系;虽然JO-9159的爆速和爆压均高于JH-14和TNT,但其水中初始冲击波传播仅在7μs后,其冲击波速度与波阵面压力下降至最低,说明以HMX为基的理想炸药水中爆炸初始冲击波速度和波阵面压力的衰减率要高于以RDX为基的理想炸药和TNT,高爆速、高爆压类理想炸药在水中初始冲击波性能方面优势不显著。

In order to explore the propagation characteristics and attenuation differences of the initial shock wave in the close field of an underwater explosion and extend the application of the detonation pressure test by water tank,underwater explosions of three typical cylindrical explosives(TNT,JH-14,JO-9159)were tested by the streak record of high-speed photography.The evolution curve of the one-dimensional positive planar initial shock wave was recorded and was fitted to obtain the velocity-time curve of the underwater initial shock wave.Furthermore,the pressure attenuation curve of the initial shock wave front during the underwater explosion and the detonation parameters,including detonation pressure,multiplicative index,et al.,were calculated by the Hugoniot equation of water,the momentum equation of the shock wave,the continuous equation of interface pressure and velocity,and the approximate theory of acoustics.The results show that the pressure of the initial shock front decreases approximately in index form during the underwater explosion and decreases extremely quickly in the initial stage.When the detonation pressure and the initial velocity of the shock wave are in ranges of 20—37 GPa and 5.66—6.81 km/s,respectively,the pressure of the shock wave front is approximately linearly related to the detonation pressure.Although the detonation velocity and detonation pressure of JO-9159 are higher than those of JH-14 and TNT,the shock wave velocity and shock front pressure of JO-9159 decline to the minimum after an only-7μs propagation of the initial shock wave in water.Hence,during the underwater explosion,the velocity of the initial shock wave and the attenuation rate of the wave front pressure of the ideal explosives based on HMX are higher than those based on RDX and TNT.Namely,there are no remarkable benefits to the initial shock wave performance of the ideal explosives with high detonation velocity and pressure in water.