温压炸药自由场爆炸空气冲击波的数值模拟研究

摘要

基于二次反应理论,采用AUTODYN程序对温压炸药(RDX/AWAL/粘合剂=20/43/25/12)自由场爆炸空气冲击波进行了数值模拟研究.得出结论:在比例距离1～8m/kg1/3内,铝粉后燃反应对超压峰值的贡献约为24％～31％,对正超压区冲量的贡献约为31％～39％,对正超压区持续时间的贡献约为12％ ～95％,且在爆炸近区,正超压区持续时间明显增加；相对于传统高能炸药TNT,由于后燃反应的影响,温压炸药爆炸冲击波超压衰减较慢,具有更高的正压区冲量,具有相对较长的正压区持续时间.根据数值结果,最小二乘拟舍得到了温压炸药自由场爆炸空气冲击波超压峰值随比例距离衰减的公式,可用于预估其自由场爆炸空气冲击波超压峰值.%Based on the secondary reaction theory,the airblast of thermobaric explosive (RDX/AP/AL/adhesive = 20/43/25/12) explosion in free air are numerically simulated by AUTODYN. The conclusions are that the contribution of aluminum powder afterburning reaction to peak overpressure,positive overpressure impulse and positive overpressure duration are 24%~31% ,31%~39% and 12%~95% respectively in scaled distance of 1~8 m/kg1/3, and the positive overpressure has relatively longer duration near explosion zone, and comparing with traditionally high explosive TNT,thermobaric explosive has slower overpressure decay rate,higher impulse,and longer overpressure duration. Based on numerical calculation results,the formula for predicting peak overpressure attenuation of the thermobaric explosive with scale distance in free is obtained with the least squares fitting.