铝药型罩环形聚能射流的数值模拟

Numerical Simulation of Annular Shaped Charge with Al Liner

基于一种药型罩材料为铝的环形聚能装药结构,通过Autodyn软件模拟不同起爆方式(起爆环直径D1)和不同长径比(L/D)的装药,计算得到环形射流的成型过程和速度分布曲线.分析数值模拟结果发现:环形射流成型过程主要受长径比影响,长径比较小时射流发生内偏,长径比较大时射流发生外偏;射流轴向速度主要受长径比影响,长径比越大轴向速度越大,头部轴向速度最大相差约700 m/s;射流径向速度主要受起爆方式影响,平均径向速度最大相差为220 m/s,起爆环直径和长径比在较小或较大时,射流径向速度梯度较大;结合射流成型和速度结果,D1=0.5D、L/D=1.0时射流综合性能较好.侵彻混凝土板试验的通孔直径为装药直径的2.6倍,数值模拟结果与试验结果误差为7.7%,验证了计算模型及算法的合理性.

Based on an annular shaped charge with aluminum liner, different modes of initiation(initiation radius D1) and length-to-diameter ratio(L/D) were simulated by Autodyn to measure the formation and jet speed of the annular jet. Numerical results showed that the formation process of the annular jet was mainly influenced by L/D, the jet tip had an inward deflection when L/D was relatively small, and an outward deflection otherwise. The axial jet speed was positively related to and also mainly influenced by L/D, and the maximum difference was about 700 m/s. The radial jet speed was mainly influenced by modes of initiation, and the maximum radial jet speed difference was about 220 m/s. The radial jet speed gradient was greater when D1 or L/D was relatively small or big. Combined with jet formation and speed, D1=0.5D and L/D=1.0 were preferred settings for this charge. The hole diameter of the concrete target was 2.6D1, which is 7.7% bigger than the numerical result. The penetration experiment demonstrates that the calculation model and method are appropriate.