破片防护结构对冲击波测试影响的数值分析

Numerical Analysis of Influence of Fragment Protection Structure on Shock Wave Test

针对防护结构对冲击波特征的影响,利用AUTODYN对防护结构条件下冲击波信号传播进行数值模拟。采用2D-Euler Multi-material算法进行仿真计算,将防护区域不同位置冲击波压力曲线、特征参数与空旷环境进行对比,分析防护结构与测点的距离及防护结构偏离冲击波传播方向的角度α对冲击波测试的影响。结果表明:在单向防护时,若达到正向防护(α=0)且防护结构与测点距离等于10倍圆柱直径时,压力峰值、正压作用时间和比冲量误差分别为0.51%、4.36%和1.91%;在多向防护时,以10倍直径距离分析,α=0时,压力峰值误差最小,为-0.43%;α=30°时,正压作用时间和比冲量误差更小,为-2.91%和0.66%。

Aiming at the influence of protective structure on shock wave characteristics,numerical simulation of shock wave signal propagation under the condition of protective structure is carried out by using AUTODYN.The 2D-Euler Multi-material algorithm was used to simulate and calculate,and the shock wave pressure curves and characteristic parameters at different locations in the protected area were compared with those in the open environment,and the effects of the distance between the protected structure and the measuring point and the angle α of the protected structure deviating from the propagation direction of the shock wave on the shock wave test were analyzed.The results show that the errors of peak pressure,positive pressure action time and specific impulse are 0.51%,4.36%and 1.91%respectively when the distance between the protective structure and the measuring point is 10 times of the cylinder diameter and the positive protection is achieved(α=0)in one-way protection;In the case of multi-directional protection,the error of peak pressure is the smallest,which is-0.43%,when α=0,and the error of positive pressure action time and specific impulse is even smaller,which is-2.91%and 0.66%,when α=30°.