土中弹道的试验与数值模拟研究

弹丸在侵彻自然土壤过程中很容易产生弹道失稳现象,对弹丸的侵彻与毁伤目的造成很大的影响,因此,分析弹丸侵彻自然土壤的弹道特性是十分重要的。本文通过56式枪弹和125mm弹侵彻自然土壤的试验,得到了弹丸侵彻土壤的弹道轨迹图像,并对其进行了分析研究。其中发现弹丸侵彻自然土壤时,会迅速失去姿态稳定,在土壤中产生较大空腔,并增加与土壤的接触面积,增大阻力,使弹丸速度迅速降低,影响弹丸的侵彻深度。同时,根据试验条件,利用LS-DYNA建立了计算仿真模型,获得了弹丸在侵彻过程中的姿态和运动特征。计算获得的弹丸姿态与弹道特征与试验图像比较吻合,对弹丸的速度、位移和负加速度做了分析研究,表明数值计算结果具有较高的可靠性,可以为弹丸侵彻土壤研究提供参考。

Study on experimental and numerical simulation of soil ballistic

The projectile in the process of penetration of the soil is easy to generate ballistic instability phenomenon, which has considerable influence on the projectile penetration and damage. Therefore, it is very important to analyze the ballistic characteristics of projectiles penetrating into natural soil. In this paper, the ballistic trajectory images of projectiles penetrating into soil were obtained by experiments of 56 bullets and 125mm projectiles penetrating into the soil and making analysis to them. It was found that when the projectiles penetrated the natural soil, it would quickly lose its attitude stability, create a large cavity, increase the contact area with the soil and the resistance. These would have a great impact on the penetration depth of the projectile. At the same time, according to the experimental conditions, a computational simulation model was established by using LS-DYNA, and the attitude and motion characteristics of the projectile during penetration were obtained. The calculated attitude and ballistic characteristics of the projectile are in good agreement with the experimental image. The velocity, displacement and negative acceleration of the projectile were analyzed and studied. The results show that the numerical results have higher reliability and can provide reference for the penetration of projectiles into soil.