目的 探究破片着靶距离对侵彻行为及破片剩余速度的影响规律，为多破片冲击条件下的防护材料优化设计提供理论依据。方法 利用有限元仿真方法，以单破片侵彻靶板行为为基础，研究不同形状破片的侵彻性能规律，并以2枚破片在10 mm间距内同时撞击目标为例，分析间距对目标抗穿透能力及破片侵彻行为的影响。结果 不同形状破片在10 mm间距内撞击目标时表现出显著的力学响应差异，其中圆柱体破片穿透能力最强。当2枚破片的间距<0.5~1倍弹径时，应力波叠加效应增强，导致靶板局部损伤加剧，形成集中破坏区域。结论 2枚破片近距离同时穿靶时剩余速度的变化是靶板变形、应力波叠加、流体动力学效应耦合作用的结果，可为破片侵彻性能评估及防护结构优化设计提供理论支持。

The work aims to explore the effect of fragment impact distance on the penetration behavior and fragment residual velocity to provide theoretical basis for the optimal design of protective materials under the condition of multi-fragment impact. By the finite element simulation method, based on the penetration behavior of a single fragment, the penetration performance of different shapes of fragments was studied, and the effect of the spacing on the penetration resistance and the penetration behavior of the target was analyzed with the example of two fragments impacting the target at the same distance of 10 mm. The mechanical responses of the fragments with different shapes were significantly different when they impacted the target at a distance of 10 mm, and the penetrating ability of the cylindrical fragment was the strongest. When the distance between the two fragments was less than 0.5-1 times the bullet diameter, the superposition effect of stress waves was enhanced, which led to the local damage of the target plate and the formation of a concentrated damage area. The variation of residual velocity when two fragments penetrate the target at a close distance at the same time is the result of the deformation of the target plate, the superposition of stress waves and the coupling effect of fluid dynamics. This study can provide theoretical support for the evaluation of fragment penetration performance and the optimal design of the protective structure.