薄片炸药与固体靶冲量耦合的计算模型

A computational model for impulse coupling between sheet explosive and target

薄片炸药可用于模拟强脉冲X射线辐照下空间结构的响应,其与固体靶的冲量耦合作用是进行模拟载荷设计的基础。本文中基于有限元模拟技术,研究不同直径薄片炸药的边界稀疏作用和安装支座的反射作用对薄片炸药与固体靶冲量耦合的影响,结果表明:边界稀疏作用对薄片炸药的比冲量起到减弱的作用,由边界稀疏作用引起的薄片炸药比冲量的变化量和薄片炸药直径的倒数近似成线性关系;薄片炸药安装支座的反射作用对薄片炸药的比冲量起到增强的作用,由支座反射作用引起的薄片炸药比冲量的变化量和薄片炸药直径的平方近似成反比;随着薄片炸药直径的增加,薄片炸药比冲量趋于定值,边界稀疏作用和支座反射作用可以忽略;存在一个临界直径,当薄片炸药的直径为临界直径时,薄片炸药的边界稀疏作用和支座反射作用达到平衡,其比冲量大小和薄片炸药的直径为无穷大时的比冲量值相等。

The sheet explosive can be used to simulate the space structure response caused by the high- power pulse X-rays, and the impulse coupling of the sheet explosive and the target is the basis for designing the simulated load. Based on the numerical results by the nonlinear finite element code, the computational modeling for the impulse coupling of the sheet explosive and the target is formulated in consideration of the effect on the specific impulse of the sheet explosive caused by the rarefaction of the border of the sheet explosive and the reflection of the support for connecting the mild detonating fuse and the sheet explosive. The analytic results reveal that the increment of the specific impulse caused by the rarefaction of the border is approximately in inverse relation to the diameter of the sheet explosive, and that caused by the reflection of the support is approximately in inverse relation to the square of the diameter of the sheet explosive. The specific impulse for the sheet explosive converges to the limit specific impulse related to the depth of the sheet explosive as the diameter of the sheet explo- sive reaches infinity. Both the rarefaction for the border of the sheet explosive and the reflection of the support are negligible with the diameter of the sheet explosive increasing. There exists a critical diam- eter and when it is equaled by the diameter of the sheet explosive, the specific impulse for the sheet explosive equals the limit specific impulse as the diameter of the sheet explosive reaches infinity.