屏蔽电缆X射线辐照非线性效应模拟

Simulation of Nonlinear Effect of Shielded Cable Irradiated by X-ray

本文分析了X射线辐照电缆的物理过程,建立了电缆介质层辐射感应电导率(RIC)和间隙效应计算模型,采用有限元方法模拟了电缆X射线辐照非线性效应,给出了诺顿等效电流源(NCD)的非线性响应规律。模拟结果表明,仅考虑RIC效应时,随着X射线注量的增加,NCD幅度存在明显的饱和现象,波形宽度逐渐变窄;仅考虑间隙效应时,NCD幅度近似正比于间隙宽度;当同时考虑两种效应时,间隙效应将会大幅抵消RIC对NCD的影响。因此,在预估核爆环境下屏蔽电缆的X射线辐照响应时,需综合考虑RIC和间隙非线性效应的影响。

The physical processes of X-ray irradiating cable were analyzed in this paper. The calculation models of dielectric＇ s radiation-induced conductivity （RIC） and gap effects were built up. The two-dimensional finite-element method was employed to sim- ulate the nonlinear effect and the nonlinear regularity of the Norton-equivalent current driver （NCD） was concluded in detail. The simulation results show that the NCD＇s amplitude tends to be saturated and its pulse width tends to be narrower with the increase of X-ray fluence when the RIC effect exists only. The NCD＇s amplitude is in direct proportion to the gap width when the gap effect exists only. Meanwhile, the gap effect can counteract the RIC effect greatly when both effects are considered. Therefore, nonlinear effect caused by both effects should be taken into account for the predication of cable＇s responses under nuclear explosion X-ray.