电缆X射线辐射感应电导率引起的非线性效应

摘要

Nonlinear response of cable irradiated by X-ray is simulated using numerical method.The physical processes of the X-ray irradiating to cable are analyzed.Norton-equivalent driver model is built up for coaxial cable or shielded multi-cable based on 2-dimension finite-element method,focusing on dielectric’s radiation-induced conductivity effect.The nonlinear respon-ses of Norton-equivalent driver are calculated and their regularities are concluded in detail.The simulation result showed that the current amplitude would reach a saturation value as the X-ray fluence increased when induced conductivity existed.For some types of cable,there would be 3 different current peaks appearing successively at different point on the waveform while the X-ray fluence increased.%对电缆 X 射线辐照非线性响应进行了数值模拟。分析了电缆 X 射线辐照的物理过程，针对同轴电缆和屏蔽多导体电缆，建立了基于有限元方法的二维电缆模型诺顿等效电流源计算方法，着重描述了二维模型下电缆介质辐射感应电导率效应求解方法，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非线性响应规律，并依据物理过程进行了合理性分析。模拟结果显示，由于辐射感应电导率的存在，随着 X 射线注量的增加，电缆响应幅度会存在明显的饱和现象。对特定类型的电缆，响应电流随着 X 射线注量增加，依次出现3个时间位置不同的电流峰值。