高功率微波土壤击穿的数值验证研究∗

摘要

The nonlinear changes of soil resistivity will be caused when the high power microwave (HPM) propagates in soil, and these changes in turn counteract the propagation process so that the energy transmission efficiency of the HPM is reduced. By analyzing the dynamic ionization process of soil, a HPM soil propagation model is constructed by combining the Maxwell equations. The model is numerically validated by using a finite difference time domain method. The numerical results show the physical processes of the HPM propagation and attenuation in soil and the nonlinear change process of soil resistivity. These numerical results are verified by a theoretical analysis.%高功率微波在土壤中传播时，会引起土壤击穿电离而导致土壤电阻率的非线性变化，土壤电阻率的变化又将反作用于传播过程，加剧高功率微波衰减，影响其能量传输效率。通过对土壤动态电离过程的分析，结合Maxwell方程组构建了高功率微波土壤传播模型，采用时域有限差分法对该模型进行数值验证。数值结果显示了高功率微波在土壤中传播、衰减等物理图像，以及土壤电阻率的非线性变化过程。理论分析验证了这些数值结果。