基于CFD高精度算法的雷电电磁场研究

雷电空间电磁场一直是电磁领域研究的热门，成熟的算法例如有限时域差分法（FDTD），传输线矩阵法（TLM）以及频域的矩量法（MoM）在计算雷电问题方面都有广泛的应用。由于计算流体力学（CFD）中的Euler方程与电磁学中的Maxwell方程有着相同的守恒形式，而且采用间断伽辽金方法（DG）已经在流场问题上得到广泛的尝试，因此引入了基于计算流体力学的DG方法来离散时域Maxwell方程，并采用网格分区并行技术加速计算，使用基于DG的圆球雷达散射截面积（RCS）算例进行测试，数值结果一致表明DG算法在求解电磁场问题上的可行性，之后通过计算一段近场雷电通道的电场分布并与解析解、某算法仿真解对比，数据基本吻合，说明该方法适合于雷电电磁场的计算。

Research on lightning electromagnetic field based on CFD high-precision algorithm

Lightning space electromagnetic field has always been a hot topic in the electromagnetic field. Mature algorithms such as the Finite-Difference Time-Domain (FDTD), Transmission-Line Modeling (TLM) and frequency domain Method of Moments (MoM) have a wide range of applications in computing lightning problems. Since the Euler equation in Computational Fluid Dynamics (CFD) and the Maxwell equation in electromagnetics have the same conservation form and the Discontinuous Galerkin (DG) method has been widely tried in the flow field problem, a DG method based on CFD is proposed to discretize the time domain Maxwell equation. The grid partition parallel technology is used to accelerate the calculation, and the DG-based spherical RCS example is used for testing. The numerical results show the feasibility of the DG algorithm in solving the electromagnetic field problem. Calculation results of the electric field distribution in a near-field lightning channel are compared with those using the analytical solution and the simulation solution of a certain algorithm. The data basically agrees, showing that the method proposed is applicable for calculation of lightning electromagnetic field.