The traditional finite-difference time-domain (FDTD) method is constrained by the Courant-Friedrich-Levy (CFL) condition and suffers from the notorious staircase error in electromagnetic simulations. This paper proposes a three-dimensional conformal locally-one-dimensional FDTD (CLOD-FDTD) method to address the two issues for modeling perfectly electrical conducting (PEC) objects. By considering the partially filled cells, the proposed CLOD-FDTD method can significantly improve the accuracy compared with the traditional LOD-FDTD method and the FDTD method. At the same time, the proposed method preserves unconditional stability, which is analyzed and numerically validated using the Von-Neuman method. Significant gains in Central Processing Unit (CPU) time are achieved by using large time steps without sacrificing accuracy. Two numerical examples include a PEC cylinder and a missile are used to verify its accuracy and efficiency with different meshes and time steps. It can be found from these examples, the CLOD-FDTD method show better accuracy and can improve the efficiency compared with those of the traditional FDTD method and the traditional LOD-FDTD method.
翻译:传统的有限差异时间范围(FDTD)方法受到Curant-Friedrich-Levy(CFL)条件的限制,受到电磁模拟中臭名昭著的楼梯错误的影响,本文件建议采用三维的当地一维FDTD(CLOD-FDTD)方法,以解决完全电子操作(PEC)物体模型化的两个问题;考虑到部分填充的电池,提议的CLOD-FDTD方法可以大大提高与传统的LOD-FDTD方法和FDTD方法相比的准确性。同时,拟议的方法保持无条件稳定,使用Von-Neuman方法对它进行分析和数字验证。中央处理股(CPU)在使用大量时间步骤,而不牺牲准确性,从而取得重大进展。两个数字例子包括一个PEC圆筒,用一种导弹来核查其准确性和效率,不同中层和时间步骤。从这些例子中可以发现,CLODD-FDTD方法显示出更高的准确性,并且可以与传统的FDDD-D-LOD-TD方法相比,提高效率。