The traditional finite-difference time-domain (FDTD) method is constrained by the Courant–Friedrich–Levy condition and suffers from the notorious staircase error in electromagnetic simulations. This article proposes a 3-D 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 locally one-dimensional FDTD (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 Neumann method. Significant gains in central processing unit time are achieved by using large time steps without sacrificing accuracy. Two numerical examples, including 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 that the CLOD-FDTD method shows better accuracy and can improve the efficiency compared with those of the traditional FDTD method and the traditional LOD-FDTD method.

中文翻译：

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弯曲PEC物体的无条件稳定共形LOD-FDTD方法及其在EMC问题中的应用


传统的时域有限差分 (FDTD) 方法受到 Courant-Friedrich-Levy 条件的约束，并且在电磁仿真中存在臭名昭著的阶梯误差。本文提出了一种 3-D 共形局部一维 FDTD (CLOD-FDTD) 方法来解决完美导电 (PEC) 物体建模的两个问题。通过考虑部分填充的单元，所提出的CLOD-FDTD方法与传统的局部一维FDTD（LOD-FDTD）方法和FDTD方法相比可以显着提高精度。同时，所提出的方法保持了无条件稳定性，并使用冯·诺依曼方法对其进行了分析和数值验证。通过使用大时间步长而不牺牲精度，可以显着提高中央处理单元的时间。使用两个数值示例（包括 PEC 圆柱体和导弹）来验证其在不同网格和时间步长下的准确性和效率。从这些例子可以看出，与传统FDTD方法和传统LOD-FDTD方法相比，CLOD-FDTD方法表现出更好的精度，并且能够提高效率。