Purpose

This paper aims to explore the limitations of the conformal finite difference time-domain method (C-FDTD or Dey–Mittra) when modeling perfect electric conducting (PEC) and lossless dielectric curved surfaces in coarse meshes. The C-FDTD is a widely known approach to reduce error of curved surfaces in the FDTD method. However, its performance limitations are not broadly described in the literature, which are explored as a novelty in this paper.

Design/methodology/approach

This paper explores the C-FDTD method applied on field scattering simulations of two curved surfaces, a dielectric and a PEC sphere, through the frequency range from 0.8 to 10 GHz. For each sphere, the mesh was progressively impoverished to evaluate the accuracy drop and performance limitations of the C-FDTD with the mesh impoverishment, along with the wideband frequency range described.

Findings

This paper shows and quantifies the C-FDTD method’s accuracy drops as the mesh is impoverished, reducing C-FDTD’s performance. It is also shown how the performance drops differently according to the frequency of interest.

Practical implications

With this study, coarse meshes, with smaller execution time and reduced memory usage, can be further explored reliably accounting the desired accuracy, enabling a better trade-off between accuracy and computational effort.

Originality/value

This paper quantifies the limitations of the C-FDTD in coarse meshes in a wideband manner, which brings a broader and newer insight upon C-FDTD’s limitations in coarse meshes or relatively small objects in electromagnetic simulation.

中文翻译：

---

C-FDTD在曲面离散化贫困中的宽带性能限制

目的

本文旨在探索在粗糙网格中建模完美导电（PEC）和无损介电曲面时，共形有限差分时域方法（C-FDTD或Dey-Mittra）的局限性。C-FDTD是减少FDTD方法中曲面误差的一种众所周知的方法。但是，其性能局限性在文献中并未得到广泛描述，本文将其作为一种新颖性加以探讨。

设计/方法/方法

本文探讨了C-FDTD方法在频率范围为0.8至10 GHz的两个曲面（电介质和PEC球）的场散射模拟中的应用。对于每个球体，网格都会逐渐变薄，以评估C-FDTD的精度下降和性能限制以及网格变差以及所描述的宽带频率范围。

发现

本文显示并量化了C-FDTD方法由于网格贫乏而导致的精度下降，从而降低了C-FDTD的性能。还显示了性能如何根据感兴趣的频率而有所不同。

实际影响

通过这项研究，可以进一步探索具有更短执行时间和更少内存使用量的粗网格，从而可靠地计算出所需的精度，从而在精度和计算工作量之间取得更好的折衷。

创意/价值

本文以宽带方式量化了C-FDTD在粗网格中的局限性，这为C-FDTD在电磁仿真中在粗网格或相对较小物体中的局限性提供了更广泛和更新的见解。