© 2023 by the authors. Licensee MDPI, Basel, Switzerland.Ruiz Cabello Núñez, M. D.Martín Valverde, A. J.Plaza Gallardo, B.Frövel, M.Poyatos Martínez, D.Rubio Bretones, Amelia C.Gascón Bravo, AlbertoGarcía, S. G.2024-02-262024-02-262023-08-03Applied Sciences 13(15): 8949(2023)https://www.mdpi.com/2076-3417/13/15/8949http://hdl.handle.net/20.500.12666/945(This article belongs to the Special Issue Feature Papers in 'Electrical, Electronics and Communications Engineering' Section). Ruiz Cabello, M. [0000-0001-9039-6181]; Martín Valverde, J. [0000-0003-1417-1268]; Plaza Gallardo, B. [0000-0003-3615-0353]; Frövel, M. [0000-0001-9447-4036]; Poyatos Martínez, D. [0000-0002-3829-5110] ; Rubio Bretones, A. [0000-0002-9337-9093] ; Gascón Bravo, A. [0000-0003-1190-2248] ; García García, S. [0000-0003-4494-7565].Efficiently modeling thin features using the finite-difference time-domain (FDTD) method involves a considerable reduction in the spatial mesh size. However, in real-world scenarios, such reductions can lead to unaffordable memory and CPU requirements. In this manuscript, we present two stable and efficient techniques in FDTD to handle narrow apertures on conductive thin panels. One technique employs conformal methods, while the other utilizes subgridding methods. We validate their performance compared to the classical Gilbert-Holland model and present experimental results in reverberation environments to shed light on these models’ actual confidence margins in real electromagnetic compatibility (EMC) scenarios.engAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttps://creativecommons.org/licenses/by-nc-nd/4.0/Numerical electromagneticsComplex electromagnetic environmentsElectromagnetic compatibilityFinite difference time domain (FDTD)Narrow slotSmall aperturesSubcell modelingSubgriddingThin gapsinfo:eu-repo/semantics/article10.3390/app131589492076-3417info:eu-repo/semantics/openAccess