| Title |
Quantifying the Impact of Rainfall Application (RoS vs. RoG) in Urban Flood Modelling: Joint Validation on Laboratory and Real Basins |
| Authors |
심상보(Sim, Sang Bo);김형준(Kim, Hyung-jun) |
| DOI |
https://doi.org/10.12652/Ksce.2025.45.6.0711 |
| Keywords |
도시홍수; 이중배수; 강우유출방식; 격자유출; 유역유출 Urban flood; Dual-drainage; Rainfall runoff-method; Rain-on-grid; Rain-on-subcatchment |
| Abstract |
This study quantitatively evaluates the accuracy and computational efficiency of two rainfall-runoff implementations?Rain-on-Subcatchment (RoS) and Rain-on-Grid (RoG)?using the coupled 1D-2D KICT-UF model to address urban flooding. Simulations were conducted on a laboratory catchment and a real urban basin (Sangpyeong District, Jinju) under identical boundary conditions. In the laboratory experiments, RoG consistently outperformed RoS, demonstrating superior reproducibility of peak flows and temporal variations; notably, RMSE decreased by approximately 57 % under 80 mm/h rainfall. Conversely, in the real urban basin, although RoG achieved a slightly higher spatial coincidence with observed inundation traces (81.1 %), it tended to overestimate the inundated area twofold due to simplified sewer inlet representations. Regarding efficiency, RoS was approximately 12 % faster than RoG. Consequently, RoG is recommended when high-fidelity topographic and network data are available, whereas RoS serves as an efficient alternative for rapid forecasting or scenarios with substantial data uncertainties. |