Comparison of FLUMEN and HEC-RAS 2D Models for Flash Flood Inundation in Urban Landscape

Flood inundation maps play a crucial role in preventing flood damage. Among various numerical models used to generate these maps, the fluvial modeling engine (FLUMEN) and the hydrologic engineering center’s river analysis system (HEC-RAS 2D) are particularly effective for simulating urban floods, which are influenced by complex factors such as buildings and landscapes. This study aims to examine the differences in flood analysis results that may arise from using different numerical models. This study compares the performance of FLUMEN and HEC-RAS 2D in modeling urban flash floods, characterized by local velocity variations and complex geometries. The analysis focuses on their numerical characteristics and simulation accuracy. The simulation results show that HEC-RAS 2D outperforms FLUMEN in handling turbulence, numerical stability, and peak water level predictions. These findings provide insights into the strengths and limitations of each model for urban flood management.