Some Benefits of High Pedestrian Density during Flood Evacuation

Flood evacuations often require walking through water, yet the impact of crowd density on pedestrian-water interactions remains understudied. This study uses 3D CFD simulations with the Volume of Fluid (VOF) method in Simcenter Star-CCM+ v2302 software to analyze hydrodynamic forces on pedestrians. Results show that higher crowd densities reduce individual drag and water resistance due to wake shielding effects, similar to hydrodynamic clustering. These findings can improve flood evacuation models and strategies to minimize individual energy expenditure in water.