Modeling of fluid-structure interaction of a partially submerged human body

The significance of urban floods has heightened due to climate shifts, amplifying their adverse effects on human life across multiple domains, spanning injuries, fatalities, and structural collapses. It shows a growing need for human safety during floods. This dissertation evaluates human walking in flood conditions under different flow regimes using a 3D biomechanical multibody model. The dynamic interaction between floodwaters and the human body is analyzed through the use of the SWUMSUIT simulation tool. Utilizing information from an experimental model (developed by Postacchini et al. 2021), calibration procedures are taken into consideration for evaluating an appropriate drag coefficient, which influence the drag forces and power estimations. These calibrations are characterized by different Froude numbers. To assess propulsive efficiency, forces, and power on the submerged body parts in various conditions, real human gait data from Barela et al. (2006) were utilized in the SWUMSUIT numerical model. The results show a decline in the propulsive efficiency as the water depth increases. Notably, the swing phase is identified as a crucial phase in the stride cycle during which the lower extremities experience increased drag forces and increased power consumption, resulting in decreased efficiency. Moreover, the research emphasizes how vulnerable the swing phase is to increased fluid forces at deeper water depths. Shortening the swing phase or modifying body gait during walking in water is suggested to reduce the hazards related to greater forces in deeper water depths. Taking into account variables like age and gender, this approach could serves as a useful tool for comprehending gait behavior across various flow regimes. In conclusion, this research provides insights into human walking during floods, highlighting the role of the swing phase in decreasing efficiency. Incorporating GRF data for more accurate models and improving techniques to reduce the dangers related to fluid forces during water walking are potential future improvements.