Modelling flow in Estuarine urban Environment: Physical and Numerical modelling

Modelling flow in Estuarine urban Environment: Physical and Numerical modelling

Climate change is driving an increase in extreme weather events such as flash floods, droughts, and rising average sea levels across the globe. In recent years, the impact of urban flooding particularly from coastal floods has become increasingly significant due to more frequent intense storms and sea level rise. In such urban flood scenarios, studying how floodwaters interact with rigid structures and floating debris in complex and irregular urban layouts is critical for protecting pedestrians and evacuees during flood events. The danger escalates in narrow or sloped streets where floodwaters can surge, especially when moving debris becomes lodged against buildings, trees, or utility poles.

Simulating the interaction between moving objects and floodwaters in these constrained urban settings can help assess flow blockages, impact forces, and wave dynamics. Understanding these processes is essential to evaluate risks and design safer urban environments. Therefore, investigating the hydrodynamic behaviour in estuarine urban areas through both physical flume experiments and numerical modelling is crucial. This research supports the reassessment and potential redesign of existing infrastructure to better prepare for and reduce the effects of future urban flooding.

The core objective is to gain insight into how water flows through complex and irregular urban environments during flood event. This understanding is essential for identifying how floodwaters interact with various objects such as buildings, vehicles, and street infrastructure and for analysing the resulting hydrodynamic processes, including flow velocity, turbulence, water depth at various points, wave formation, and flow diversion patterns. Studying these interactions is particularly important in areas where narrow streets, elevation changes, and high building density influenced by flow behaviour.

The research methodology includes applying a shallow water equation solver to validate the results obtained from physical experiments. A scaled physical model, such as at a 1:20 ratio, will be developed to replicate an urban estuarine environment within a laboratory flume. Key urban features will be incorporated into this setup to simulate realistic coastal flood scenarios using controlled water inflow driven by wave-forcing mechanisms. To assess the interaction between water flow and objects, both rigid and floating objects will be introduced into the flume.