Numerical modeling for studying tidal inlets stability

The present study investigates the possibility of designing a stable tidal inlet with self flushing and stable channel using a numerical model. The numerical model is developed and verified to simulate the flow and sediment motion in tidal inlet under the effect of tides and fresh water discharge to the lagoon. The program has two main parts; hydrodynamics and sedimentation. With the help of the developed program and based on the stability criteria, the design of stable inlet is presented. The hydrodynamic part is used to estimate velocities, discharge, tidal prism, Kelugan coefficient and lagoon/bay water level as a function of inlet geometry, tide type and tidal range in the sea. The sedimentation part is used to compute the sediment transport into the channel based on the current field from the hydrodynamic part at each time step. The field data, collected for the two inlets of El-Bardawil lagoon were used to calibrate the model. The model was used to evaluate the present two inlets and also used to design a new stable inlet for this lagoon. The model has proven its capability in designing stable inlets with depths that can allow the trapping of sediment until it is flushed out.