SURFACE-GROUNDWATER FLOW NUMERICAL MODEL FOR COASTAL BARRIER BEACH
AbstractFine-grain beaches are relatively common where the beach forms part of a larger coastal barrier system. In such a coastal system, different water levels could be present in the seaward side and back-barrier lagoon. The water level changes in the steady-state lagoon may potentially induce groundwater dynamics near the beach which would subsequently affect seepage flow into (or out of) the beach. The exchange of water could generate varying hydrodynamical and morphodynamical behaviour at the seaward boundary. Hence, it is important to gain insight into groundwater flow dynamics which results in exchange of water between sea, barrier and lagoon; especially for coastal engineers responsible for planning and managing such a coastal environment. In present work, a numerical model is developed to simulate flows through a coastal barrier and it is validated against prototype-scale experimental results, which can then be extended to model small time-scale groundwater flows that may be too expensive or impractical to set up in a lab.
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