Modelling of wave overtopping at dikes using openfoam

The average overtopping discharge is an important parameter for the design of flood defences. Several empirical formulas are available forpredictingthe overtopping discharge at dikes. However, these empirical formulas often have their specific applicable conditions. To complement withthe empirical methods, a numerical model has been developed using the open source CFD package OpenFOAMto model the wave overtopping at dikes. Systematic calibration and validation of the numerical model areperformed. The influencesof the mesh, solver, turbulence model and roughness height on the modelled results of the average overtopping discharge havebeen investigated during the model calibration. The simulations show that the turbulence model increasesthe accuracy of the numerical model for predicting the average overtopping discharge under wave breakingconditions.The calibrated model is then validated by comparing the modelled average overtopping dischargeswith the measured ones from the physical model tests. Results show that the OpenFOAM model is capable of predicting the average overtopping discharge accurately at dikes that have a smooth straight waterside slope.