FLOW AT LOW-CRESTED STRUCTURES UNDER BREAKING CONDITIONS

摘要

An analysis of the near-fiel flow at rubble-mound low-crested structures under breaking conditions is conducted using a VOF-type numerical model named COBRAS, based on the Reynolds-Averaged Navier Stokes (RANS) equations and including a nonlinear k-? model. The numerical model is validated using experimental data of free surface motion and bottom pressure from large-scale laboratory tests. The numerical results compare well with the corresponding measurements. The model is able to reproduce adequately the processes of wave interaction with the permeable structure, in particular partial reflection and energy dissipation by breaking and internal friction. The numerical results are used to further explore the breaking-induced flow conditions at the breakwater. The potentiality of the numerical model for assessment of LCS functional design is outlined.