Abstract
Wave propagation over variable bathymetry is known as one of the possible mechanisms that can provoke rogue waves. In this paper, we use a fully nonlinear potential-flow solver, Ocean-Wave3D, to simulate the process of waves propagating over variable bathymetry and analyse the kinematics under the free surface near the top of the slope. To achieve this, we first evaluate the accuracy of the numerical results generated by Ocean-Wave3D. We carry out convergence tests to examine the influence of different parameters in OceanWave3D on the numerical results. Based on verification and validation tests, we evaluate the accuracy of OceanWave3D for problems with variable bathymetry comparing numerical and experimental results. We find that OceanWave3D is accurate enough to solve equations for problems with abrupt depth transitions and the agreement between experimental results and numerical results is good. Finally, we investigate the kinematics and we find that a slope can not only amplify crest amplitudes but also increase the wave kinematics near the top of the slope, which has obvious implications for loads on offshore structures.
