Calculations of Wave Loads on a Vertical Cylinder Using Potential-Flow and Viscous-Flow Solvers

In this paper, potential-flow and viscous-flow (CFD) solvers are used to compute wave loads on a suspended surface piercing cylinder, for a Keulegan-Carpenter number of KC ≈ 5. After describing the numerical tools used (Wavec2Wire and Re-FRESCO), and the associated numerical settings, a calibration of the wave height and periods is made with basis on experimental data. On the viscous-flow CFD side, attention is also paid to discretization (space and time) and iterative errors, in order to keep the uncertainty of the calculations the lowest possible. Moreover, both a non-turbulent symmetric domain and a turbulent full domain CFD calculations are performed and compared. On the potential-flow side, calculations with and without considering additional-drag forces of the cylinder are conducted. In general, the comparison between potential and viscous-flow results show small differences, with a slightly better agreement between the viscous-flow results and experiments but with a significant increase on computational costs. For this particular case the consideration of turbulence and of additional-drag forces have negligible influence on the results obtained.