CFD Investigations of Interaction Between Freak Wave and Bottom-Mounted Vertical Cylinder

We studied the interactions between freak wave and bottom-mounted vertical cylinder. The freak wave is generated through linear superposition method which satisfies the definition that the wave height is at least two times the significant wave height. A numerical wave tank is developed based on FLUENT software in which the finite volume method is used for the spatial discretization. Grid sensitivity is conducted in 2D model, and then the freak wave is simulated in 3D model. The freak wave loads on the vertical cylinder are calculated and compared with the results obtained through Morison equation. The numerical results present larger peak and shallower trough compared with the prediction of Morison equation. Meanwhile, the free surface wave elevation within a radius distance around the vertical cylinder is investigated. The lowest wave run-up around vertical cylinder caused by freak wave is about 55% of the highest wave run-up, and the direction is about 45° of the wave propagation. © 2022, Shanghai Jiao Tong University.