The effect of heave-face plates on FOWT heave motion: Fluid dynamic analysis

Renewable energy technology is a topic that has often been raised in many studies lately. To support the 2020-2024 PRN (National Research Priority) program in the Maritime sector, the Researcher has developed FOWT (Floating Offshore Wind Turbine), a Classic SPAR design to operate and serve the eastern Indonesia region. A novelty design, namely the "Motion Reduction Device" (MRD), is installed at the bottom of the FOWT floater intended to increase its natural period and reduce heaving and pitching motion when exposed to environmental loads. The ANSYS FLUENT Computational Fluid Dynamics (CFD) simulation of heave decay is applied to calculate natural periods for several MRD types. A mesh convergence study was carried out to determine the best mesh size. The damping terms are derived by matching the heave motion obtained using the equation of motion by changing the damping time with linear, quadratic, or a combination of linear and quadratic. The added mass and damping results are then plotted in a graph and table. It has been demonstrated that MRD has a more significant impact than simply installing a heave plate at the bottom of the FOWT by significantly increasing added mass and damping.