Author(s): Aristos Christou; Zhihua Xie
Linked Author(s): Zhihua Xie
Keywords: Fluid-Structure Interaction Large-Eddy Simulations Floating Structures Numerical Wave Tank
Abstract: The global effort towards sustainability to reduce the impact of climate change and global warming resulted in a rapid increase in the exploitation and utilization of offshore energy resources such as offshore wind, waves and tidal energy. In offshore environments, dominant wave conditions and wind currents result in strong and complex fluid-structure interactions in which offshore structures have to be designed and built to efficiently operate and function throughout the lifespan of the device. In this study, the in-house, open-sourced numerical wave tank based on the method of large-eddy simulations is employed to investigate the interaction of floating structures with realistic wave conditions to further understand the physics involved in such applications in an attempt to further improve existence and future designs. The three-dimensional code, hereafter referred to as Hydro3D-NWT, utilizes the method of large-eddy simulations coupled with the Level-Set method for multi-phase simulations and the Immersed Boundary method to simulate the effect of solid structures inside the flume. Inside the numerical tank, waves are generated using Dirichlet boundary conditions using analytical solutions of linear, non-linear, cnoidal, focused and solitary waves and absorbed near the outlet inside a numerical beach, similar to physical flumes. For the purpose of this study, Hydro3D-NWT is employed to examine the code’s accuracy by comparing numerical simulations with previously conducted experimental measurements. Results suggest that the present code is capable of predicting the resulting motion of floating structures and the local hydrodynamics involved. Finally, a case of steep regular waves interacting with a floating rectangular box is presented and the results showcase the complex fluid-structure interactions involved in terms of vortex shedding, three-dimensional rotational flow structures and wave elevations.
Year: 2025