CFD numerical simulation of wave interaction for a TLP floating offshore wind turbine with porous structural members

Abstract

Designing stable floating support structures for offshore wind turbines in energetic environments is crucial to reducing the cost of energy. Porous structural members are commonly employed in offshore structures to passively attenuate wave reflection. Using a Computational Fluid Dynamics (CFD) numerical model, this paper investigates the motion response of a Tension Leg Platform (TLP) with porous outer structural members. It is further extended to study the hydrodynamic loads and flow fields with various wave conditions, Numerical validation was performed with data from physical model tests conducted at Dalian University of Technology. The results demonstrate that incorporating porous outer structural members significantly reduces the surge response and mooring line tension of the TLP platform. Notably, the fundamental frequency of the surge motion undergoes a significant shift. The mechanism behind this phenomena is analyzed through wave-structure interaction modeling, revealing that the opposite velocity phase of water particles on either side of the porous members leads to a decrease in horizontal hydrodynamic loads. Additionally, the porous elements increase the viscous damping ratio of platform motions, achieving a 43.1 % reduction in peak tendon tension. These findings highlight the potential benefits using porous structural components to enhance the performance and economic viability of floating offshore wind turbine (OWT) systems.