Session: 09-07-02 Tidal & Current Energy I

Submission Number: 180703

Fully-Coupled Numerical Simulation of a Floating Tidal Stream Turbine Under Wave-Current Interactions 

Floating tidal stream turbines are increasingly recognized as a promising approach for harnessing renewable and environmentally friendly energy from marine resources. A reliable model is in need for design and safety evaluation of a tidal stream turbine under ocean conditions. To this end, an integrated computational fluid dynamics (CFD) model is developed within the framework of OpenFOAM-v2406 to simulate the behavior of a floating tidal stream turbine operating under combined wave-current conditions. The model comprises four key modules: hydrodynamics, mooring systems, floating platform motion, and tidal stream turbine dynamics. Hydrodynamic interactions and mooring line behavior are modeled using the open-source tools waves2Foam and MoorDyn, respectively. The dynamic actuator line method is adapted to represent the floating turbine rotor accurately. Notably, the model incorporates the influence of turbine-generated forces on platform motion through a newly implemented six-degree-of-freedom (6DoF) motion library. To verify the accuracy of the integrated model, each component is individually validated against experimental data available in the literature. The validation results show good agreement with previously published findings, confirming the model's reliability and predictive capability. Case studies are presented to demonstrate the functionality of the integrated model. The results indicate that, under wave-current loading, the floating platform undergoes re-positioning as well as periodic heave and surge motions. The turbine rotor induces additional downstream displacement of the platform and amplifies its dynamic response. These intensified motions also result in increased tension in the mooring lines. Furthermore, the turbine rotor experiences performance fluctuations due to its interaction with the platform’s motion. In addition, impacts from wave period and wave height on the response of the floating tidal turbine system are also quantitively investigated. Overall, the developed CFD model provides a comprehensive and reliable tool for the design, analysis, and safety assessment of floating tidal stream turbine systems in real-world marine environments.

Presenting Author: Xiangfeng Lin National University of Singapore

Presenting Author Biography: I am currently a Research Fellow at the National University of Singapore (NUS), specializing in tidal current energy. My research primarily involves the application of ​​Computational Fluid Dynamics (CFD)​​ to advance the understanding and development of tidal energy technologies. At the moment, my work focuses on high-fidelity simulation of tidal stream turbines, including detailed analysis of turbine-fluid interactions, wake dynamics, and performance optimization under complex marine conditions.

Authors:

Xiangfeng Lin National University of Singapore
Yuzhu Pearl Li National University of Singapore