Operational fatigue loading on tidal turbine blades using computational fluid dynamics

As the world moves to a greater reliance on renewable energy, a vital component will be the predictability and dependability of the energy source; tidal energy provides such a solution. Horizontal axis tidal turbines are the most mature technology of all the marine renewable energy devices currently under development, as full-scale porotypes are already being tested and operated. As the industry develops and strives for commercial viability, it is becoming increasingly vital to develop a robust understanding of the complex interaction between the tidal flow, turbine blades and the support structure. This study uses an advanced computational fluid dynamics model to explore the operational fatigue loadings induced on tidal turbine blades. Two factors are considered, the presence of a support structure and varying vertical velocity profile of the tidal current. In order to perform the investigation, a model of a concept 16 m diameter horizontal axis tidal turbine with a monopile support structure is created. An investigation of the operational fatigue loadings due to variations in the positioning and the diameter of the support structure, the tidal turbine blade loads were found to varying by up to 43% of the maximum total thrust force.This research was funded in part by Science Foundation Ireland (SFI) through the Marine and Renewable Energy Ireland (MaREI) research centre (Grant no. 12/RC/2302), Science Foundation Ireland (SFI) under Grant Number 16/IFB/4512, the Sustainable Energy Authority of Ireland (SEAI) through the Ocean ERA‐NET Ocean Energy Prototype Research and Development Programme 2018 as part of the SEABLADE project (Award no.: 18/OCN/102) and the European Commission under the FloTEC project (Floating Tidal Energy Conversion, Funded under: Horizon 2020, Low Carbon Energy (LCE), Grant Number: 691916). The last author would also like to acknowledge the support of Science Foundation Ireland through the Career Development Award programme (Grant No. 13/CDA/2200). The authors would like to express their gratitude to the Irish centre for high‐end computing (ICHEC) for the computation processing power provided. The authors would like to acknowledge Dr Philippe Gleizon and the Environmental Research Institute at the Centre for Energy and the Environment of the University of the Highlands and Islands, UK for their kind contribution of the ADCP data for the Inner Sound, Pentland Firth.peer-reviewed2022-01-2