Numerical investigation of modal and fatigue performance of a horizontal axis tidal current turbine using fluid-structure interaction

Abstract The tidal power has the potential to play a vital role in a sustainable energy future. The main objective of this paper is to investigate the performance and fatigue life of tidal current turbine (TCT) using fluid structure interaction (FSI) modelling. The performance of TCT was predicted using Ansys CFX. The performance curve, pressure distribution on the blade, and velocity streamline were visualized for eight repetitive analyses at different tip speed ratio. The hydrodynamic load calculated from CFD analysis was transferred to FEA model for investigation of the structural response of TCT. Modal analysis was performed to examine the mode shapes and natural frequencies of TCT. The fatigue analysis were performed and number of cycles and safety factor at different equivalent alternating stresses were investigated. The results of the simulation confirm that the turbine has a maximum value of the coefficient of performance at λ = 5, the turbine operating frequency is not close to its natural frequency, and it is safe under the applied fatigue loads with a high factor of safety.