The present paper is aimed at developing a Vertical Axis Marine Current Turbine (VAMCT) by computational studies in order to provide a viable renewable choice in power generation. Computational Fluid Dynamics (CFD) is adopted to investigate the hydrodynamic performance of a straight-bladed Vertical Axis Marine Current Turbine (VAMCT) in term of its power coefficient. In order to effectively optimize the efficiency of a Darrieus-type VAMCT it is necessary to accurately model the hydrodynamic loads on the blades and the flow fields through the turbine. However, CFD simulations of a complete turbine with a refined mesh typically take a number of weeks to perform on a small HPC cluster, due to the very small time steps needed in order to predict the transient unsteady flow field and to capture the turbulent features of the flow through the turbine. Several methods to significantly reduce computation time whilst maintaining a usable level of accuracy are explored. These include using 2D meshes; identifying and reducing the mesh density on uncritical areas; limiting the refined mesh to one blade; simulate as one oscillating blade; combining useful shortcuts. In conclusion, current works demonstrated that the proposed CFD modeling strategy is able to predict the performance of a VAMCT cost-effectively time-wise, whilst also maintaining a usable level of accuracy.
The appreciation and commercialization of the use of renewable energy for electricity generation in the future is eminent. Tidal stream generation while still at its infancy looks promising to offer its share to meet this future demand.