Modelling the Impact of Structure Generated Shadowing on Tidal Stream Turbine PerformanceΒΆ
This conference paper investigates the effects of turbine foundation shadowing on performance, using CFD to assess cyclic loading and its implications for design.
Abstract
Many tidal stream turbine developers are now opting for fixed yaw devices, in favour of design simplicity and reliability. For every other flood and ebb cycle, these turbines will operate downstream of their floating or fixed foundation, inducing cyclic loading fluctuations impacting power performance and fatigue life. This study investigates the severity and implications of the foundation shadow effect by applying Computational Fluid Dynamics (CFD) modelling techniques to simulate turbine performance in a downstream operating condition. Results show that shadowing can reduce power output by 5-10% and increase fatigue loads significantly. The study proposes mitigation strategies, such as foundation design modifications, to minimize these effects. The findings are crucial for improving turbine reliability and optimizing array performance in tidal environments.