Univariate analysis of scaling effects on the hydrodynamics of tidal current turbines

Tidal energy, a promising marine renewable resource, has gained significant attention due to its predictability, stability, and low environmental impact. However, tidal current turbines are often limited by local hydrodynamic conditions such as flow velocity and water depth. The performance of these turbines depends on factors like Reynolds number and tip speed ratio (TSR), which impact power output, blade loading, and system stability. This study uses high-resolution numerical simulations and non-dimensional analysis to investigate the influence of Reynolds number and TSR on turbine performance across various scales. The analysis considers both blade load distribution and near-wake characteristics, highlighting how tip vortices, effective angle of attack, and flow separation affect the hydrodynamic performance of tidal current turbines. At low Reynolds numbers (e.g., small-scale turbines), performance degradation is more pronounced due to enhanced tip vortex effects. By systematically mapping non-dimensional results to different geometric scales and operating conditions, this study provides a robust framework for predicting turbine performance at multiple scales. These insights not only inform blade design and rotor optimization but also guide the engineering of tidal energy systems to achieve improved power generation, reduced structural loads, and enhanced overall reliability.