Image Theses and Dissertations The Effects of Blockage Ratio and Distance from a Free Surface on the Performance of a Hydrokinetic Turbine Blockage ratio and distance below a free surface are two factors that potentially affect hydrokinetic turbine performance. The extent of the effects of these parameters is considered by determining the coefficient of performance of a simple turbine blade rotating at 250 RPM in a 3.5-m/s flow of water using FLUENT Computational Fluid Dynamics software. View Item