Parametric Evaluation of Cross-Flow Turbine Performance

The present paper discusses an experimental investigation of the key parameters influencing cross-flow turbine efficiency. The experiments included measurements of torque, rotational speed, flow rate, and total head in physical models of turbines and nozzles. One physical parameter (flow rate) and six geometric parameters of the turbine were investigated: the angle of water entry to the runner, diameter ratio, number of blades, flow-stream spreading, runner aspect ratio, and blade exit angle. A total of 39 runners and 11 nozzles were tested in 75 different combinations. Analysis performed on the results identified the impact of the different parameters on the turbine efficiency. The results indicate that with careful selection of the cross-flow turbine parameters, efficiencies as high as 88.0% with an uncertainty of [+-]2.4% can be achieved. This is considered an improvement over the claimed maximum efficiency reported in the literature.