Numerical characterization of a preliminary portable micro-hydrokinetic turbine rotor design

Portable micro-hydrokinetic turbines are designed and characterized using computational fluid dynamics (CFD) simulations. The two equation k-ω shear-stress transport (SST) turbulence model is employed to predict quasi steady flow structures for a wide range of tip-speed ratios. Seven input design parameters selected a priori are used to create preliminary turbine rotor designs by using a hydraulic design methodology. Various blade designs are characterized and compared in terms of torque and thrust over a range of operating conditions. Performance characteristics of two, three, and four blade designs are shown to be similar. The results indicate that a maximum power coefficient of 0.43 with a 73.7% efficiency relative to Betz limit is achieved. The portable hydrokinetic turbines, designed and characterized here, do not require large civil structures, making this technology an attractive alternative to conventional hydropower.