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Power production of the counter-rotating tidal current turbine, including duct effect

ABSTRACT In this paper, a counter-rotating tidal current turbine (CRTCT) with and without duct is investigated by Reynolds-Averaged Navier-Stokes (RANS) equation method. The (Shear Stress Transport) turbulence model is adopted in the steady-state simulation. To validate the accuracy of the numerical simulation, a single horizontal axis tidal stream turbine (HATST) is analysed and the numerical results of the thrust and power coefficients are compared with the experimental data at various tip speed ratios (TSR). It was found that numerical results agree well with the experimental data. The simulation method is extended to the CRTCT with and without duct. It is indicated that the total power coefficient of ducted CRTCT is 33% bigger than that of without duct. Moreover, different numerical results of the power, torque, and thrust coefficients of the rear and front turbines, pressure and velocity contours, and streamlines are presented and discussed.