Analysis on the aerodynamic performance of vertical axis wind turbine subjected to the change of wind velocity

Reynolds averaged Navier-Stokes equations and Realizable kɛ− model were used in this paper, and the two dimensional unsteady flow field of the vertical axis wind turbine was simulated numerically at different wind velocity. The calculation results showed that the velocity in the region of wind turbine's rotation was much larger than the air flow of the upstream. The length of the wind turbine's downstream wake dispersion region was increased with the increase of the wind velocity. There is a much larger value of the eddy in the rear region of the wind turbine's rotational blades. And eddy existed in the downstream region of the wind turbine, and the larger velocity of cross flow, the larger value of the downstream flow's eddy. When the rotational speed was constant, with the increase in wind velocity, the variation of the wind turbine's total torque coefficient tended to smooth. The calculation results pointed out the direction for the follow-up study.