Modelling Approaches for Flow over a Wind Turbine Blade

Abstract

This work models the aerodynamic performance of a wind turbine blade using computational fluid dynamics and strip theory. The wind turbine blade design was supplied by Twin Turbines Ltd. It is a constant tip-speed ratio design, using stall regulation for power control in winds above the rated speed. The analysis uses the commercial computational fluid dynamics program CFX-5. The software model of the wind turbine blade includes rotation simulated using a rotating domain. The results from this model are compared to the solutions obtained using the strip theory method for wind turbine performance analysis. Finally, the stall regulation of the blade at high wind speeds is investigated, using both CFX and the strip theory model. The results from the two methods show good agreement with each other, and indicate that the regulation effect is likely to be smaller than had been expected by the intended manufacturer, Twin Turbines Ltd.

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