Wind power of small wind turbines in turbulent open jets

Abstract Open jet wind tunnel testing provides an alternative solution to expensive online wind power measurements for researchers and small wind turbine developers. However, there is a lack of knowledge for high Reynolds number and large diameter jet flows. In this paper, the structure of circular open jet flows is reviewed. Theories and experimental correlations are combined to extend our understanding of fully developed turbulent jets. Analytical relations are derived to calculate the correct wind power of the jets. The corresponding reduction in power generated by small wind turbines is explained. The effects of various parameters on the power production of a small wind turbine, such as the jet diameter, the distance of the wind turbine from the jet nozzle and the wind turbine hub diameter, are investigated and the results are discussed.

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