Articles | Volume 6, issue 6
Wind Energ. Sci., 6, 1413–1425, 2021
Wind Energ. Sci., 6, 1413–1425, 2021

Research article 09 Nov 2021

Research article | 09 Nov 2021

Some effects of flow expansion on the aerodynamics of horizontal-axis wind turbines

David H. Wood and Eric J. Limacher

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Cited articles

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Branlard, E. and Meyer Forsting, A. R.: Assessing the blockage effect of wind turbines and wind farms using an analytical vortex model, Wind Energy, 23, 2068–2086, 2020. a
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Short summary
The airflow through a wind turbine must expand as it goes through the blades for them to extract energy from the wind. Expansion has not been properly incorporated in wind turbine aerodynamics. We show that the conventional equation for wind turbine thrust becomes inaccurate when the expansion is maximized to achieve maximum power, and expansion reduces power by around 6 %. We formulate equations for the disturbance of the external flow and show that this is maximized at the rotor plane.