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Published November 2023 | Published
Journal Article Embargoed

Large-eddy simulations of turbulent flows in arrays of helical- and straight-bladed vertical-axis wind turbines


Effects of helical-shaped blades on the flow characteristics and power production of finite-length wind farms composed of vertical-axis wind turbines (VAWTs) are studied numerically using large-eddy simulation (LES). Two helical-bladed VAWTs (with opposite blade twist angles) are studied against one straight-bladed VAWT in different array configurations with coarse, intermediate, and tight spacings. Statistical analysis of the LES data shows that the helical-bladed VAWTs can improve the mean power production in the fully developed region of the array by about 4.94%–7.33% compared with the corresponding straight-bladed VAWT cases. The helical-bladed VAWTs also cover the azimuth angle more smoothly during the rotation, resulting in about 47.6%–60.1% reduction in the temporal fluctuation of the VAWT power output. Using the helical-bladed VAWTs also reduces the fatigue load on the structure by significantly reducing the spanwise bending moment (relative to the bottom base), which may improve the longevity of the VAWT system to reduce the long-term maintenance cost.

Copyright and License

© 2023 Author(s). Published under an exclusive license by AIP Publishing.


This research was supported by the National Science Foundation Fluid Dynamics Program under Grant No. 1804214 to D.Y. and Grant Nos. 1802476 and 2038071 to J.O.D. N.J.W. acknowledges support from the National Science Foundation Graduate Research Fellowship. M.G. and D.Y. acknowledge the use of the Sabine and Carya clusters from the Research Computing Data Core (RCDC) at the University of Houston. This work was authored, in part, by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding provided by the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Wind Energy Technologies Office. The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes.


Masoumeh Gharaati: Conceptualization (equal); Data curation (lead); Formal analysis (lead); Investigation (lead); Methodology (lead); Visualization (lead); Writing – original draft (equal). Nathaniel J. Wei: Conceptualization (equal); Formal analysis (supporting); Investigation (supporting); Writing – review & editing (equal). John O. Dabiri: Conceptualization (equal); Formal analysis (supporting); Funding acquisition (equal); Investigation (supporting); Writing – review & editing (equal). Luis A. Martinez-Tossas: Investigation (supporting); Methodology (equal); Writing – review & editing (equal). Di Yang: Conceptualization (lead); Funding acquisition (equal); Investigation (equal); Methodology (equal); Project administration (lead); Writing – original draft (equal).

Data Availability

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Conflict of Interest

The authors have no conflicts to disclose.



The files will be made publicly available on November 1, 2024.

Additional details

December 15, 2023
December 15, 2023