Comparison of flow structures for vane and rod type vortex generators on a wind turbine airfoil
International Journal of Numerical Methods for Heat & Fluid Flow
ISSN: 0961-5539
Article publication date: 20 January 2023
Issue publication date: 24 April 2023
Abstract
Purpose
The purpose of this paper is to investigate and compare the effects of rod and vane-type vortex generators for wind turbine applications. In large wind turbine rotors, an attached flow at all sections along the span direction is difficult to achieve which leads to an increase in aerodynamic losses, noise generation, and fatigue stress. Therefore, flow control strategies such as vortex generators (VGs) are beneficial to improve performance.
Design/methodology/approach
The benefits of the application of rod-type vortex generators (RVGs) to control flow separation on a wind turbine airfoil are assessed numerically using computational fluid dynamics (CFD). The validation of the computational model is conducted against the experimental data available for the DU96-W-180 wind turbine airfoil equipped with 44 RVGs. In addition, a revised wind tunnel angle of attack (AoA) calibration procedure (based on CFD) is proposed that is applicable for separated flows. A comparison of the RVGs to the conventional vane-type vortex generators (VVGs) is presented for inflow velocity of 30 m/s and AoA leading to significant flow separation. A parametric evaluation of the geometric characteristics of both types of VGs is conducted to quantify the generated streamwise vortices.
Findings
The comparison of the induced flow structures and aerodynamic efficiency enhancements proves that RVGs may be used as an alternative to the more conventional VVGs applied on wind turbine blades for boundary layer separation control.
Originality/value
A new type of VG (rod) has been investigated and compared against conventional VG (vanes) for wind turbine applications.
Keywords
Acknowledgements
The project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Grant Agreement No. 860101 – zEPHYR and has been supported by CI TASK (Gdansk, Poland). Experimental data are taken from the SmartAnswer project (Grant No. 722401). The authors would like to express their gratitude to Daniele Ragni and his team from TU Delft for their valuable support during the measurements.
Citation
Tiwari, N., Flaszynski, P., Suresh, T. and Szulc, O. (2023), "Comparison of flow structures for vane and rod type vortex generators on a wind turbine airfoil", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 33 No. 4, pp. 1458-1474. https://doi.org/10.1108/HFF-09-2022-0564
Publisher
:Emerald Publishing Limited
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