Numerical Study of the Effect of the Co-Flow Jet on the Aerodynamic Coefficients of a Kilowatt Horizontal Axis Wind Turbine Blade

Document Type : Research Note

Authors

Faculty of Mechanical Engineering, Tarbiat Modares University

Abstract

In this study, numerical investigation is conducted on using Co-flow jets in the wind turbine blades. 3D steady simulations are performed using k-kl-ω turbulence model. Different jet flow coefficients ranging from 0.00 to 0.03 are applied at wind speeds of 7, 10, 15, and 20 m/s to evaluate the influence of suction and blowing slots located near the trailing edge of the blade. The results indicate that CFJ has negligible impact at very low wind speeds (7 m/s), but it provides substantial performance improvements at moderate to high wind speeds. At 10 m/s, CFJ coefficients of 0.02 and 0.03 enhance the net power coefficient significantly. At 15 m/s, the use of CFJ with Cμ = 0.01 results in a 33% increase in turbine performance and successfully delays the onset of dynamic stall. At 20 m/s, a further improvement of 8% is observed with Cμ = 0.03. Overall, the study demonstrates that CFJ is a highly effective technique for improving aerodynamic efficiency and power generation in kilowatt-scale wind turbines, particularly in regions with medium to strong wind conditions.

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