Aerodynamic Performance Enhancement of NACA4418 Airfoil Involving Gurney Flap-passive Flow Jet Control:A Computational Fluid Dynamic Analysis

The objective of the present study is to enhance the aerodynamic performance of the NACA 4418 airfoil equipped with a Gurney flap. To achieve this improvement, a novel technique employs the new pressure distribution caused by the Gurney flap to generate a passive jet. The passive jet is created by ducting the flow from the high-pressure region on the lower surface upstream the Gurney flap to the low-pressure area on the upper surface, where flow separation occurs. To evaluate the effectiveness of the proposed technique, high-fidelity Computational Fluid Dynamics analyses are conducted, at a Reynolds number of 3.8×105, using Ansys Fluent software. The passive jet-blowing location and the angle of attack are considered key parameters in this study. The findings show an increase in lift, particularly at pre-stall angles, with a 0.7 improvement in the maximum lift coefficient compared to the baseline case, a reduction in drag, and a 4° increase in the stall angle compared to Gurney Flap Only.