Analysing the Aerodynamic Performance of a Gurney Flap on a Multi-Element Aerofoil

This study focuses on the importance of high-lift systems and devices in enhancing aircraft performance and competitiveness in aircraft development and design. The study conducts a literature review on Gurney Flaps and their implementation on multi-element wings or aerofoils. The CFD simulations are utilized to analyse the aerodynamic characteristics of a multi-element aerofoil system, using NHLP as the selected aerofoil for all three components. The numerical simulation is divided into two stages: developing an accurate CFD setup and validating the results with available experimental data, which show good agreement with the mesh setting. Finally, three different sizes of Gurney Flaps (1%C, 1.5%C &%C) are added to the trailing edge of the aerofoil for further analysis. According to the results, the Gurney flaps dramatically increased lift coefficients at different sizes where 2%C Gurney Flap height was the best size by increasing to 4.1 compared with 3.98 for clean aerofoil. Correspondingly, increasing the height of the GF led to higher drag coefficients when compared with a clean aerofoil. Furthermore, the results showed that the aerodynamic velocity and the pressure continued to increase on the upper surfaces of the slap and main components of the aerofoil till 10°; hence, it led to increased lift system performance. Overall, the results of this work proved that the Gurney Flap significantly affects the lift system performance of the multi-element aerofoil. It could also be a great solution to minimise operating costs, fuel savings and environmental emission reduction, especially during cruise flights.