Maximizing the Peak Lift-To-Drag Coefficient Ratio of Airfoils by Optimizing the Ratio of Thickness to The Camber of Airfoils

Document Type : Original Research Article


1 Department of Mechanical & Marine Engineering, Chabahar Maritime University, Chabahar, Iran

2 Faculty of Engineering and Technology, Islamic Azad University, Germi, Iran

3 Laboratory of Applied Research in Active Controls, Avionics, and AeroServoElasticity LARCASE, ÉTS-École de Technologie Supérieure, Université de Québec, Montréal, QC H3C 1K3, Canada

4 School of Engineering, RMIT University, Melbourne, VIC-3000, Australia


The paper investigates the lift-to-drag coefficient ratio (CL/CD) efficiency of three airfoils, namely E387, RG15, and SD6060. The objective is to optimize the airfoils for maximum CL/CD efficiency and evaluate them using XFOIL software. The study focuses on these airfoils' performance at different Reynolds numbers (Re) from 500,000 to 1,000,000, with varying thickness-to-camber ratio percentages (t/c%). The results indicate that the E387-Opt airfoil improved the maximum CL/CD by 18.92% at Re 500,000, 23.77% at Re 600,000, 27.14% at Re 700,000, 32.44% at Re 800,000, 32.93% at Re 900,000, and 38.46% at Re 1,000,000. The RG15-Opt airfoil also demonstrated impressive performance, with a maximum CL/CD increase of 34.38% at Re 500,000, 36.75% at Re 600,000, 38.54% at Re 700,000, 41.58% at Re 800,000, 45.57% at Re 900,000, and 51.30% at Re 1,000,000. Finally, the SD6060-Opt airfoil showed even better results, with a maximum CL/CD increase of 37.07% at Re 500,000, 38.16% at Re 600,000, 42.44% at Re 700,000, 48.99% at Re 800,000, 53.10% at Re 900,000, and 56.91% at Re 1,000,000.


Main Subjects

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