A research on studying the effect of the wake generated by an aircraft wing section on a following aircraft wing section is performed. NACA 2412 is chosen as the airfoil model in this project. The airfoil model is fabricated by using CNC machining. Aluminium is chosen as the material for the airfoil model because it provides a good surface finish. Three experiments are conducted by using the open-circuit wind tunnel in Universiti Sains Malaysia (USM). The wind tunnel tests were carried out at the velocity of 5m/s to 30m/s in a test section of the size 0.30m (W), 0.30m (H) and 0.60m (L), at the Reynolds number of 4.10 x 104 to 2.54 x 105. Experiment 1 is the testing of single airfoil model to define the coefficient of lift, coefficient of drag and Reynolds number at various angles of attack. Experiment 1 is functioning as references for comparison for Experiment 2 and Experiment 3. Experiment 2 and Experiment 3 are the testing of two airfoil models at a separating distance of 1 chord length (13cm) and 2 Chord lengths (26cm) respectively. The main objective of Experiment 2 and Experiment 3 are to study the effects of wake turbulence on the characteristic of coefficient of lift, coefficient of drag and Reynolds number of a following airfoil model when an airfoil model is placed in front of it at a specific distance. The characteristics of the wake generated by an airfoil model on a following airfoil model are observed and studied during the testing in wind tunnel. Further investigations, discussions and conclusions are carried out throughout completing this research project. The results show that the separating distance between the two airfoils affects the coefficient of lift, coefficient of drag and the stall angle of the following airfoil at various angle of attack and free stream velocity
