Effect of Flap Deflection on Single-Element Wing Flow Characteristics in Wing Airfoil NACA 43018

Single-element wing means adding certain components to improve the aerodynamic performance of the wing. The enhance components can be in the form of high lift devices or control surfaces. Flap is one of the components commonly used in light aircraft and commercial aircraft today. The deflection exhibited by the flaps on the wings during flight will have an effect on the performance of the aircraft. This study uses a wing with airfoil NACA 43018 using flap deflection δf = 0^o, 15^o and 30^o compared to the performance of plain wing. The angle of attack used is α = 0^o, 2^o, 4^o, 6^o, 8^o, 10^o,12^o,15^o,17^o,19^o and 20^o. This numerical simulation uses a turbulent model k-ε realizable with Re = 3.76 x10⁵. The use of flap deflection variations gives an increase in the value of the drag coefficient and also the lift coefficient. In the use of angle of attack α = 6^o, flap deflection δf = 0^o showed the best aerodynamic performance but after that flap deflection δf = 15^o showed better improvement. The effect of the gap size of the flap cannot be ignored because it affects the flow pattern around the wingtip and the area towards the midspan.