Numerical simulation of airfoil Eppler 562 with variations of whitcomb wingtip devices

Wings are one of the aircraft components that play an important role in generating lift. One of the important factors affecting lift on the wing is the aspect ratio of the wing. The theory shows that the use of wings with infinite span length (infinite wing) is the most ideal wing design, but in fact it is impossible to make wings of infinite length. Therefore the wing's length is limited and made with dimensions proportional to the fuselage length of the aircraft. The span length of the aircraft is limited, making a three-dimensional separation on the wing tip section which will form a secondary flow, where this flow gives loss on the performance of the aircraft as it reduces the effective area of the wing and increase the wing drag. One modification on the aircraft wing to reduce the impact of the vortex tip is the use of the winglet on the tip portion of the wing. This has been widely applied to the latest commercial aircraft to improve the efficiency of the aircraft and UAV (Unmanned Aerial Vehicle). The study using numerical simulation was done with simulation software with 3D geometric configuration. The geometry of the model is UAV wing Eppler 562 with chord length of 0.36 m, swept angle 0°and modification of whitcomb winglet with cant angle 90°. The was performed at inlet airflow of 10 m / s and the pressure at the outlet was 0 Pa (gage). The turbulent modeling used is k-ω SST. Discrete method is hybrid mesh with boundary layer mesh method. The results of flow visualization show that withcomb winglet can improve wing performance effectively at high angles of attack, especially at angle α = 8°and α = 10°, which C_L/C_D higher than airfoil without winglet. The rearward wingtip fence effective C_L/C_D is higher than airfoil without winglet after angle α = 10°.