대칭단면을 갖는 3 차원 날개의 지면고도에 따른 공력특성과 끝단와 거동

초록

A numerical study has been conducted to investigate the aerodynamic characteristics and behavior of a wingtip vortex around a three-dimensional symmetric wing (NACA0015) in the vicinity of the ground. The aerodynamic characteristics and the wing-tip vortex change as a wing approaches the ground as a result of two different phenomena: the ground effect and the Venturi effect. The ground effect increases lift and decreases drag whereas the Venturi effect generates negative lift and increases drag suddenly. A symmetric airfoil experiences both phenomena with respect to changes in the angle of attack. In the case of a NACA0015 airfoil, the Venturi effect is dominant at small angles of attack but the ground effect is dominant at large angles of attack. Interestingly, both phenomena can be observed at the 4 degree of angle of attack. The vortex core moves inside a wing when the wing experiences the Venturi effect, whereas the vortex core moves outward when the wing experiences the ground effect.

키워드