Aerodynamic Quality of Thin Wing with Winglets of Various Heights

The paper considers the problem of asymmetrical airflow around a thin wing with winglets. There is studied the effect of winglets height on lifting force and aerodynamic quality of a thin wing. In frames of this theory, the problem is reduced to a system of three dual integral equations. To solve this system, a discrete form of equations which based on the discrete vortex method is presented. A method for calculating inductive drag, viscous friction, suction force and aerodynamic quality is described. There are presented the data obtained by using a mathematical model, which is based on a linearized theory of thin wing and a method of small perturbations. Conclusions about the effect of winglets on the lifting force and aerodynamic quality are made. Increasing the height of the winglets leads to a linear increase in lifting force. It is noted that at angles of attack up to 4°, winglets do not increase aerodynamic quality. At angles above 4°, increasing the height of the winglets increases aerodynamic quality of a thin wing.