Faez A. The method of extrtaction of nonlinear aerody-namics airfoil with jet flap

The jet flap is formed by a jet that flows out of the thin slot at the wing trailing edge at high speed. It changes the wing lift both directly through reaction at the internal wall of the air passage and by redistribution of pressure on upper surface of the wing, i.e. as a consequence of supercirculation. As supercirculation can increase the lifting power, and the jet reaction trans-forms mainly to the propulsive force, the jet flap is a combined facility for creating the lifting and propulsive forces of the jet aircraft. The first theoretical studies of a two-dimensional airfoil with a jet flap close to land were based on prime lifting-line theory. Then generalization of the problem of land influence was made (using the method of conformed transformations).High-speed transport aerodynamic crafts will evidently operate in such conditions when ratio between distance to land and root wing cord will be less than 0.1. This research shows solu-tion of the non-linear problem of land influence for the two-dimensional wing. Solution is found by methods of the theories of potential and binding the viscous flow in the jet with external po-tential flow. An important feature of this method is that with its help this problem is solved as a direct problem of flow resulting from known distribution of peculiarities along the upper surface of the wing and jet sheet. Thus, even for the random-form wing it's possible to avoid difficulties connected with inverse transformation of the integral equation. It is clear that in the area close to the trailing edge special transformations are required, as the Kutta-Joukowski's condition for the trailing edge is inapplicable to wings with the jet flap. Instead, there is a condition that the jet flows out of the trailing edge at the deviation angle. The research gives results of theoretical studies of the author in aerodynamics of flat bod-ies with jets obtained on the basis of formulated general setting the problem of jet flow over bod-ies. The studies presumed that flows are steady, free-vortex; the fluid is ideal and weightless. Non-linear theory of smooth flows, enabling in incompressible fluid to efficiently solve various problems in case of no tangential discontinuity of speed, is developed. There is given the theory and iteration method leading to precise solution of problems of three determinations of aerodynamic characteristics and form of jet in the cross-flow.