Improvement of the take-off and landing characteristics of wing using an ejector pump

Abstract

The effectiveness of use of an ejector pump for controlling the flow around a wing under take-off and landing conditions of flight is investigated. The proposed device permits organization of simultaneous suction of boundary layer through a slot on the upper surface of the wing and gas blowing in the vicinity of the trailing edge of wing through a flat slot-type diffuser; the latter makes it possible to effectively implement the principle of wing-flow control using gas suction and jet blowing. The design of the ejector pump makes it possible to obtain values of suction and blowing velocities of order 50–100 m/s. The paper proposes a mathematical model of the flow around the wing airfoil taking into account the operation of the ejector pump, and presents results of a computational study of aerodynamic characteristics of one- and three-element wing airfoil under landing conditions. It is shown that the simultaneous use of suction and blowing improves the flight characteristics of the mechanized airfoil more effectively in comparison with the separate use of these means.