Selecting the mutual arrangement of the engine and wing in a transport aircraft for short take-off and landing

Abstract

In order to maintain the competitive advantage of the medium short takeoff and landing transport aircraft, the task must be solved of ensuring takeoff and landing on the ground runways with a length of 600-800 m when installing a turbojet engine. When the engines are installed on the pylons under the wing, this is achieved by using a «forced» turn of the jet of engines when the flaps are released at an angle of 60°. We have found the mutual location of the wing and the engine on its stagger, based on the position relative to the construction plane of the wing and the angle of installation. A reciprocal arrangement has been determined, making it possible to maximize the lift force owing to the turn of the jet stream. It has been shown that this achieves the continuous flow around the sections of the flaps when they are deflected at a 60-degree angle. We have analyzed the temperature effect of the jet stream on the mechanization and the aircraft wing at the stages of takeoff and landing at different positions of engines under the wing, at different flight speeds and angles of attack. The effect of mechanization on the distribution of jet stream speeds and temperatures has been analyzed. It is shown that decreasing the distance between the engine nozzle and the lower surface of the wing leads to an increase in the angle of the jet stream deviation. We have identified those tail section zones of the flap, which require special execution to operate at temperatures above 400 °C. The impact of the jet stream on aircraft's drag in the cruising configuration has been analyzed, as well as the scheme of engine arrangement on the aircraft's electrically dependent systems. We have shown the absence of the impact of the jet stream on the aircraft's drag in the cruising configuration, the reduction of fuel consumption at cruising modes, as well as the favorable impact exerted on the electrically dependent systems due to the significant reduction of gas-dynamic losses along the power plant tract. Ways to modernize the transport aircraft type of An-70 have been proposed to ensure its superiority in its class