RU2086467C1 - Aircraft wing - Google Patents

Abstract

FIELD: aeronautical engineering. SUBSTANCE: wing has tip mounted in its plane and provided with shoulder over leading edge; tip has profiles of increased camber as compared with wing and twist angles; end edge of tip before shoulder is sharp smoothly changing into blunt leading edge after shoulder; line of maximum thickness of above-chord section of tip profiles is shifted backward after shoulder over upper contour and is located within 60-80% of local chord of tip. EFFECT: enhanced efficiency. 2 cl, 5 dwg

Description

 The invention relates to aircraft and can be used on airplanes for various purposes.

 It is known that vortices escaping from the wing ends lead to the appearance of inductive resistance and, thus, to a decrease in the aerodynamic quality of the aircraft.

 The formation and intensity of the end vortices is directly affected by the wingtip, the shape and position of which can help reduce the end vortices in certain flight modes.

 Known wings containing endings in the form of end "wings" [1] which through the use of bevels of the flow from the outside of the end vortices reduce the loss of aerodynamic quality of the aircraft.

 However, these devices are complex in shape, have large dimensions and weight, require an increase in the stiffness of the wing, which leads to a heavy structure.

An airplane wing is also known, comprising a tip installed in the wing plane and having a step along the leading edge, in which aerodynamic quality losses are reduced by creating additional suction force in the area of the leading edge of the step, streamlined by the end vortex [2]
However, on the swept wing at high transonic speeds, the efficiency of the device is small, and the aerodynamic quality losses are significant.

 The objective of the invention is to increase the aerodynamic quality of the aircraft, both at subsonic and transonic speeds.

 The solution to the technical problem is achieved by the fact that the wing of the aircraft contains a tip installed in the plane of the wing and having a step along the leading edge. Moreover, the ending is made with profiles with increased curvature and twist angles, the end edge of the ending in front of the ledge is sharp, smoothly turning into the blunt front edge of the ending behind the ledge, is shifted backward along the upper contour and lies in the range (60-80)% of the local chord endings.

 In addition, the sharp end edge of the endings before the ledge in the plan is made with a straight section.

 Figure 1 shows the wingtip in plan; figure 2 the same, in sections of the ending before and after the ledge; figure 3 flow diagram (front view); in FIG. 4 the same (plan view); in Fig. 5 the distribution of the bevels of the flow at the tip.

 The wing of the aircraft contains a tip 1 made on wing 2, the nose 3 of which is provided with a sharp end edge 4 located in front of the ledge 5. The line of maximum thicknesses 6 of the suprachordal section of profiles 7 is at (60-80)%. The first vortex 8 is shown at the wing tip, causing bevels of flow 9 to ledge 5 and 10 after ledge 5, as well as the second vortex 11. The suction of the flow from the end part of the wing and aileron occurs in directions 12 and 13, respectively.

 The device operates as follows. When flowing around the wing, a vortex 8 is formed in its end part, the intensity of which is high due to the presence of a sharp end edge 4 in front of the step 5. This vortex up to ledge 5 causes a favorable upward slope of the flow 10 from its outer side, which creates an additional suction force on the front, rounded edge of the ledge and increases local flow velocities, creating additional rarefaction on the upper surface of the tip behind the ledge 5. The effect of suction of the flow from the end parts of the wing and aileron (12 and 13) reinforces the backward displacement of the line of maximum thicknesses of the suprachordal part of the profiles 6 s (30-50)% to (60-80)% of the end chord. In addition, the rear location of the line of maximum thicknesses of the suprachordal part of the profiles at the tip allows you to "delay in speed" the appearance of supersonic zones and, thus, use the invention at transonic flight speeds.

Research in a wind tunnel was carried out on a model of an airplane with a sweep wing of 25 degrees. elongation of 8.5, narrowing of 3.5 and relative thicknesses of 14-12-11%
Using the invention will improve the aerodynamic quality of the aircraft, which saves aviation fuel.

Claims (2)

 1. The wing of the aircraft, containing the tip installed in the plane of the wing and having a step along the leading edge, characterized in that the tip is made with profiles increased in comparison with the wing curvature and twist angles, while the end edge of the tip before the step is made sharp, smoothly passing into the blunt leading edge of the ending behind the ledge, and the line of maximum thicknesses of the suprachordal part of the ending profiles behind the ledge is shifted back along the upper contour and is located in the range 60–80% of the local chord of the ending.  2. The wing according to claim 1, characterized in that the sharp end edge of the tip before the ledge in the plan is made with a straight section.

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