CN112977803B

CN112977803B - Deformed flap with enhanced blowing and sucking in coordination with high lift

Info

Publication number: CN112977803B
Application number: CN202110272005.XA
Authority: CN
Inventors: 肖天航; 支豪林; 朱震浩
Original assignee: Nanjing University of Aeronautics and Astronautics
Current assignee: Nanjing University of Aeronautics and Astronautics
Priority date: 2021-03-12
Filing date: 2021-03-12
Publication date: 2023-02-10
Anticipated expiration: 2041-03-12
Also published as: CN112977803A

Abstract

The invention provides a deformation flap for enhancing blowing and sucking in coordination with high lift, which comprises a wing consisting of a leading edge flap, a wing body and a trailing edge deformation flap, wherein a jet cabin is arranged inside the leading edge flap, and jet holes connected with the jet cabin are arranged on the upper surface of the leading edge flap; a flow suction cabin is arranged in the rear edge deformation flap, and flow suction holes connected with the flow suction cabin are arranged on the upper surface of the rear edge deformation flap; the wing body is embedded with a micro compressor, the micro compressor is respectively connected with the jet cabin and the flow suction cabin through rubber pipes, and the micro compressor sucks and pressurizes airflow from the flow suction holes and then ejects the airflow from the jet holes. The invention combines the blowing-suction cooperative active flow control technology with the deformation flap, is used for a large-scale fixed wing aircraft, generates a high lift enhancement effect, improves the pneumatic characteristics of take-off and landing, realizes short-distance take-off and landing, slows down the pressure of an airport, and simultaneously can also improve the cruising efficiency and increase the voyage.

Description

Deformed flap with enhanced blowing and sucking in coordination with high lift

Technical Field

The invention relates to the field of aerospace aircrafts, in particular to a deformation flap with enhanced blowing and sucking in coordination with high lift.

Background

The wings are main components for generating lift force of the airplane, and the adoption of high lift measures to improve the lift force of the wings is an important technology for improving the taking-off and landing performance of the airplane. Conventional mechanical high lift devices achieve high lift at the expense of increased mechanical complexity and structural weight, and it is currently difficult to further increase lift and improve take-off and landing performance.

The high lift device should be simple and reliable in terms of weight reduction of the structure and reduction of the cost of maintenance in use. The development direction of the wing in the future is a complete and self-adaptive intelligent wing, wherein 'complete' means that the surface of the wing is free of hinges and gaps so as to reduce the resistance and noise of the body structure. Several studies have been carried out in western countries to validate smart wing technology. The intelligent wing adopts an exciter based on the deformation memory alloy to replace a hinge to control the deflection of a flap and a control surface, a conventional leading edge slat can be replaced by a droop type leading edge flap, a trailing edge flap can be replaced by a trailing edge deformation flap, the flap and a main wing are integrated in appearance, and a flexible skin is used for ensuring the smoothness of the wing surface in the deflection process of the flap. The intelligent wing with the deformation flap can greatly improve the flight quality, but the deformation flap has the problem of low maximum lift coefficient, and a new technical approach and a new scheme are urgently required to realize the lifting of the high lift performance.

Active flow control is a technique that increases the energy of the main boundary layer, weakens the separation, and improves the flow quality by certain measures (such as blowing, gettering, or plasma effects). The zero mass flow active flow control technology with blowing and sucking cooperated is concerned with due to the characteristics of lift increase during taking off and landing and drag reduction during cruising. The technology is characterized in that jet holes are arranged near the front edge of a wing, suction holes are arranged near the rear edge of the wing, a micro compressor is installed in the wing to suck and pressurize airflow from the suction holes and then the airflow is sprayed out from the jet holes, the airflow on the upper surface of the wing is accelerated to flow, and the effects of increasing lift, reducing drag and delaying stall are achieved. The existing research on the blowing-sucking cooperative flow control mainly adopts a single-section wing type or an aerofoil, and the preliminary research result shows that the blowing-sucking cooperation can generate an over-circulation effect, so that the lift force and the stall attack angle are obviously improved, but a larger lift force coefficient can be realized only under a larger attack angle, so that the application of the blowing-sucking cooperative flow control on a large airplane is greatly limited, and further research and solution are needed.

Disclosure of Invention

The invention provides a deformable flap with enhanced blowing and sucking in coordination with high lift, which is beneficial to adopting the integrity characteristic that no gap exists on the wing structure of the deformable flap, combines the blowing and sucking in coordination with an active flow control technology with the deformable flap and is used for a large-scale fixed wing aircraft to generate the effect of enhancing the high lift, improve the pneumatic characteristics of taking off and landing, realize short-distance taking off and landing, reduce the pressure of an airport, and simultaneously improve the cruise efficiency and increase the range.

The wing comprises a leading edge flap, a wing body and a trailing edge deformation flap, wherein the leading edge flap and the trailing edge deformation flap are respectively connected with the wing body through a rotating shaft and deflect around the rotating shaft; a flow suction cabin is arranged in the rear edge deformation flap, and flow suction holes connected with the flow suction cabin are arranged on the upper surface of the rear edge deformation flap; the wing body is internally embedded with a micro compressor, the micro compressor is respectively connected with the jet cabin and the flow suction cabin through rubber pipes, and the micro compressor sucks and pressurizes airflow from the flow suction holes and then ejects the airflow from the jet holes.

The method is further improved, the chord length of the wing is taken as a reference, the jet hole is located at the chord length of 2.0% -4.0% away from the front edge of the wing, the height of the jet hole is 0.65% -1.0% of the chord length, the included angle between the jet hole and the vertical direction is 25-30 degrees, and the jet hole is perpendicular to the upper surface of the wing;

the suction hole is located at the chord length of 70.0% -75.0% from the front edge, the height of the suction hole is 1.3% -1.5% of the chord length, the included angle between the suction hole and the vertical direction is 70-75 degrees, and the suction hole is perpendicular to the upper surface of the wing;

the length of the leading edge flap is 15% -17% of the chord length, and the deflection angle range of the leading edge flap is 0-30 degrees; the length of the trailing edge deformation flap is 30% -35% of the chord length, and the deflection angle range of the trailing edge deformation flap is 0-60 degrees.

The outer surfaces of the leading edge flap, the wing body and the trailing edge deformation flap are respectively provided with a deformable flexible skin, so that smooth transition of the wing surface is ensured, and a deformation memory alloy exciter is arranged at a rotating shaft to realize deflection.

The invention has the beneficial effects that:

1. the blowing and suction are cooperated with the active flow control technology, flap airflow is accelerated, flap airflow separation is delayed, and a high-lift enhancing effect is achieved; when the micro compressor works, the trailing edge suction hole sucks airflow and a low-speed boundary layer into an internal airflow pipeline, so that the airflow on the upper surface of the wing is attached to a trailing edge flap, and the flow separation is delayed; the sucked air flow is pressurized by the micro compressor, accelerated to the jet hole and then ejected out perpendicular to the upper surface of the wing, the air flow of the leading edge flap and the upper surface of the wing is accelerated, energy is added to the low-speed boundary layer, the upper surface pressure is reduced, the viscous resistance is reduced, and meanwhile, the resistance can be further reduced through the low-pressure effect of the leading edge flap.

2. The deformation flap is adopted, the flap and the wing are complete, are connected without hinges and have no gap, so that the zero lift resistance of the wing can be reduced, and the noise generated by the wing is reduced;

3. the blowing and suction cooperation and the deformation flap are combined, the problem that a large lift force is obtained under a normal takeoff attack angle is solved, and the lifting force is very suitable for a large fixed wing aircraft, the lifting force in the takeoff and landing process is increased, and the short-distance takeoff and landing is realized.

Drawings

FIG. 1 is a schematic cross-sectional view of a modified flap of the cruise configuration of the present invention;

FIG. 2 is a schematic cross-sectional view of a modified flap of the take-off and landing configuration of the present invention;

FIG. 3 is a modified flap flow field diagram without (left) and with (right) the blow-and-suck synergy technique;

FIG. 4 is a comparative plot of flow fields for different micro-compressor power conditions using a morphing flap with suction and blow synergy;

FIG. 5 is a graph of lift coefficient and lift-to-drag ratio as a function of angle of attack without deflection for a flap deformed using the suction-and-blow synergy technique;

FIG. 6 is a curve of lift coefficient and lift-drag ratio with angle of attack when a droop leading edge flap deflects by 30 degrees and a trailing edge deformation flap deflects by 30 degrees by using a blowing-suction cooperation technique;

FIG. 7 is a graph of lift coefficient and lift-drag ratio as a function of angle of attack for a 30 ° flap deflection and a 60 ° flap deflection of a trailing edge flap deflection using a coordinated technique of blowing and suction.

Detailed Description

The invention will be further explained with reference to the drawings.

The invention discloses a deformed flap with blowing and suction enhanced in coordination with high lift, which comprises a wing composed of a leading edge flap 11, a wing body and a trailing edge deformed flap 12, wherein the leading edge flap 11 and the trailing edge deformed flap 12 are respectively connected with the wing body through a rotating shaft 4 and deflect around the rotating shaft, and a cruise configuration 1 and a take-off and landing configuration 10 are formed according to different deflection angles.

A jet cabin 5 is arranged in the leading edge flap 11, and a jet hole 7 connected with the jet cabin 5 is arranged on the upper surface of the leading edge flap 11; the inner part of the trailing edge deformation flap 12 is provided with a flow suction cabin 6, and the upper surface of the trailing edge deformation flap 12 is provided with a flow suction hole 8 connected with the flow suction cabin 6; the wing body is internally embedded with a micro compressor 2, the micro compressor 2 is respectively connected with a jet cabin 5 and a flow suction cabin 6 through a rubber pipe 3, and the micro compressor 2 sucks and pressurizes air flow 9 from a flow suction hole 8 and then ejects the air flow from a jet hole 7.

Taking the chord length of the wing as a reference, the jet hole 7 is positioned at the chord length position of 2.0 percent away from the front edge of the wing, the height of the jet hole 7 is 0.65 percent of the chord length, the included angle between the jet hole 7 and the vertical direction is 30 degrees, and the jet hole 7 is vertical to the upper surface of the wing; the suction hole 8 is positioned at the chord length of 75.0% of the front edge, the height of the suction hole 8 is 1.3% of the chord length, the included angle between the suction hole 8 and the vertical direction is 75 degrees, and the suction hole 8 is vertical to the upper surface of the wing; the length of the leading edge flap 11 is 15% of the chord length, and the deflection angle range of the leading edge flap 11 is 0-30 degrees; the length of the trailing edge deformation flap 12 is 30% of the chord length, and the deflection angle of the trailing edge deformation flap 12 ranges from 0 degree to 60 degrees.

In the invention, a droop type leading edge flap 11 and a trailing edge deformation flap 12 are adopted, so that the flaps and the main wing form a whole after deflection without gaps, the skin adopts a deformable flexible skin to ensure that the surface of the wing can be in smooth transition, and the deflection of the flaps can be realized by a deformation memory alloy exciter; the jet hole 7 is arranged on the downward hanging type leading edge flap 11, the flow suction hole 8 is arranged on the trailing edge deformation flap 12, and meanwhile, the jet cabin 5 and the flow suction cabin 6 are fixedly connected with the leading edge flap and the trailing edge flap respectively to form a rigid body and deflect together with the flaps; the jet cabin 5 and the tail end of the suction cabin 6 are connected with a micro compressor 10 through a rubber pipe 3 to form an internal airflow pipeline.

The deformation flap with the blowing and sucking synergistic effect and the high lift enhancement provided by the invention can obviously improve the flow field characteristics around the deformation flap, as shown in figure 3, the front flap and the rear flap deflect by 30 degrees, so that the flow at the rear flap can be clearly seen, the deformation flap without the blowing and sucking synergistic technique has completely separated airflow at an attack angle of 6 degrees, the deformation flap combined with the blowing and sucking synergistic effect has airflow completely attached to the rear flap, and meanwhile, the speed of the airflow on the upper surface of the wing is greatly increased due to the blowing and sucking synergistic effect, so that a strong suction peak is generated at the front flap, and the effects of increasing lift and reducing drag are achieved. As the flow velocity on the upper surface of the wing is increased, the pressure is further reduced, and then high lift force is generated. The trailing edge is eliminated due to the blowing and sucking synergistic effectThe stall characteristic is greatly improved. With the further increase of the power of the miniature compressor, the gain effect of the blowing and sucking synergy on the deformation flap is more obvious. Using a dimensionless momentum coefficientC _μ Representing the compressor power. As shown in FIG. 4, when the trailing edge flap is deflected by 60 degrees, increasing the power of the compressor can significantly reduce the flow separation on the trailing edge flap, and at the same time, the stagnation point position can be moved backwards along the lower surface of the wing, thereby increasing the circumferential flow of the wing, accelerating the airflow on the upper surface of the wing and further increasing the lift force.

FIGS. 5-7 are variation curves of lift coefficient and lift-drag ratio with an attack angle of a blowing-suction synergistic high-lift enhanced deformation flap obtained through CFD simulation under different flap deflection angles and different compressor powers. It can be seen that, as the power of the compressor is increased, the lift force is further increased, and the lift-drag ratio is also superior to that of the lift-drag ratio without adopting the blowing-suction synergistic technology. As the flap deflection angle increases, the maximum lift coefficient increases, while a larger compressor power needs to be guaranteed to prevent stall. It can be seen from fig. 6 that, at a normal take-off and landing angle of attack, when the leading edge flap deflects by 30 ° and the trailing edge flap deflects by 60 °, the lift coefficient of the flap can be increased to 5.0 or more by the blowing-suction synergistic effect.

While the invention has been described in terms of its preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

Claims

1. The utility model provides a deformation flap that blowing and suction synergized high lift enhancement, includes the wing of constituteing by leading edge flap (11), wing body and trailing edge deformation flap (12), and leading edge flap (11) and trailing edge deformation flap (12) are connected and deflect around the pivot through pivot (4) and wing body respectively, its characterized in that: a jet cabin (5) is arranged in the leading edge flap (11), and jet holes (7) connected with the jet cabin (5) are arranged on the upper surface of the leading edge flap (11); a flow suction cabin (6) is arranged in the trailing edge deformation flap (12), and a flow suction hole (8) connected with the flow suction cabin (6) is arranged on the upper surface of the trailing edge deformation flap (12); the wing body is internally embedded with a micro compressor (2), the micro compressor (2) is respectively connected with the jet cabin (5) and the flow suction cabin (6) through a rubber pipe (3), and the micro compressor (2) sucks and pressurizes air flow (9) from a flow suction hole (8) and then ejects the air flow from a jet hole (7); taking the chord length of the wing as a reference, the length of the leading edge flap (11) is 15-17% of the chord length, and the deflection angle range of the leading edge flap (11) is 0-30 degrees; the length of the trailing edge deformation flap (12) is 30% -35% of the chord length, and the deflection angle range of the trailing edge deformation flap (12) is 0-60 degrees; taking the chord length of the wing as a reference, the jet hole (7) is located at the chord length of 2.0% -4.0% away from the front edge of the wing, the height of the jet hole (7) is 0.65% -1.0% of the chord length, the included angle between the jet hole (7) and the vertical direction is 25-30 degrees, and the jet hole (7) is perpendicular to the upper surface of the wing; the chord length of the wing is taken as a reference, the suction hole (8) is located 70.0% -75.0% of the chord length away from the front edge, the height of the suction hole (8) is 1.3% -1.5% of the chord length, an included angle between the suction hole (8) and the vertical direction is 70% -75 degrees, and the suction hole (8) is perpendicular to the upper surface of the wing.

2. The blow and suction cooperative high lift enhanced morphing flap of claim 1, wherein: the outer surfaces of the leading edge flap (11), the wing body and the trailing edge deformation flap (12) adopt deformable flexible skins, and a deformation memory alloy exciter is installed at a rotating shaft.