CN107804469B - Aircraft - Google Patents

Abstract

The invention discloses an aircraft. The aircraft comprises a cylindrical fuselage, a full-motion front wing arranged on the front section of the fuselage, an engine arranged above the tail section of the fuselage, and a wing arranged on the middle and rear sections of the fuselage, wherein the wing adopts an upper single wing with a supporting rod, and one end of the supporting rod is connected to the abdomen of the fuselage, and the other end of the supporting rod is connected to the upper single wing. The aircraft provided by the invention has the characteristics of low resistance and low noise, can obviously improve the fuel economy of the aircraft, obviously reduce the noise in the cabin, and has excellent maneuverability and stability.

Description

Aircraft

Technical Field

The present invention relates to aerodynamic arrangements for aircraft, and in particular to aircraft employing novel aerodynamic arrangements.

Background

The aerodynamic layout of an active civil aircraft is called a conventional aerodynamic layout. The main characteristic is that the lower single wing, the wing hanging and the large duct are compared with the turbofan engine (few of the engines still adopt tail hanging engine layout), and the vertical tail fin and the horizontal tail fin are in an inverted T shape or a T shape. Through decades of evolution, the performance and economy of such conventional pneumatically laid civilian aircraft have evolved to a bottleneck period, which is difficult to promote. Therefore, the unconventional pneumatic layout civil aircraft becomes an important direction for seeking comprehensive performance breakthrough of the aircraft. There have been some attempts by aviation enterprises in various countries to develop unusual aerodynamic layouts.

For example, NASA and subsonic green airplane project by boeing company, proposed SUGAR volt transonic truss support wing layout civil airplane. However, the scheme still has obvious defects in maintaining the laminar flow area of the wing, the safety of the blasting of the engine rotor, the control of noise in the cabin and the like.

For another example, the italian P180 aircraft from beljoe employs a tri-winged layout, as does the boeing CN1525920a patent, but both suffer from significant drawbacks in terms of fuel economy and safety associated with engine rotor blasting.

Therefore, there is a need for an innovative aerodynamic layout of an aircraft that is expected to significantly improve the fuel economy of the aircraft while providing low noise characteristics, while compromising the maneuverability and stability of the aircraft.

Disclosure of Invention

The invention aims to overcome the defects of large overall resistance, poor fuel economy and large noise in cabins and external fields of an airplane in the prior art.

The invention solves the technical problems by the following technical proposal:

The invention provides an airplane, which comprises a cylindrical airplane body and is characterized by further comprising a full-motion front wing arranged on the front section of the airplane body, an engine arranged above the tail section of the airplane body and a wing arranged on the middle and rear section of the airplane body, wherein the wing adopts an upper single wing with a supporting rod, one end of the supporting rod is connected to the abdomen of the airplane body, and the other end of the supporting rod is connected to the upper single wing.

Preferably, the distance between the connection position of the other end of the supporting rod and the upper single wing and the nearest endpoint of the upper single wing is between 55% and 75% of the half span length of the upper single wing.

Preferably, the engine is an open rotor engine.

Preferably, the upper single wing comprises a middle section wing and an outer section wing, the outer section wing is a trapezoid wing, the front edge of the outer section wing has a larger sweepback angle compared with the rear edge, and the sweepback angle difference of the two is not more than 10 degrees.

Preferably, a streamline oil storage cabin is hung near the separation surface of the outer section wing and the middle section wing, and the other end of the supporting rod is connected to the shell of the streamline oil storage cabin.

Preferably, the support rods adopt zero camber symmetrical laminar flow wing sections with the relative thickness between 10% and 13%.

Preferably, the middle section wing adopts a laminar flow wing profile with the relative thickness of between 12 and 13 percent, and the outer section wing adopts a laminar flow wing profile with the relative thickness of between 9 and 12 percent.

Preferably, the middle section wing is in a straight rectangular shape, and the dihedral angle of the middle section wing is 0 °.

Preferably, the dihedral angle of the outer segment wing is between 6 ° and 10 °.

Preferably, the tip to root ratio of the chord length of the outer section is between 0.45 and 0.75.

Preferably, the aspect ratio of the upper single wing is greater than 15.

Preferably, the aircraft further comprises a horizontal tail, the open rotor engine is arranged behind the blades of the open rotor engine, the open rotor engine is arranged on the upper airfoil surface of the horizontal tail, and the rotation plane of the blades is located behind the rear edge of the horizontal tail.

Preferably, vertical tails are respectively installed at left and right tips of the horizontal tail.

Preferably, the horizontal tail adopts a laminar flow airfoil with negative camber or zero camber.

Preferably, the full-motion front wing adopts a trapezoid wing with a sweepback angle within 10 degrees.

Preferably, the full-motion front wing adopts laminar flow wing sections with the relative thickness between 12% and 13%.

Preferably, the full-motion front wing is arranged as a lower single wing and has a dihedral angle of between 3 ° and 7 °.

Or the full-motion front wing is arranged as a middle single wing or an upper single wing and has a dihedral angle of 0 degrees.

On the basis of conforming to the common knowledge in the field, the above preferred conditions can be arbitrarily combined to obtain the preferred examples of the invention.

The invention has the positive progress effects that:

Compared with the prior art, the aircraft provided by the invention has the characteristics of low resistance and low noise, the fuel economy is obviously improved, the noise in the cabin is obviously reduced, and meanwhile, the aircraft provided by the invention also has excellent maneuverability and stability.

Drawings

Fig. 1 is a perspective view of an aircraft in accordance with a preferred embodiment of the present invention.

Fig. 2 is another perspective view of an aircraft in accordance with a preferred embodiment of the present invention.

FIG. 3 is a top view of an aircraft showing the upper winglet layout shape in accordance with a preferred embodiment of the invention.

Fig. 4 is a top view of an aircraft showing the upper winglet layout shape in accordance with another preferred embodiment of the invention.

Fig. 5 is a front view of an aircraft in accordance with a preferred embodiment of the present invention.

Fig. 6 is a schematic view of the upper, middle and lower single wing configurations of the full-motion front wing in an aircraft in accordance with a preferred embodiment of the present invention.

Detailed Description

The following detailed description of the preferred embodiments of the invention, taken in conjunction with the accompanying drawings, is given by way of illustration and not limitation, and any other similar situations are intended to fall within the scope of the invention.

In the following detailed description, directional terms, such as "left", "right", "upper", "lower", "front", "rear", etc., are used with reference to the directions described in the drawings. The components of embodiments of the present invention can be positioned in a number of different orientations and the directional terminology is used for purposes of illustration and is in no way limiting.

Referring to fig. 1-2, an aircraft according to a preferred embodiment of the present invention comprises a cylindrical fuselage 1, a full-motion front wing 3 disposed at the front section of the fuselage, an open rotor engine 9 disposed above the tail section of the fuselage, and a wing disposed at the middle and rear sections of the fuselage, wherein the wing employs an upper single wing 2 with a support bar 6, one end of the support bar 6 is connected to the belly of the fuselage, and the other end is connected to the upper single wing 2.

The invention mounts the open rotor engine 9 with superior fuel economy at the tail, and the wing does not need to hang the engine. The supporting rods 6 are utilized to greatly reduce the bending moment of the middle section of the wing during flight, so that the thickness of the wing can be reduced, shock resistance during flight is reduced, the induced resistance is reduced by the wing with the large aspect ratio, and the noise in the cabin is reduced by the layout of the tail crane engine. A quiet intrabay environment can also be obtained. The adoption of the full-motion front wing 3 is beneficial to improving the longitudinal stability of the aircraft and further improving the performance of the full aircraft.

It should be understood that the innovative features of the present invention directed to the aircraft layout are also applicable to power plants of the type that change open rotor engines to large bypass ratio turbofan engines, turboprop engines, electric propulsion bypass fans, etc., and achieve economy and performance due to the prior art. Of course, the open rotor engine is taken as an example for illustration, and simultaneously, the self characteristics of the open rotor engine and the excellent fuel economy and the unusual full-engine performance which can be realized by the organic combination of the aircraft layout design of the invention are also highlighted.

The combined configuration of the support wing and the open rotor engine adopted by the aircraft layout can be said to be that the wing profile with the highest lift-drag ratio level and the turbine engine with the lowest oil consumption level are organically combined in the subsonic aircraft field.

In particular, the support bars can act as a diagonal brace to reduce bending moment unloading of the wing, thereby enabling the wing to be designed with the following profile features, such as: the wing has the advantages of super-large aspect ratio, smaller relative thickness and slender and thin whole wing. The above-described profile features of the wing are optionally applicable to, or in combination with, the present invention. The wing profile features described above are extremely advantageous for the lift-drag ratio of an aircraft. The high aspect ratio of the wing can cause the induced resistance of the wing to decrease in inverse proportion; the airfoil section with smaller relative thickness can lead the airfoil to adopt a flat or small sweepback design, so that the shock resistance can be reduced to a conventional level; also, the planar profile of the wing, which is straight or designed with a small sweep angle, exactly matches the laminar flow airfoil, which helps to further significantly reduce the air friction resistance.

According to some preferred embodiments of the invention, the spacing between the connection location of the support bar to the upper winglet and the nearest end point on the upper winglet is between 55% and 75% of the half-span length of the upper winglet, or the connection location of the support bar to the upper winglet is approximately in the middle of the half-span of the upper winglet. In some preferred embodiments, one end of the support bar is connected to the fairing below the upper winglet, i.e. one end of the support bar is connected to the upper winglet via the fairing, in which case the connection location is understood to be where the fairing is located relative to the airfoil of the upper winglet.

Based on the above technical factors, on the basis of the aircraft according to the preferred embodiment of the invention, the design of the wing surface can be further adopted to obtain some more preferred embodiments of the invention, which can realize more excellent full-aircraft performance and in-flight performance.

On the other hand, open rotor engines, while having extremely low fuel consumption levels, have not been fully and most properly utilized due to their own drawbacks in many other respects. Specifically, the open rotor engine has the problems of larger blade diameter, heavier engine weight, higher vibration and noise level, safety caused by rotor explosion and the like. Therefore, if the open rotor engine is installed on the wing by adopting a conventional engine arrangement mode, on one hand, the relatively clean aerodynamic shape and large laminar flow area of the wing can be damaged, the structural dynamics risk of flutter is brought, the weight gain cost of the wing structure can be possibly paid, on the other hand, the noise in the passenger cabin near the rotating plane of the blade can be greatly influenced by the engine, and blade fragments thrown out during rotor blasting have potential dangers of endangering personnel safety in the cabin and key system pipelines in the aircraft body.

Aiming at the advantages and disadvantages of the open rotor engine in many aspects, the invention adopts a tail installation mode, so that the defects of the open rotor engine are avoided to a great extent, and the influence of external field noise brought by the engine can be reduced through more preferable designs, such as shielding of a vertical tail wing.

In the airplane of the embodiment, the airplane body can adopt a traditional cylindrical airplane body with a large slenderness ratio, and the section of the airplane body adopts a right circular shape or a nearly right circular shape with multiple tangent sections of arcs, a streamline nose and a spindle-shaped contracted tail, so that the loading space requirement is mainly met. The inner space of the wing can meet the arrangement requirement of the oil tank, and the wing can be provided with movable surfaces such as a trailing edge flap, a trailing edge flap and an aileron. According to some preferred embodiments, the wing is a high aspect ratio wing, i.e. the aspect ratio of the upper mono wing 2 may be greater than 15.

In some preferred embodiments of the present invention, the open rotor engine may be installed in the upper part of the horizontal tail wing, and the open rotor engine needs a relatively large-overhanging and relatively heavy-structured engine frame due to the large blade diameter.

Furthermore, the rear-mounted scheme of the open rotor engine is adopted, so that the gravity center of the airplane is biased, the horizontal tail force arm is relatively short, and the horizontal tail stabilizer cannot be designed into a full-motion form because the horizontal tail is also used as an engine frame, so that the longitudinal operation stability and trimming capability of the airplane can be reduced to a certain extent. Therefore, the full-motion front wing is additionally arranged on the front fuselage according to the invention, so that the defects of the aircraft in longitudinal operation stability and trimming capability are overcome.

It should also be appreciated that while a three-shot aircraft configuration is illustrated in the figures, the above-described innovative layout of the present invention is equally applicable to a two-shot aircraft configuration.

In some preferred embodiments of the present invention, further innovative designs are made to the aircraft wing to further enhance aircraft performance. The planar layout of the upper mono-wing 2 of some preferred embodiments of the present invention is shown with reference to figure 3 in which the middle wing 21 is a straight rectangular wing and the outer wing 22 is a trapezoidal wing with a trailing edge that is straight, a leading edge that has a small sweep angle (not more than 10 deg.) and can fit a streamlined low drag wing tip.

According to other preferred embodiments of the present invention, in order to further reduce transonic shock resistance of the wing and reduce aerodynamic design difficulty, the planar shape of the wing may be increased by a sweepback angle of not more than 10 ° on the basis of the embodiment in which the middle wing 21 is a flat rectangular wing, as shown in fig. 4.

Preferably, the tip root ratio of the chord length of the outer section wing 22 is 0.45-0.75, the airfoil of the wing middle section wing 21 adopts a laminar airfoil with the relative thickness of 12-13%, and the airfoil of the outer section wing 22 adopts a laminar airfoil with the relative thickness of 9-12%. The root of the middle wing is projected on the front view of the airplane, can be integrally positioned above the straight section of the airplane body and the like, and is fused with the appearance of the airplane body through the wing body fairing.

According to some preferred embodiments of the present invention, as shown with reference to fig. 1 and 5, a streamline oil storage tank is hung near the separation surface of the outer wing 22 and the middle wing 21, and the other end of the support bar 6 is connected to the outer shell of the streamline oil storage tank. The oil storage compartment may be a nacelle. The separating surfaces referred to herein, i.e. the junction of the outer and middle section wings 22 and 21, it should be noted that the outer and middle section wings 22 and 21 referred to herein are merely descriptive of different locations on the wing airfoil and do not necessarily represent separate parts.

Preferably, the nacelle cover is connected to the support bar via a joint, which design avoids the problem of aerodynamic interference due to too narrow an airflow path caused by the direct connection of the support bar to the wing. The oil storage nacelle also has the unloading function of reducing the bending moment of the middle wing. According to the operational stability characteristics of the aircraft, the dihedral angle of the middle section wing 21 of the aircraft is 0 DEG, and the dihedral angle of the outer section wing 22 is 6 DEG to 10 deg. It is further preferred that the middle wing 21 adopts a laminar wing profile having a relative thickness of between 12% and 13%, and the outer wing 22 adopts a laminar wing profile having a relative thickness of between 9% and 12%.

Alternatively, referring to fig. 1 and 5, one end of the supporting rod 6 is connected to a mechanism joint on the belly of the fuselage, and the other end is connected to a structure joint of the oil storage nacelle under the wing, so that the supporting rod 6 and the middle section of the wing form a triangular truss structure, and bending moment and stress during flying of the middle section of the wing can be effectively reduced. The support rods 6 can adopt zero-camber symmetrical laminar flow wing sections with the relative thickness of 10-13%.

Referring to fig. 1-2, according to some preferred embodiments of the present invention, the aircraft further includes a horizontal tail 4, the open rotor engine 9 is aft of the blades, the open rotor engine 9 is disposed on an upper airfoil surface of the horizontal tail 4, and a plane of rotation of the blades is behind a trailing edge of the horizontal tail 4. Further, vertical tail 5 may be mounted to the left and right tips of the horizontal tail 4, respectively.

Wherein the horizontal rear wing 4 comprises a horizontal stabilizer and an elevator, the horizontal rear wing 4 is installed at both sides of the tail section of the fuselage, and preferably adopts a laminar wing profile with negative camber or zero camber for longitudinal trimming, manipulation and stabilization of the aircraft, and simultaneously functions as an engine mount, so that the engine can be directly installed on the structure of the horizontal rear wing 4, and the elevator is arranged at the rear edge of the horizontal rear wing 4 at the inner side of the nacelle. The vertical tail 5 includes a vertical stabilizer and a rudder, and is mounted on the tip of the horizontal tail 4. The trailing edge of the vertical tail 5 is provided with a rudder. The vertical tail 5 is used for course trimming, steering and stabilization of the aircraft. Meanwhile, the vertical tail 5 can effectively shield the range of more than 60% of the rotation plane of the fan blade of the open rotor engine, thereby effectively shielding the noise influence of the fan and playing a role in reducing noise. In addition, the left and right vertical tails are mutually backed up, and the influence of flying out and damaging the vertical tail 5 of the fan blade of the engine on the flight safety can be reduced.

And, the tail suspension type rotor engine 9 has great potential in improving fuel economy and reducing carbon dioxide emission compared with a turbofan engine with the same thrust level, and can realize extremely high theoretical bypass ratio design by removing a fan housing, and the fuel consumption rate can be reduced by 25-30% on the basis of the turbofan engine.

According to some preferred embodiments of the present invention, the full-motion front wing 3 (which may also be referred to as a full-motion duck wing) may employ a trapezoidal wing with a straight or small sweep angle within 10 ° of 1/4 chord line, and may be equipped with a low drag wing tip, and the full-motion front wing 3 employs a laminar airfoil with a relative thickness of between 12% -13%. It is further preferred that the full-motion front wing 3 is provided as a lower single wing and has an dihedral angle between 3 deg. -7 deg., or as a middle single wing or an upper single wing and has an dihedral angle of 0 deg.. The full-motion front wing 3 contributes to further improving the pitch trim and handling characteristics of the aircraft. The full-moving front wing with the configuration is stalled before the main wing when the angle of attack is large, so that the aerodynamic performance of the aircraft with the large angle of attack is improved, and the aircraft has more reasonable longitudinal stability.

According to some preferred embodiments of the present invention, the height position of the full-motion front wing 3 relative to the front section of the fuselage may adopt three options of a lower single wing, a middle single wing and an upper single wing, as shown in fig. 6, the full-motion front wing 3 adopting an upper single wing, a middle single wing and a lower single wing configuration is respectively shown from top to bottom. If the lower single wing is adopted, the front wing has an dihedral angle of 3-7 degrees, and the rest height positions can adopt dihedral angles of 0 degrees. For the configuration of the lower single wing and the upper single wing, the root of the full-motion front wing 3 can be fused and transited with the shape of the machine body by adopting a fairing.

With reference to figures 1-2, a trailing edge lift device 7 and an aileron 8 are mounted on the trailing edge of the upper mono wing 2 of the wing for lift augmentation and roll manipulation and trimming during flight of the aircraft.

According to some preferred embodiments of the invention, the landing gear system employs a nose three-point landing gear 10 with nose gear wheels located below the nose section of the fuselage and main landing gear located below the belly gear pod bulge. The landing gear bay bulge provides space for the main landing gear to retract and retract while being connected to the wing support bar 6.

While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that these are by way of example only, and the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the principles and spirit of the invention, but such changes and modifications fall within the scope of the invention.

Claims (10)

1. The aircraft comprises a cylindrical airframe, and is characterized by further comprising a full-motion front wing arranged on the front section of the airframe, an engine arranged above the tail section of the airframe and a wing arranged on the middle and rear section of the airframe, wherein the wing adopts an upper single wing with a supporting rod, one end of the supporting rod is connected to the belly of the airframe, the other end of the supporting rod is connected to the upper single wing, and the engine is an open rotor engine;

the aircraft further comprises a horizontal tail, the open rotor engine is arranged behind the blades of the open rotor engine, the open rotor engine is arranged on the upper surface of the horizontal tail, and the rotation plane of the blades is positioned behind the rear edge of the horizontal tail;

The full-motion front wing adopts a trapezoid wing with a sweepback angle within 10 degrees, and the full-motion front wing adopts a laminar wing section with a relative thickness of 12% -13%;

The full-acting front wing is arranged as a lower single wing and has an dihedral angle of 3-7 degrees, or is arranged as a middle single wing or an upper single wing and has an dihedral angle of 0 degrees.

2. The aircraft of claim 1, wherein a distance between a connection location of the other end of the support bar to the upper wing and a nearest endpoint of the upper wing is between 55% and 75% of a half span length of the upper wing.

3. The aircraft of claim 1, wherein the upper mono-wing comprises a mid-section wing and an outer-section wing, the outer-section wing being a trapezoidal wing, the leading edge of the outer-section wing having a greater sweep angle than the trailing edge, and the sweep angles being no more than 10 ° apart.

4. An aircraft according to claim 3, wherein a streamlined oil storage tank is suspended adjacent the separation surface of the outer wing and the middle wing, and the other end of the support rod is connected to the outer shell of the streamlined oil storage tank.

5. The aircraft of claim 4, wherein the support struts employ zero camber symmetrical laminar flow airfoils having a relative thickness of between 10% -13%.

6. An aircraft according to claim 3, wherein the middle wing employs a laminar flow profile having a relative thickness of between 12% and 13% and the outer wing employs a laminar flow profile having a relative thickness of between 9% and 12%.

7. An aircraft according to claim 3, wherein the midspan wing has a straight rectangular shape, the dihedral of the midspan wing is 0 °, the dihedral of the outer wing is between 6 ° and 10 °, and the root-to-tip ratio of the chord length of the outer wing is between 0.45 and 0.75.

8. An aircraft according to claim 1, wherein the aspect ratio of the upper mono-wing is greater than 15.

9. The aircraft of claim 1, wherein vertical tails are respectively mounted to left and right tips of the horizontal tails.

10. The aircraft of claim 1, wherein the tailplane employs a negative camber or zero-camber laminar airfoil.