CN116280166A - Tandem wing-continuous wing ground effect aircraft - Google Patents

Abstract

A tandem wing-continuous wing ground effect aircraft comprises a fuselage, a front wing, a rear wing, a continuous wing, an engine, a tail wing and a pontoon; the height position relation of the front wing and the rear wing meets the following conditions: the ratio of the water-leaving surface height of the front wing to the average aerodynamic chord length of the front wing in the cruising state is equal to the ratio of the water-leaving surface height of the rear wing to the average aerodynamic chord length of the rear wing; the front-rear position relationship of the front wing and the rear wing satisfies: the ratio of the front-to-back distance of the average aerodynamic chord focus of the front wing from the center of gravity of the aircraft to the front-to-back distance of the average aerodynamic chord focus of the rear wing from the center of gravity of the aircraft is equal to the square of the ratio of the average aerodynamic chord length of the rear wing to the average aerodynamic chord length of the front wing. According to the invention, through reasonably configuring the height position relation and the front-rear position relation of the front wing and the rear wing, the longitudinal operation stability of the whole aircraft is enhanced, the technical problem that the aircraft is easy to run away due to the additional pitching moment increment generated when the flying height of the traditional layout ground effect aircraft is changed is solved, the transverse heading maneuverability of the whole aircraft is greatly enhanced, the carrying capacity is improved, and higher carrying efficiency is realized.

Description

Tandem wing-continuous wing ground effect aircraft

Technical Field

The invention belongs to the technical field of aerodynamic layout design of aircrafts, and particularly relates to a tandem wing-continuous wing ground effect aircraft.

Background

When an aircraft flies close to the ground or water surface, the lift-drag ratio of the aircraft increases, and the phenomenon of resistance reduction is induced, which is called ground effect. There is a range of flying heights that produce the ground effect, known as ground effect areas. The ground effect aircraft is a novel transportation tool which utilizes the ground effect principle to fly in a ground effect area close to the ground or the water surface and has the performance between that of a ship and a conventional aircraft. The ground effect aircraft has wide application prospect in the field of army and civil engineering due to the characteristics of high cruising speed, high lift-drag ratio, high carrying efficiency, good economy and the like.

However, when the ground effect aircraft flies in the ground effect area, the change of flying height can cause the change of aerodynamic force of the whole aircraft, and for the ground effect aircraft with the traditional layout such as single main wing, the aerodynamic force change caused by the change of flying height is easy to generate additional pitching moment increment, thereby causing the technical problem that the aircraft is easy to run away and affecting the flying safety.

In addition, because the height range of the ground effect area is smaller and is often equal to or smaller than the chord length of the wing, for the ground effect aircraft cruising in the ground effect area, the traditional layout such as a single main wing is adopted, and the main wing has overlong relative flight height, so that the maneuvering space is limited, and the maneuvering in the transverse heading cannot be realized in the ground effect area in a mode such as rolling of the fuselage, so that the maneuvering in the transverse heading is poor.

Disclosure of Invention

The invention solves the technical problems that: the method has the advantages that the defects of the prior art are overcome, the tandem wing-continuous wing ground effect aircraft is provided, the longitudinal operation stability of the whole aircraft is enhanced by reasonably configuring the height position relationship and the front-rear position relationship of the front wing and the rear wing, the technical problem that the aircraft is easy to run away due to the fact that additional pitching moment increment is generated when the flying height of the traditional layout ground effect aircraft changes is solved, and the flying safety is ensured; through the layout form that the front wing is arranged at the lower part and the rear wing is arranged at the upper part, and the front wing is short and the rear wing is long, the transverse heading maneuver can be realized in the cruising of the ground effect area in a rolling mode of the machine body, and the transverse heading maneuverability of the whole machine is greatly enhanced; the closed wing configuration is realized through the serial wing-continuous wing layout form, so that the aerodynamic efficiency is further improved, the weight of an aircraft is reduced, the carrying capacity is improved, and the higher carrying efficiency is realized.

The technical scheme provided by the invention is as follows:

a tandem wing-continuous wing ground effect aircraft, comprising: fuselage, front wing, rear wing and connecting wing;

the front wing is arranged below the front part of the machine body, and the rear wing is arranged above the rear part of the machine body; the wing sections of the front wing and the rear wing are the same, the slightly root ratio is the same, the aspect ratio is the same, and the span length of the front wing is smaller than that of the rear wing;

the height position relation between the front wing and the rear wing satisfies the following conditions: the ratio of the water leaving surface height h1 of the front wing to the average aerodynamic chord length c1 of the front wing in the cruising state is equal to the ratio of the water leaving surface height h2 of the rear wing to the average aerodynamic chord length c2 of the rear wing;

the front-rear position relationship between the front wing and the rear wing satisfies the following conditions: the distance between the average aerodynamic chord focus of the front wing and the center of gravity of the aircraft in the axial direction is d1, the distance between the average aerodynamic chord focus of the rear wing and the center of gravity of the aircraft in the axial direction is d2, and the ratio of d1 to d2 is equal to the square of the ratio of c2 to c 1;

the connecting wing is connected with the front wing and the rear wing, two ends of the connecting wing are respectively and fixedly connected with the wing tip of the front wing and the middle part of the rear wing, and the chord lines of any airfoil section of the connecting wing are parallel to the axis of the fuselage.

Further, the aircraft also comprises an engine, a tail wing and a pontoon;

the engine is arranged at the front part of the machine body and is axially positioned in front of the front wing; the tail wing is arranged at the tail part of the machine body; pontoons are also arranged at the two ends of the front wing.

Furthermore, the fuselage is in an aircraft fuselage-hull fusion layout, the upper half part of the fuselage is the aircraft fuselage, the lower half part of the fuselage is the hull, and the middle part of the hull is provided with a broken step;

the hull chord line in the first distance L1 before the step breaking is parallel to the axis of the machine body, and the bottom of the cross section is V-shaped; after the step is broken, the chord line of the hull in the second distance L2 forms an included angle alpha with the axis of the fuselage, and the bottom of the cross section is gradually transited from V shape to straight shape; the tail chord line of the ship body forms an included angle beta with the axis of the ship body, and the bottom of the cross section is straight.

Further, the first distance L1 is not less than 1.5 times the fuselage width; the second distance L2 is not greater than 0.5 times the overall length of the aircraft.

Further, the value range of the included angle alpha is 7-9 degrees; the value range of the included angle beta is alpha less than or equal to beta less than or equal to 45 degrees.

Furthermore, the front wing is a trapezoid wing, the root ratio is 0.4-0.5, and the rear edge of the front wing is provided with a front wing flap.

Further, the rear wing is a trapezoid wing, and the root ratio is 0.4-0.5.

Further, the wing profile of the connecting wing is a symmetrical wing profile.

Further, the pontoon is arranged below the wing tip of the front wing; the tail fin is a V-shaped tail fin and is arranged above the tail of the machine body, and the included angle between the tail fins is not more than 90 degrees.

Further, the mounting height of the engine is higher than the front wing and lower than the rear wing; the rear part of the engine is provided with an airflow direction adjusting device which can deflect the airflow direction of the nozzle of the engine to enable the airflow to flow over the front wing or flow to a power air cushion cavity below the front wing;

the power air cushion cavity is a cavity formed by the lower part of the machine body, the lower wing surface of the front wing, the downward deflected front wing flap, the pontoon and the water surface.

The tandem wing-continuous wing ground effect aircraft provided by the invention has the following beneficial effects:

(1) According to the tandem wing-continuous wing ground effect aircraft, the altitude position relation and the front-rear position relation of the front wing and the rear wing are reasonably configured, so that the ground effect aircraft does not generate additional pitching moment increment when the cruising flying height is changed, the longitudinal operation stability of the whole aircraft is enhanced, the technical problem that the aircraft is easy to run away due to the additional pitching moment increment when the flying height of the traditional layout ground effect aircraft is changed is solved, and the flying safety is ensured.

(2) According to the tandem wing-continuous wing ground effect aircraft, the front wing is arranged at the lower part, the rear wing is arranged at the upper part, the front wing is short, the rear wing is long, the transverse heading maneuver can be realized in the cruising process in the ground effect area in a rolling mode of the aircraft body, and the transverse heading maneuver of the whole aircraft is greatly enhanced.

(3) According to the tandem wing-continuous wing ground effect aircraft, the closed wing configuration is realized through the tandem wing-continuous wing layout, so that the induced resistance is further reduced, the lift-drag ratio is improved, and the aerodynamic efficiency of the ground effect aircraft is improved; meanwhile, the wing is smaller in size, lighter in structural weight and larger in rigidity, the weight of the aircraft is further reduced, the carrying capacity is improved, and higher carrying efficiency is realized.

Drawings

FIG. 1 is a schematic top view of a tandem wing-continuous wing ground effect aircraft of the present invention;

FIG. 2 is a schematic side view of a tandem wing-continuous wing ground effect aircraft of the present invention;

FIG. 3 is a schematic front view of a tandem wing-continuous wing ground effect aircraft of the present invention;

FIG. 4 is a schematic illustration of the average aerodynamic chord length of the front and rear wings versus the height from the water surface in accordance with the present invention;

FIG. 5 is a schematic view of the average aerodynamic chord focal point of the front wing and the rear wing of the present invention, the forward and aft distance from the center of gravity of the aircraft, and the average aerodynamic chord length;

FIG. 6 is a schematic cross-sectional view of the fuselage of the present invention in a first distance L1 before the break, and in a second distance L2 after the break.

Description of the reference numerals

1-a fuselage; 1-1-breaking; 2-an engine; 2-1-an air flow regulating device; 3-front wing; 3-1-front wing flaps; 4-connecting wings; 5-rear wing; 6-tail fin; 7-pontoon.

Detailed Description

The features and advantages of the present invention will become more apparent and clear from the following detailed description of the invention.

The word "exemplary" is used herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are illustrated in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

As shown in fig. 1 to 6, the invention provides a tandem wing-continuous wing ground effect aircraft, which comprises a fuselage 1, a front wing 3, a rear wing 5, a continuous wing 4, an engine 2, a tail wing 6 and a pontoon 7, wherein the specific composition is shown in fig. 1.

The front wing 3 is installed below the front of the fuselage 1, and the rear wing 5 is installed above the rear of the fuselage 1, see fig. 2; the wing profiles of the front wing 3 and the rear wing 5 are the same, the slightly root ratio is the same, the aspect ratio is the same, and the extension length of the front wing 3 is smaller than that of the rear wing 5; the height position relationship between the front wing 3 and the rear wing 5 satisfies: the ratio of the water-leaving surface height h1 of the front wing 3 to the average aerodynamic chord length c1 of the front wing 3 in the cruising state is equal to the ratio of the water-leaving surface height h2 of the rear wing 5 to the average aerodynamic chord length c2 of the rear wing 5, see fig. 4; the front-rear positional relationship between the front wing 3 and the rear wing 5 satisfies: the ratio of the front-rear distance d1 of the average aerodynamic chord focal point of the front wing 3 from the center of gravity of the aircraft to the front-rear distance d2 of the average aerodynamic chord focal point of the rear wing 5 from the center of gravity of the aircraft is equal to the square of the ratio of the average aerodynamic chord length c2 of the rear wing 5 to the average aerodynamic chord length c1 of the front wing 3, see fig. 5;

the connecting wing 4 is fixedly connected with the wing tip of the front wing 3 and the middle part of the rear wing 5, and the chord line of any airfoil section of the connecting wing 4 is parallel to the axis of the fuselage 1.

In a preferred embodiment, the fuselage 1 is an aircraft fuselage-hull fusion arrangement, the upper part is an aircraft fuselage, the lower part is a hull, and the middle part of the hull is provided with a broken step 1-1, see fig. 2; the chord line of the hull in a first distance L1 (not less than 1.5 times of the width of the fuselage) before the step breaking 1-1 is parallel to the axis of the fuselage 1, and the bottom of the cross section is V-shaped; after the step is broken by 1-1, the chord line of the hull in the second distance L2 (the second distance L2 is not more than 0.5 times of the total length of the aircraft) forms an included angle alpha (7-9 degrees) with the axis of the aircraft body 1, and the bottom of the cross section is gradually transited from a V shape to a straight shape; the tail chord line of the ship body forms an included angle beta (alpha is more than or equal to beta is less than or equal to 45 degrees) with the axis of the machine body 1, and the bottom of the cross section is straight, as shown in figure 6.

In a preferred embodiment, the front wing 3 is a trapezoid wing, the tip root ratio is 0.4-0.5, and the rear edge of the front wing 3 is provided with a front wing flap 3-1, see fig. 1.

In a preferred embodiment, the rear wing 5 is a trapezoidal wing, and the root ratio is 0.4 to 0.5.

In a preferred embodiment, the airfoil of the connecting wing 4 is a symmetrical airfoil.

In a preferred embodiment, the pontoon 7 is mounted slightly below the front wing 3, see fig. 1.

In a preferred embodiment, the engine 2 is mounted on the front of the fuselage 1 in front of the front wing 3, the engine 2 being mounted at a higher level than the front wing 3 and lower than the rear wing 5; the rear part of the engine 2 is provided with an airflow direction adjusting device 2-1 which can deflect the airflow direction of the nozzle of the engine to enable the airflow to flow over the front wing 3 or flow to a power air cushion cavity below the front wing 3;

the power air cushion cavity refers to a cavity formed by the lower part of the machine body 1, the lower airfoil surface of the front wing 3, the front wing flap 3-1 deflected downwards, the pontoon 7 and the water surface.

In a preferred embodiment, the tail wing 6 is a V-shaped tail wing, and is mounted above the tail of the fuselage 1, and the included angle between the tail wings is not more than 90 °.

The principle of the longitudinal stability characteristics of the tandem wing-continuous wing ground effect aircraft is as follows:

the aerodynamic characteristics of the front wing, the rear wing, the lift coefficient and the like under the same state are consistent by controlling the front wing and the rear wing to adopt the same wing section, the same root ratio and the same aspect ratio; the ratio of the average aerodynamic chord length of the front wing to the average aerodynamic chord length of the rear wing to the height from the water surface is equal during cruising through the design of the height position relationship, so that the aerodynamic characteristics of the front wing and the rear wing in a ground effect area are ensured to be consistent; and finally, the front and rear position relations of the front wing and the rear wing are reasonably configured, so that the aerodynamic force increment generated by the front wing and the rear wing of the ground effect aircraft is equal in moment around the gravity center and opposite in direction, and can be mutually offset, the whole aircraft is ensured not to generate additional pitching moment increment when the flying height of the ground effect aircraft changes, the longitudinal stability operating characteristic is enhanced, and the flying safety is ensured.

The principle of the transverse heading maneuver characteristics of the tandem wing-continuous wing ground effect aircraft is as follows:

through the layout form that the front wing is arranged below and the rear wing is arranged above, and the front wing is short and the rear wing is long, the ground effect aircraft can realize the rolling of the airframe in the ground effect area, and the aerodynamic force born by the ground effect aircraft can be decomposed into centripetal component force of the transverse heading at the moment, so that the ground effect aircraft can realize the transverse heading maneuver. Because the front wing is short, the layout form does not need to worry about the problem that the airplane body roll caused by overlong main wings in the traditional layout such as a single main wing easily causes the water to be taken by the wings so as to influence the flight safety, and the layout form can realize a larger airplane body roll angle, so that the transverse maneuverability is greatly enhanced.

In this embodiment, the front airfoil 3 and the rear airfoil 5 both use the same airfoil (preferably, a airfoil with a flatter lower airfoil, such as NACA4412 airfoil, may be used), and the root ratio is 0.5, and the aspect ratio is 7.5; the front wing 3 has a spreading length of 18.75m and an average aerodynamic chord length of 2.5m; the forward sweep angle of the rear wing 5 is 30 degrees, the extension length is 37.65m, and the average aerodynamic chord length is 5.01m; the height of the front wing 3 from the water surface is 3.75m, and the height of the rear wing 5 from the water surface is 7.52m in the cruising state; the total length of the aircraft is 41.2m, the gravity center is located at 50.9% of the whole aircraft, the average aerodynamic chord focus of the front wing 3 is 9.38m from the front to back of the gravity center of the aircraft, and the average aerodynamic chord focus of the rear wing 5 is 2.33m from the front to back of the gravity center of the aircraft. The airfoil 4 adopts a symmetrical airfoil shape, and the airfoil shape is NACA0009. The width of the machine body is 5m, the first distance L1 before the broken step 1-1 is 12.1m, the second distance L2 after the broken step 1-1 is 9.31m, the included angle alpha is 9 degrees, and the included angle beta is 25 degrees. The included angle between the tail wings is 60 degrees.

The parameters are obtained through detailed theoretical calculation and numerical analysis so as to realize reasonable design of aerodynamic parameters of the aircraft.

In the present invention, forward is the direction along the fuselage axis from the tail of the aircraft to the head of the aircraft, and correspondingly, aft is the direction along the fuselage axis from the head of the aircraft to the tail of the aircraft.

The invention has been described in detail in connection with the specific embodiments and exemplary examples thereof, but such description is not to be construed as limiting the invention. It will be understood by those skilled in the art that various equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its embodiments without departing from the spirit and scope of the present invention, and these fall within the scope of the present invention. The scope of the invention is defined by the appended claims.

What is not described in detail in the present specification is a well known technology to those skilled in the art.

Claims (10)

1. A tandem wing-continuous wing ground effect aircraft, comprising: a fuselage (1), a front wing (3), a rear wing (5) and a connecting wing (4);

the front wing (3) is arranged below the front part of the machine body (1), and the rear wing (5) is arranged above the rear part of the machine body (1); the wing shape of the front wing (3) is the same as that of the rear wing (5), the root ratio is the same, the aspect ratio is the same, and the extension length of the front wing (3) is smaller than that of the rear wing (5);

the height position relation between the front wing (3) and the rear wing (5) is as follows: the ratio of the water leaving surface height h1 of the front wing (3) to the average aerodynamic chord length c1 of the front wing (3) is equal to the ratio of the water leaving surface height h2 of the rear wing (5) to the average aerodynamic chord length c2 of the rear wing (5) in the cruising state;

the front-rear position relationship between the front wing (3) and the rear wing (5) is as follows: the distance between the average aerodynamic chord focus of the front wing (3) and the center of gravity of the aircraft in the axial direction is d1, the distance between the average aerodynamic chord focus of the rear wing (5) and the center of gravity of the aircraft in the axial direction is d2, and the ratio of d1 to d2 is equal to the square of the ratio of c2 to c 1;

the connecting wing (4) is connected with the front wing (3) and the rear wing (5), two ends of the connecting wing are respectively and fixedly connected with the wing tip of the front wing (3) and the middle part of the rear wing (5), and the chord lines of any airfoil section of the connecting wing (4) are parallel to the axis of the machine body (1).

2. A tandem wing-continuous wing ground effect aircraft according to claim 1, wherein: the device also comprises an engine (2), a tail wing (6) and a pontoon (7);

the engine (2) is arranged at the front part of the machine body (1) and is axially positioned in front of the front wing (3); the tail wing (6) is arranged at the tail part of the machine body (1); pontoons (7) are arranged at the two ends of the front wing (3).

3. A tandem wing-continuous wing ground effect aircraft according to claim 1 or 2, characterized in that: the fuselage (1) is in an aircraft fuselage-hull fusion layout, the upper half part of the fuselage (1) is an aircraft fuselage, the lower half part of the fuselage is a hull, and a broken step (1-1) is arranged in the middle of the hull;

the chord line of the ship body in the first distance L1 before the step breaking (1-1) is parallel to the axis of the machine body (1), and the bottom of the cross section is V-shaped; the chord line of the ship body in the second distance L2 forms an included angle alpha with the axis of the machine body (1) after the step (1-1) is broken, and the bottom of the cross section is gradually transited from V shape to straight shape; the tail chord line of the ship body and the axis of the machine body (1) form an included angle beta, and the bottom of the cross section is straight.

4. A tandem wing-continuous wing ground effect aircraft according to claim 3, wherein: the first distance L1 is not less than 1.5 times of the width of the machine body; the second distance L2 is not greater than 0.5 times the overall length of the aircraft.

5. A tandem wing-continuous wing ground effect aircraft according to claim 3, wherein: the value range of the included angle alpha is 7-9 degrees; the value range of the included angle beta is alpha less than or equal to beta less than or equal to 45 degrees.

6. A tandem wing-continuous wing ground effect aircraft according to claim 1 or 2, characterized in that: the front wing (3) is a trapezoid wing, the root ratio is 0.4-0.5, and a front wing flap (3-1) is arranged at the rear edge of the front wing (3).

7. A tandem wing-continuous wing ground effect aircraft according to claim 1 or 2, characterized in that: the rear wing (5) is a trapezoid wing, and the root ratio is 0.4-0.5.

8. A tandem wing-continuous wing ground effect aircraft according to claim 1 or 2, characterized in that: the wing profile of the connecting wing (4) is a symmetrical wing profile.

9. A tandem wing-continuous wing ground effect aircraft according to claim 2, wherein: the pontoon (7) is arranged below the wing tip of the front wing (3); the tail wing (6) is a V-shaped tail wing and is arranged above the tail part of the machine body (1), and the included angle between the tail wings is not more than 90 degrees.

10. A tandem wing-continuous wing ground effect aircraft according to claim 1 or 2, characterized in that: the mounting height of the engine (2) is higher than the front wing (3) and lower than the rear wing (5); the rear part of the engine (2) is provided with an airflow direction adjusting device (2-1) which can deflect the airflow direction of the nozzle of the engine to enable the airflow to flow over the front wing (3) or flow to a power air cushion cavity below the front wing (3);

the power air cushion cavity is a cavity formed by the lower part of the machine body (1), the lower airfoil surface of the front wing (3), the downward deflected front wing flap (3-1), the pontoon (7) and the water surface.

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