CN115541174A

CN115541174A - Large-size dynamic derivative test model structure

Info

Publication number: CN115541174A
Application number: CN202211506404.9A
Authority: CN
Inventors: 刘淑丽; 李思朋; 卜忱; 陈昊; 刘上
Original assignee: AVIC Aerodynamics Research Institute
Current assignee: AVIC Aerodynamics Research Institute
Priority date: 2022-11-29
Filing date: 2022-11-29
Publication date: 2022-12-30
Anticipated expiration: 2042-11-29
Also published as: CN115541174B

Abstract

A large-size dynamic derivative test model structure belongs to the technical field of aircraft design. The invention provides a large-size dynamic derivative test model structure which comprises a fuselage, wings and a slide rail, wherein the fuselage comprises a front fuselage, a middle fuselage and a rear fuselage, and the length of the fuselage and the maximum extension length of the wings do not exceed 40% of the width of a wind tunnel test section; the front machine body, the middle machine body and the rear machine body are connected in sequence; the wings are connected with the middle fuselage; a sliding rail is assembled on the wing; the connecting part of the slide rail and the wing is defined as a metal front-section connecting seat of the slide rail, the metal front-section connecting seat of the slide rail is of a hollow structure, and the rest part of the slide rail is defined as a carbon fiber rear section of the slide rail; under the condition of a large number of levels, the model has the mass and the rotational inertia as small as possible, the coincidence of the reference center of the airplane model and the actual mass center of the model is ensured, and the method has important significance for reducing the damage of model vibration to mechanisms in the wind tunnel in the test process and improving the precision of wind tunnel test data.

Description

Large-size dynamic derivative test model structure

Technical Field

The invention belongs to the technical field of aircraft design, particularly relates to a pneumatic layout design of aircraft design, and particularly relates to a large-size dynamic derivative test model structure.

Background

The dynamic derivative, also called the stability derivative, describes the aerodynamic characteristics of the aircraft in a maneuver and in a disturbance. Are the essential aerodynamic parameters in the design of the aerodynamic performance of the aircraft, the control system and the overall design. At different stages of aircraft design, as the aerodynamic profile is adjusted, the designer must know the dynamic aerodynamic characteristics and gradually improve them to improve the flight performance and flight quality index of the final profile. The interpretation of the aerodynamic stability data must be of concern and its impact on the accuracy of the system integration design assessed.

The conventional methods for wind tunnel dynamic derivative tests are a free vibration method and a forced vibration method, and are used for measuring the force acting on the model and measuring the motion parameters of the model. Because the test is carried out under the condition of vibration, the special requirement on the dynamic derivative test model is that the mass and the rotational inertia of the dynamic derivative test model are as small as possible so as to reduce the inertia force and the inertia moment, improve the natural frequency of a balance model system and be beneficial to improving the measurement precision. Therefore, molds are typically machined from lightweight, low density materials. In addition, the coincidence of the mass center of the model and the rotation center of the test mechanism is ensured as much as possible, so that extra errors caused by the generation of complex vibration modes are avoided.

For a large-size dynamic derivative test model, namely a dynamic derivative test model with the span of an airplane model machine reaching 3m magnitude and above, on the premise of meeting the strength and rigidity, the design is reasonable, and the mass and the rotational inertia are reduced. Meanwhile, in order to ensure that the rotation center of the test mechanism, the actual mass center of the model and the balance calibration center are overlapped as much as possible, the whole weight distribution of the model is also required to be considered during design. A perfect large-size dynamic derivative test model design scheme is a design guidance thought which is urgently needed by the current wind tunnel test.

Disclosure of Invention

The invention aims to provide a model with the mass and the moment of inertia as small as possible under the condition of a large number of levels. And to ensure that the reference center of the aircraft model coincides with the actual center of mass of the model, a brief summary of the invention is provided below in order to provide a basic understanding of some aspects of the invention. It should be understood that this summary is not an exhaustive overview of the invention. It is not intended to determine the key or important part of the present invention, nor is it intended to limit the scope of the present invention.

The technical scheme of the invention is as follows:

a large-size dynamic derivative test model structure comprises a fuselage, wings and a slide rail, wherein the fuselage comprises a front fuselage, a middle fuselage and a rear fuselage, and the length of the fuselage and the maximum extension length of the wings do not exceed 40% of the width of a wind tunnel test section; the front machine body, the middle machine body and the rear machine body are connected in sequence; the wings are connected with the middle fuselage; a sliding rail is assembled on the wing; the connecting part of the slide rail and the wing is defined as a metal front-section connecting seat of the slide rail and is made of metal materials, the metal front-section connecting seat of the slide rail is of a hollow structure, and the rest part of the slide rail is defined as a carbon fiber rear section of the slide rail and is made of carbon fiber materials;

the front fuselage comprises a front fuselage skeleton, a carbon fiber reinforced beam, a front fuselage skin and a nose balancing weight;

the rear end of the front fuselage framework is provided with an interface for connecting with the middle fuselage; the front machine body framework is provided with a carbon fiber reinforced beam; the front end of the front machine body is provided with a machine head balancing weight; the front fuselage skin is coated on the front fuselage skeleton;

the wing comprises a wing framework, a wing lapping framework, a wing tip and a wing skin; the wing lapping framework is lapped with the wing framework; the wing framework is connected with the wing tip of the wing; the wing skin is coated on the wing;

a hair-styling room is arranged below the wings, the hair-styling room is of a smooth annular structure, foam is used as a sandwich supporting material, a carbon fiber skin is used as the appearance, a hair-styling flow deflector is bonded at a corresponding interface position on the hair-styling room, the hair-styling flow deflector is provided with a sharp surface, and the hair-styling flow deflector is machined by using a metal material;

the middle fuselage comprises a middle fuselage framework, a middle fuselage skin, a taper sleeve and a balance; the front end of the middle machine body framework is provided with a taper sleeve and a balance, and the rear end of the middle machine body framework is provided with an interface for connecting with a rear machine body; the middle fuselage skin is coated on the middle fuselage skeleton; a large-size lapping plane lapped with the wing framework extends from the middle fuselage framework to two sides, and the length of the large-size lapping plane is one fourth of the extension length of the single-side wing;

the rear fuselage comprises a rear fuselage skeleton and a rear fuselage skin; the rear fuselage skin is coated on the rear fuselage skeleton.

Preferably, the wing skeleton structure is a rectangular frame structure.

Preferably, the front body, the middle body and the rear body are connected by straight openings.

The invention has the following beneficial effects: the invention ensures that the model has the mass and the rotational inertia as small as possible under the condition of a large number of levels, and ensures that the reference center of the airplane model is coincided with the actual mass center of the model. The method has important significance for reducing the damage of model vibration to mechanisms in the wind tunnel in the test process and improving the precision of wind tunnel test data.

Drawings

FIG. 1 is a schematic diagram of the overall structure of a large-size dynamic derivative test model structure;

FIG. 2 is a structural skeleton diagram of a large-size dynamic derivative test model;

FIG. 3 is a schematic cross-sectional view of the front fuselage;

FIG. 4 is a schematic cross-sectional view of the mid-fuselage skeleton;

FIG. 5 is a schematic cross-sectional view of a slide rail;

FIG. 6 is a schematic illustration of the front fuselage skeleton, mid fuselage skeleton interface;

fig. 7 is a schematic view of an under wing structure.

Figure 1-front fuselage; 2-a middle fuselage; 3-rear fuselage; 4-an airfoil; 5-a slide rail; 6-front fuselage skeleton; 7-carbon fiber reinforced beams; 8-a forward fuselage skin; 9-handpiece balancing weight; 10-middle fuselage skeleton; 11-a mid-fuselage skin; 12-taper sleeve and balance; 13-rear fuselage skeleton; 14-rear fuselage skin; 15-wing skeleton; 16-a wing lap joint skeleton; 17-wingtip of wing; 18-wing skin; 19-a slide rail carbon fiber rear section; 20-a slide rail metal front section connecting seat; 21-hair house; 22-a hair-house guide vane.

Detailed Description

In order that the objects, aspects and advantages of the invention will become more apparent, the invention will be described by way of example only, and with reference to the accompanying drawings. It is to be understood that this description is made only by way of example and not as a limitation on the scope of the invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

The connection mentioned in the invention is divided into fixed connection and detachable connection, the fixed connection is non-detachable connection and includes but is not limited to folding edge connection, rivet connection, bonding connection, welding connection and other conventional fixed connection modes, the detachable connection includes but is not limited to threaded connection, snap connection, pin connection, hinge connection and other conventional detachment modes, when the specific connection mode is not clearly limited, at least one connection mode can be found in the existing connection modes by default to realize the function, and the skilled person can select according to the needs. For example: the fixed connection selects welded connection, and the detachable connection selects hinged connection.

In the present invention, unless otherwise explicitly stated or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as being permanently connected, detachably connected, or integral; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Embodiment 1, the present embodiment is described with reference to fig. 1 to 7, and a large-size dynamic derivative test model structure of the present embodiment includes a fuselage, a wing 4, and a sliding rail 5; the fuselage comprises a front fuselage 1, a middle fuselage 2 and a rear fuselage 3; the length of the fuselage and the maximum extension length of the wings do not exceed 40% of the width of the wind tunnel test section; the front machine body 1, the middle machine body 2 and the rear machine body 3 are connected in sequence; the wings 4 are connected with the middle fuselage 2; the wings 4 are provided with slide rails 5; the connecting part of the slide rail and the wing is defined as a metal front-section connecting seat 20 of the slide rail and is made of metal materials, the metal front-section connecting seat 20 of the slide rail is of a hollow structure, and the rest part of the slide rail is defined as a carbon fiber rear section 19 of the slide rail and is made of carbon fiber materials;

the metal front section connecting seat 20 of the slide rail is bonded with the rear end of the slide rail into an integral structure, so that the slide rail is not disassembled and assembled any more, three slide rails are arranged on the wing, and each slide rail is connected with the wing framework 15 through a screw; is arranged on the side of the trailing edge of the wing.

The front fuselage 1 comprises a front fuselage skeleton 6, a carbon fiber reinforced beam 7, a front fuselage skin 8 and a nose balancing weight 9;

the rear end of the front fuselage framework 6 is provided with an interface for connecting with the middle fuselage 2; the front machine body framework 6 is provided with a carbon fiber reinforced beam 7; the front end of the front machine body 1 is provided with a machine head balancing weight 9; the front fuselage skin 8 is coated on the front fuselage skeleton 6;

the wing 4 comprises a wing framework 15, a wing lapping framework 16, a wing tip 17 and a wing skin 18; the wing lapping framework 16 is lapped with the wing framework 15; the wing framework 15 is connected with a wing tip 17; the wing skin 18 covers the wing 4;

a hair-sending chamber 21 is arranged below the wing 4, the appearance of the hair-sending chamber 21 is of a smooth annular structure, foam is used as a sandwich supporting material, carbon fiber skins are used as the appearance, the hair-sending chamber guide vanes 22 are bonded at corresponding interface positions on the hair-sending chamber 21, the hair-sending chamber guide vanes 22 are provided with sharp surfaces, and metal materials are used for machining.

The middle fuselage 2 comprises a middle fuselage framework 10, a middle fuselage skin 11, a taper sleeve and a balance 12; the front end of the middle machine body framework 10 is provided with a taper sleeve and a balance 12, and the rear end of the middle machine body framework 10 is provided with an interface for connecting with the rear machine body 3; the middle fuselage skin 11 is coated on the middle fuselage skeleton 10; a large-size lap joint plane lapped with the wing framework 15 extends from the middle fuselage framework 10 to two sides, and the length of the large-size lap joint plane is one fourth of the span length of the single-side wing;

the rear fuselage 3 comprises a rear fuselage skeleton 13 and a rear fuselage skin 14; the rear fuselage skin 14 is coated on the rear fuselage skeleton 13;

specifically, the hair-house 21 is arranged at the leading edge of the wing near the root and connected to the wing frame 15.

The number of the wings 4 is two, three sliding rails 5 and one engine room 21 are arranged on each wing 4 on each side;

specifically, the wing frame 15 is a rectangular frame structure.

Specifically, as shown in fig. 2, in order to reduce the overall weight of the model, a framework support is arranged inside the model. The model main body adopts a skin appearance and skeleton support mixed design form, and the skin and the skeleton are positioned by a mould and bonded and connected into a whole by resin;

specifically, as shown in fig. 3, the front body 1 is internally supported using a carbon fiber rib structure instead of a conventional metal skeleton. The front fuselage 1 is only connected with the middle fuselage skeleton 10 in a straight opening way, and the straight opening part is made of metal materials. Except for the middle fuselage framework 10, other parts connected with the front fuselage 1 do not exist, so that the main internal support adopts a carbon fiber rib structure, and the overall weight of the front fuselage 1 is reduced while skin is supported and the appearance is ensured;

specifically, as shown in fig. 4, a large-size lap joint plane with the wing frame 15 extends from the middle fuselage frame 10 to two sides, and the length of the plane is one fourth of the extension length of the single-sided wing 4. The lap joint surface of the wing framework 15 with large size can reduce the self-weight sagging phenomenon of the wing tip under the cantilever supporting state of the wing 4, simultaneously reduce the maximum stress at the stress concentration position possibly existing at the lap joint surface and improve the connection strength. Meanwhile, the weight reduction treatment of the middle area is carried out, so that the structural weight is reduced while the advantages are ensured;

specifically, as shown in fig. 5, the sliding rail 5 under the wing 4 is a non-main stressed component, and is designed by combining a carbon fiber material and a metal material. For example, at the connecting part of the sliding rail 5 and the wing 4 and the front edge sharp point, a metal material is required to meet the requirements of structure and appearance, and the interior of the metal structure can be hollowed to reduce weight. Other contoured portions may use a lower density carbon fiber material;

as shown in fig. 5, the hair chamber 21, which is also located below the wing 4, has a smooth ring-shaped structure, uses foam as a sandwich supporting material, uses a carbon fiber skin as the shape, has a small size of the deflector at the hair chamber 21 and has a sharp surface, uses a metal material for machining, and is bonded to a corresponding interface position on the hair chamber 21 after machining. The design of combining the carbon fiber material and the metal material is usually realized in the form of a "metal skeleton + carbon fiber skin". The appearance of the same part is divided into regions according to the appearance characteristics and the combination design form of two materials is adopted;

specifically, as shown in fig. 6, the three parts of the airplane model body are connected only by the frameworks, and the connection mode is straight connection.

The method is applied to the wind tunnel test of the dynamic derivative of the airplane. The invention effectively reduces the overall weight and the rotational inertia of the model, optimizes the process, meets the requirements of a processing technology and dynamic derivative test equipment, is applied to large-size dynamic derivative wind tunnel tests, and has stable operation and convenient assembly and disassembly.

Specifically, as shown in fig. 2, the wing frame 15 is mainly rectangular, and can better bear the load in the incoming flow direction. The wing root is in a form of combining a triangular frame and a rectangular frame, so that the strength of the root connection part can be improved. The overall strength of the wing 4 is improved, the maximum stress of the structure of the wing 4 is reduced, when the material of the wing framework 15 is widely selected and the maximum stress is small, the framework can be made of non-metal materials such as carbon fiber and the like, and the weight of the model can be effectively reduced.

The present embodiment is only illustrative and not intended to limit the scope of the patent, and those skilled in the art can make modifications to the part of the patent without departing from the spirit of the patent.

Claims

1. A large-size dynamic derivative test model structure is characterized in that: comprises a fuselage, wings (4) and sliding rails (5); the machine body comprises a front machine body (1), a middle machine body (2) and a rear machine body (3); the length of the fuselage and the maximum extension length of the wings do not exceed 40% of the width of the wind tunnel test section; the front machine body (1), the middle machine body (2) and the rear machine body (3) are connected in sequence; the wings (4) are connected with the middle fuselage (2); a sliding rail (5) is assembled on the wing (4); the connecting part of the slide rail and the wing is defined as a metal front-section connecting seat (20) of the slide rail and is made of metal materials, the metal front-section connecting seat (20) of the slide rail is of a hollow structure, and the rest part of the slide rail is defined as a carbon fiber rear section (19) of the slide rail and is made of carbon fiber materials;

the front fuselage (1) comprises a front fuselage skeleton (6), a carbon fiber reinforced beam (7), a front fuselage skin (8) and a nose balancing weight (9);

the rear end of the front machine body framework (6) is provided with an interface used for being connected with the middle machine body (2); a carbon fiber reinforced beam (7) is arranged on the front machine body framework (6); the front end of the front machine body (1) is provided with a machine head balancing weight (9); the front fuselage skin (8) is coated on the front fuselage skeleton (6);

the wing (4) comprises a wing framework (15), a wing lapping framework (16), a wing tip (17) and a wing skin (18); the wing lapping framework (16) is lapped with the wing framework (15); the wing framework (15) is connected with a wing tip (17) of the wing; the wing skin (18) is coated on the wing (4);

a hair-styling room (21) is arranged below the wing (4), the shape of the hair-styling room (21) is a smooth annular structure, foam is used as a sandwich supporting material, the shape of the hair-styling room is carbon fiber skin, a hair-styling flow deflector (22) is bonded at a corresponding interface position on the hair-styling room (21), the hair-styling flow deflector (22) is provided with a sharp surface, and the hair-styling flow deflector is manufactured by machining with a metal material;

the middle fuselage (2) comprises a middle fuselage skeleton (10), a middle fuselage skin (11), a taper sleeve and a balance (12); the front end of the middle machine body framework (10) is provided with a taper sleeve and a balance (12), and the rear end of the middle machine body framework (10) is provided with an interface for connecting the rear machine body (3); the middle fuselage skin (11) is coated on the middle fuselage skeleton (10); a large-size lapping plane lapped with the wing framework (15) extends from the middle fuselage framework (10) to two sides, and the length of the large-size lapping plane is one fourth of the extension length of the single-side wing;

the rear fuselage (3) comprises a rear fuselage skeleton (13) and a rear fuselage skin (14); the rear fuselage skin (14) is coated on the rear fuselage skeleton (13).

2. The large-scale dynamic derivative test model structure of claim 1, wherein: the wing framework (15) is of a rectangular frame structure.

3. The large-scale dynamic derivative test model structure of claim 1, wherein: the front machine body (1), the middle machine body (2) and the rear machine body (3) are connected through a straight port.