Aircraft controlled by combination of flexible wings and grid rudders

Abstract

The invention provides an aircraft controlled by combination of flexible wings and grid rudders. The aircraft comprises an aircraft body, the grid rudders and the flexible wings, the grid rudder is arranged at the tail end of the aircraft main body, and attitude control is performed on the aircraft through deflection of the grid rudder; the flexible wings are installed on the side wall of the aircraft body and located on the sides, away from the tail end of the aircraft body, of the grid rudders, and the flexible wings are unfolded and changed within the unfolding angle range. Through the installation of the flexible wings, the problems that the control capability of the grid rudder is insufficient in the transsonic speed stage and the pressure center coefficient is obviously changed are effectively solved, and the static stability of the aircraft is improved by controlling the change of the unfolding angle of the flexible wings. According to the aircraft, efficient and stable control can be achieved in the full-speed domain, compared with a traditional aircraft, the aircraft has the advantage of being lower in resistance during subsonic-speed and supersonic-speed flight, and good stability and high maneuverability are shown in the transonic-speed stage.

Description

Technical Field

[0001] The present application relates to the technical field of aircraft, and in particular to an aircraft controlled by a combination of flexible wings and grid rudders. Background Art

[0002] As a spatial multi-lift surface system consisting of an external frame and an internal grid layout, the grid rudder has a basic configuration of frame type and honeycomb type, among which the honeycomb type can be further divided into upright and oblique types. The grid rudder has many advantages that traditional flat wings do not have, such as excellent lift characteristics and less pressure center drift. With the continuous development of science and technology, the use of grid rudders as control surfaces in many aircraft models at home and abroad is increasing.

[0003] Aircraft with large aspect ratio are usually in a statically unstable state. A grid rudder is installed at the tail, and the force generated by it causes the center of pressure to move backward, making the aircraft statically stable.

[0004] The grid rudder has obvious problems in the transonic stage, which will cause airflow congestion. This phenomenon will cause its aerodynamic characteristics to deteriorate, the control efficiency to be greatly reduced, and then cause significant changes in the normal force coefficient and the pressure center coefficient, which will have a serious negative impact on the static stability of the aircraft. Summary of the invention

[0005] The purpose of the present application is to provide an aircraft controlled by a combination of flexible wings and grid rudders, which can achieve efficient and stable control in the full speed range. Compared with traditional aircraft, it has lower resistance when flying at subsonic and supersonic speeds, and exhibits good stability and strong maneuverability in the transonic stage.

[0006] To achieve the above-mentioned purpose, the present application provides an aircraft controlled by a combination of flexible wings and grid rudders, comprising an aircraft body, a grid rudder and a flexible wing; the grid rudder is arranged at the tail end of the aircraft body, and the attitude of the aircraft is controlled by the deflection of the grid rudder; the flexible wing is installed on the side wall of the aircraft body, and the flexible wing is located on the side of the grid rudder away from the tail end of the aircraft body, and the flexible wing is unfolded and changed within the unfolding angle range.

[0007] The aircraft controlled by a combination of flexible wings and grid rudders as described above, wherein the flexible wing includes an upper frame, a lower frame and an unfolding mechanism; the end of the upper frame and the end of the lower frame are rotatably connected; the unfolding mechanism is connected between the upper frame and the lower frame, and the unfolding mechanism drives the upper frame and the lower frame to unfold to a certain angle; the upper frame or the lower frame is parallel to the central axis of the aircraft body, and is fixedly connected to the side wall of the aircraft body.

[0008] The aircraft controlled by the combination of flexible wings and grid rudders as described above, wherein the unfolding mechanism includes a central driving rod, a first side rod and a second side rod; one end of the first side rod is connected to the upper frame, and the other end is rotatably connected to the second side rod; one end of the second side rod is connected to the lower frame, and the other end is rotatably connected to the first side rod; one end of the central driving rod is connected to the rotationally connected end of the upper frame and the lower frame; the other end is connected to the rotationally connected end of the first side rod and the second side rod; the central driving rod is extended or shortened to drive the first side rod to swing a certain angle relative to the upper frame and the second side rod to swing a certain angle relative to the lower frame, so as to change the angle between the upper frame and the lower frame.

[0009] The aircraft controlled by the combination of flexible wings and grid rudders as described above, wherein the upper frame has an upper limit slot, the end of the first side rod is limited in the upper limit slot and is rotatably connected in the upper limit slot; the lower frame has a lower limit slot, the end of the second side rod is limited in the lower limit slot and is rotatably connected in the lower limit slot.

[0010] As described above, the aircraft controlled by the combination of flexible wings and grid rudders, wherein the slenderness ratio γ of the aircraft body is solved according to the length and diameter of the aircraft body; wherein the slenderness ratio γ of the aircraft body = L / D; L represents the length of the aircraft body; D represents the diameter of the aircraft body; according to the slenderness ratio γ of the aircraft body, the grid rudder span R is calculated; if 10<γ<20, then R=0.5D; if 20<γ<30, then R=0.5*(1+2D / L)*D.

[0011] As described above, in the aircraft controlled by a combination of a flexible wing and a grid rudder, the chord length M of the flexible wing is calculated based on the slenderness ratio γ of the aircraft body and the span R of the grid rudder; if 10<γ<20, the chord length M of the flexible wing is R; if 20<γ<30, the chord length M of the flexible wing is R*(1+2D / L).

[0012] As described above, in the aircraft controlled by a combination of a flexible wing and a grid rudder, the distance S between the flexible wing and the grid rudder axis is calculated based on the slenderness ratio γ of the aircraft body and the lower chord length M of the flexible wing; if 10<γ<20, then the distance S=M between the flexible wing and the grid rudder axis; if 20<γ<30, then the distance S=M(1+D / L) between the flexible wing and the grid rudder axis.

[0013] The aircraft controlled by the combination of the flexible wing and the grid rudder as described above, wherein the deployment angle of the flexible wing is changed according to the flight situation of the aircraft.

[0014] As described above, the aircraft controlled by the combination of flexible wings and grid rudders, wherein the deployment angle range of the flexible wings is 0 to 45 degrees.

[0015] The aircraft controlled by a combination of flexible wings and grid rudders as described above, wherein at least two of the flexible wings are symmetrically arranged on the side of the aircraft body.

[0016] The beneficial effects achieved by this application are as follows:

[0017] (1) The aircraft of the present application has efficient and stable control in the full speed range. When flying at subsonic and supersonic speeds, the resistance of the aircraft is significantly lower than that of traditional aircraft. This advantage greatly improves the flight performance of the aircraft in these two speed ranges. In the transonic stage, the aircraft can maintain good stability, and its maneuverability is enhanced and the aerodynamic elastic force is reduced, which provides a strong guarantee for the operation of the aircraft in complex flight environments.

[0018] (2) The present application deploys the flexible wing within the range of 0-45° according to the flight conditions, thereby solving a series of problems caused by airflow congestion of the grid rudder in the transonic stage, including deterioration of aerodynamic characteristics, reduction of control efficiency and adverse effects on the static stability of the aircraft, thereby fundamentally improving the flight quality of the aircraft in the transonic stage. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For those skilled in the art, other drawings can also be obtained based on these drawings.

[0020] Figure 1 This is a schematic diagram of the structure of an aircraft controlled by a combination of flexible wings and grid rudders according to an embodiment of the present application.

[0021] Figure 2 This is a schematic diagram of an aircraft controlled by a combination of flexible wings and grid rudders in an embodiment of the present application with the flexible wings in a folded state.

[0022] Figure 3 Schematic diagram of the flexible wing deployment in the embodiment of the present application Figure 1 .

[0023] Figure 4 Schematic diagram of the flexible wing deployment in the embodiment of the present application Figure 2 .

[0024] Figure 5 Schematic diagram of the grid rudder and flexible wing design method of the aircraft in this application.

[0025] Figure numerals: 1-aircraft body; 2-grid rudder; 3-flexible wing; 31-upper frame; 32-lower frame; 33-central driving rod; 34-first side rod; 35-second side rod; 311-upper limit slot; 321-lower limit slot. DETAILED DESCRIPTION

[0026] The following is a clear and complete description of the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0027] like Figure 1 As shown, an aircraft controlled by a combination of a flexible wing and a grid rudder includes an aircraft body 1, a grid rudder 2 and a flexible wing 3; the grid rudder 2 is arranged at the tail end of the aircraft body, and the attitude of the aircraft is controlled by the deflection of the grid rudder 2; the flexible wing 3 is installed on the side wall of the aircraft body, and the flexible wing 3 is located on the side of the grid rudder 2 away from the tail end of the aircraft body, and the flexible wing 3 is unfolded and changed within the unfolding angle range. The installation of the flexible wing 3 effectively compensates for the insufficient control ability of the grid rudder 2 in the transonic stage and the problem of significant changes in the pressure center coefficient, and improves the static stability of the aircraft by controlling the change in the unfolding angle of the flexible wing 3.

[0028] As a specific embodiment of the present invention, the aircraft body 1 has a large slenderness ratio. Generally, an aircraft with a slenderness ratio greater than 10 can be considered to have a large slenderness ratio. The overall shape of the aircraft body 1 of the present application is a cylinder. In many cases, the center of pressure of an aircraft with a large slenderness ratio is in a statically unstable state before the center of mass. If there is a grid rudder 2 at the tail, the force generated by it causes the center of pressure to move backward, so that the aircraft is in a statically stable state. However, in the transonic stage, the grid rudder 2 causes the center of pressure to move forward due to flow congestion. Therefore, the flexible wing 3 needs to be unfolded to move the center of pressure of the aircraft body 1 backward, so that the aircraft continues to maintain a statically stable state, and at the same time, the unfolding angle of the flexible wing 3 is controlled to offset (or reduce) the unsteady aerodynamic force and aeroelasticity generated by the instability of the transonic flow.

[0029] As a specific embodiment of the present invention, the flexible wing 3 is in a folded state in the subsonic and supersonic flight states. In the folded state, the state diagram of the aircraft is as follows: Figure 2 As shown, when the flexible wing 3 is in a fully closed state, the flexible wing 3 can be retracted into the aircraft body 1 .

[0030] As a specific embodiment of the present invention, the flexible wing 3 is deployed in the transonic stage according to the flight conditions (the flight conditions include the angle of attack, Mach number, and sideslip angle), and the deployment angle range is 0-45 degrees. Figure 1As shown, it is a schematic diagram of the state of the aircraft when the flexible wing 3 is unfolded at an angle of 45 degrees.

[0031] like Figure 3 and 4 As shown, the flexible wing 3 includes an upper frame 31, a lower frame 32 and an unfolding mechanism; the end of the upper frame 31 and the end of the lower frame 32 are rotatably connected; the unfolding mechanism is connected between the upper frame 31 and the lower frame 32, and the unfolding mechanism is used to control the degree of unfolding and closing of the flexible wing 3. The unfolding mechanism drives the upper frame 31 and the lower frame 32 to unfold to a certain angle; the upper frame 31 or the lower frame 32 is parallel to the central axis of the aircraft body, and is fixedly connected to the side wall of the aircraft body.

[0032] like Figure 3 and 4 As shown, the unfolding mechanism includes a central driving rod 33, a first side rod 34 and a second side rod 35; one end of the first side rod 34 is connected to the upper frame 31, and the other end is rotatably connected to the second side rod 35; one end of the second side rod 35 is connected to the lower frame 32, and the other end is rotatably connected to the first side rod 34; one end of the central driving rod 33 is connected to the rotational connection end of the upper frame 31 and the lower frame 32; the other end is connected to the rotational connection end of the first side rod 34 and the second side rod 35; the central driving rod 33 is extended or shortened, driving the first side rod 34 to swing a certain angle relative to the upper frame 31 and the second side rod 35 to swing a certain angle relative to the lower frame 32, so as to change the angle between the upper frame 31 and the lower frame 32. The central driving rod 33 adopts an existing driving telescopic rod, which can be a pneumatic telescopic rod or a hydraulic power telescopic rod. The specific type of the central driving rod 33 is not limited here, as long as it can achieve telescopic.

[0033] like Figure 3 As shown, the upper frame 31 has an upper limit slot 311, and the end of the first side rod 34 is limited in the upper limit slot 311 and is rotatably connected in the upper limit slot 311; the lower frame 32 has a lower limit slot 312, and the end of the second side rod 35 is limited in the lower limit slot 312 and is rotatably connected in the lower limit slot 312.

[0034] like Figure 5 As shown, according to the length and diameter of the aircraft body 1, the slenderness ratio γ of the aircraft body 1 is solved; wherein, the slenderness ratio γ of the aircraft body 1 = L / D; L represents the length of the aircraft body 1; D represents the diameter of the aircraft body 1; according to the slenderness ratio γ of the aircraft body 1, the grid rudder span R is calculated; if 10<γ<20, then R=0.5D; if 20<γ<30, then R=0.5*(1+2D / L)*D. wherein, the grid rudder span r refers to the length of the grid rudder 2 when it is unfolded.

[0035] like Figure 5As shown, according to the slenderness ratio γ of the aircraft body 1 and the grid rudder span R, the lower chord length M of the flexible wing 3 is calculated; if 10<γ<20, the lower chord length M of the flexible wing 3 is R; if 20<γ<30, the lower chord length M of the flexible wing 3 is R*(1+2D / L). The lower chord length of the flexible wing 3 refers to the distance from the leading edge end point to the trailing edge end point along the lower edge of the flexible wing.

[0036] like Figure 5 As shown, according to the slenderness ratio γ of the aircraft body 1 and the lower chord length M of the flexible wing 3, the distance S between the flexible wing 3 and the grid rudder axis is calculated; if 10<γ<20, the distance S=M between the flexible wing 3 and the grid rudder axis; if 20<γ<30, the distance S=M(1+D / L) between the flexible wing 3 and the grid rudder axis.

[0037] As a specific embodiment of the present invention, the size and position of the grid rudder and the flexible wing are set according to the calculated grid rudder span R, the lower chord length of the flexible wing 3, and the distance S between the flexible wing 3 and the grid rudder axis.

[0038] As a specific embodiment of the present invention, the deployment angle of the flexible wing 3 is changed according to the flight conditions (angle of attack, Mach number, side slip angle) of the aircraft.

[0039] As a preferred embodiment of the present invention, the deployment angle range of the flexible wing 3 is 0 to 45 degrees. Here, the deployment angle range of the flexible wing 3 is not limited, and 0 to 45 degrees is only a preferred deployment angle range.

[0040] The flexible wing 3 of the present application is within a specific distance range in front of the rudder axis of the grid rudder 2. Within this range, the turbulence generated by the flexible wing 3 will not affect the aerodynamic characteristics of the grid rudder 2. This design provides an effective solution to the transonic stage problem of the grid rudder 2. The flexible wing 3 is deployed within the range of 0-45° according to the flight conditions (angle of attack, Mach number, sideslip angle).

[0041] As a specific embodiment of the present invention, at least two flexible wings 3 are symmetrically arranged on the side of the aircraft body 1. As a preferred embodiment of the present invention, two flexible wings 3 are symmetrically arranged on the side of the aircraft body 1, and the two flexible wings 3 improve the static stability of the aircraft in the transonic stage by controlling their deployment angles.

[0042] The main body of the aircraft of the present application is relatively slender, with the center of pressure located forward. It will move forward significantly in the transonic stage, causing the aircraft to become statically unstable. The flexible wing 3 is used to stabilize the center of pressure, so that the aircraft is in a statically stable state. The grid rudder 2 at its tail end is used for attitude control. This layout lays the foundation for the flight attitude adjustment of the aircraft.

[0043] The beneficial effects achieved by this application are as follows:

[0044] (1) The aircraft of the present application has efficient and stable control in the full speed range. When flying at subsonic and supersonic speeds, the resistance of the aircraft is significantly lower than that of traditional aircraft. This advantage greatly improves the flight performance of the aircraft in these two speed ranges. In the transonic stage, the aircraft can maintain good stability, and its maneuverability is enhanced and the aerodynamic elastic force is reduced, which provides a strong guarantee for the operation of the aircraft in complex flight environments.

[0045] (2) The present application deploys the flexible wing within the range of 0-45° according to the flight conditions, thereby solving a series of problems caused by airflow congestion of the grid rudder in the transonic stage, including deterioration of aerodynamic characteristics, reduction of control efficiency and adverse effects on the static stability of the aircraft, thereby fundamentally improving the flight quality of the aircraft in the transonic stage.

[0046] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0047] In the description of the present application, the word "for example" is used to mean "used as an example, illustration or explanation". Any embodiment described as "for example" in the present application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is given to enable any technician in the field to implement and use the present invention. In the following description, details are listed for the purpose of explanation. It should be understood that a person of ordinary skill in the art can recognize that the present invention can be implemented without using these specific details. In other examples, well-known structures and processes will not be elaborated in detail to avoid obscuring the description of the present invention with unnecessary details. Therefore, the present invention is not intended to be limited to the embodiments shown, but is consistent with the widest scope consistent with the principles and features disclosed in the present application.

[0048] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims

1. An aircraft controlled by a combination of flexible wings and grid rudders, characterized in that: It includes an aircraft body, a grid rudder and a flexible wing; The grid rudder is arranged at the tail end of the aircraft body, and the attitude of the aircraft is controlled by the deflection of the grid rudder; The flexible wing is installed on the side wall of the aircraft body, and the flexible wing is located on a side of the grid rudder away from the tail end of the aircraft body, and the flexible wing is unfolded and changed within the unfolding angle range.

2. The aircraft controlled by a combination of flexible wings and grid rudders according to claim 1, characterized in that: The flexible wing comprises an upper frame, a lower frame and a deployment mechanism; The end of the upper frame is rotatably connected to the end of the lower frame; The upper frame and the lower frame are connected with the unfolding mechanism, and the unfolding mechanism drives the upper frame and the lower frame to unfold at a certain angle; The upper frame or the lower frame is parallel to the central axis of the aircraft body and is fixedly connected to the side wall of the aircraft body.

3. The aircraft controlled by a combination of flexible wings and grid rudders according to claim 2, characterized in that: The deployment mechanism includes a central drive rod, a first side rod and a second side rod; One end of the first side rod is connected to the upper frame, and the other end is rotatably connected to the second side rod; One end of the second side rod is connected to the lower frame, and the other end is rotatably connected to the first side rod; One end of the central driving rod is connected to the rotation connection ends of the upper frame and the lower frame; the other end is connected to the rotation connection ends of the first side rod and the second side rod; The central driving rod is extended or shortened to drive the first side rod to swing at a certain angle relative to the upper frame and the second side rod to swing at a certain angle relative to the lower frame, so as to change the angle between the upper frame and the lower frame.

4. The aircraft controlled by a combination of flexible wings and grid rudders according to claim 3, characterized in that: The upper frame has an upper limit slot, and the end of the first side rod is limited in the upper limit slot and rotatably connected in the upper limit slot; The lower frame has a lower limit slot, and the end of the second side rod is limited in the lower limit slot and rotatably connected in the lower limit slot.

5. The aircraft controlled by a combination of flexible wings and grid rudders according to claim 1, characterized in that: According to the length and diameter of the aircraft body, the slenderness ratio γ of the aircraft body is solved; Wherein, the slenderness ratio of the aircraft body γ=l / D; K represents the length of the aircraft body; D represents the diameter of the aircraft body; According to the slenderness ratio γ of the aircraft body, the grid rudder span R is calculated; If 10<γ<20, then R=0.5D; If 20<γ<30, then R=0.5*(1+2D / L)*D.

6. The aircraft controlled by a combination of flexible wings and grid rudders according to claim 5, characterized in that: According to the slenderness ratio γ of the aircraft body and the span R of the grid rudder, the lower chord length M of the flexible wing is calculated; If 10<γ<20, the lower chord length of the flexible wing M=R; If 20<γ<30, the lower chord length of the flexible wing M=R*(1+2D / L).

7. The aircraft controlled by a combination of flexible wings and grid rudders according to claim 6, characterized in that: According to the slenderness ratio γ of the aircraft body and the lower chord length M of the flexible wing, the distance S between the flexible wing and the grid rudder axis is calculated; If 10<γ<20, then the distance between the flexible wing and the grid rudder axis is S=M; If 20<γ<30, the distance between the flexible wing and the grid rudder axis is S=M(1+D / L).

8. The aircraft controlled by a combination of flexible wings and grid rudders according to claim 7, characterized in that: The unfolding angle of the flexible wing is changed according to the flight conditions of the aircraft.

9. The aircraft controlled by a combination of flexible wings and grid rudders according to claim 7, characterized in that: The unfolding angle of the flexible wing ranges from 0 to 45 degrees.

10. The aircraft controlled by a combination of flexible wings and grid rudders according to claim 9, characterized in that: At least two of the flexible wings are symmetrically arranged on the side of the aircraft body.

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