Modal conversion system and method for wide-speed-range bidirectional flying wing aircraft

Abstract

The invention discloses a wide-speed-range two-way flying wing aircraft mode conversion system and method, and the system comprises two foldable telescopic all-moving empennages (9) and a power system (10) which are arranged on an aircraft main body fuselage (11), and the number of the all-moving empennages (9) is two. The two all-moving empennages (9) are symmetrically arranged at the tail of the upper surface of an aircraft body (11) in the direction of the first axis of the aircraft, the first axis is perpendicular to the low-speed modal flight incoming flow direction of the aircraft and parallel to the high-speed modal flight incoming flow direction of the aircraft, and each all-moving empennage (9) comprises an outer wing section (1), an inner wing section (2) and a rotating shaft (3). The bottom of the inner wing section (2) is rotationally connected with an aircraft body through a rotating shaft (3), so that the outer wing section (1) and the inner wing section (2) are overturned and folded, the outer wing section (1) is connected to the top of the inner wing section (2), and the outer wing section (1) can be retracted into the inner wing section (2) and can also extend out of the inner wing section (2).

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft, and relates to a mode conversion system and method for a wide-speed-range bidirectional flying-wing aircraft. Background Art

[0002] In 2009, Professor Zha Gecheng and his research team proposed a new concept of supersonic bidirectional flying wing aircraft with low sonic boom and high aerodynamic efficiency. Its basic planar shape is approximately rhombus-shaped: in the subsonic state, the aircraft flies in a large aspect ratio attitude to ensure sufficient lift; in the supersonic state, the aircraft flies in a small aspect ratio attitude to reduce shock wave drag; the conversion between high-speed and low-speed flight modes is achieved by rotating the aircraft 90°, such as Figure 1 As shown in the figure. Since the modal conversion process of the bidirectional flying wing aircraft is complicated, the modal conversion scheme for this layout is a technical difficulty in the research, including: power form, driving force and rudder control during the modal conversion process, and the connection method between the aircraft body and the power system.

[0003] The existing modal conversion solutions are:

[0004] like Figure 2-3 As shown in the figure, the first scheme uses air control surfaces to convert flight modes. A fully movable vertical tail with a large rotation range is configured near the tail of the aircraft in the two flight attitudes to provide yaw moment during the high-speed and low-speed mode conversion process. At the same time, this scheme places two independent engines on the relative vertical axis of the aircraft. The low-speed engine uses a high-performance turbine engine, and the high-speed engine uses a rocket engine.

[0005] like Figure 4 As shown, Scheme 2 utilizes the aerodynamic force provided by the deflection of the control surface (i.e., the aileron of the aircraft in the figure) to generate a yaw moment to deflect the fuselage 90° to achieve modal conversion. The engine is a twin-engine turbojet engine, which is connected to the fuselage through a circular platform in the center of the aircraft. At the same time, a built-in electromagnetic system controls the engine disc to ensure that the direction of the engine is consistent with the flight direction during the modal conversion process.

[0006] The main disadvantages of the existing bidirectional flying wing aerodynamic layout aircraft mode conversion scheme are:

[0007] Solution 1: In order to provide the yaw moment required for mode conversion, an asymmetric tail is added to the clean flying wing layout aerodynamic shape, which increases the drag and asymmetric aerodynamic force, which is not conducive to the control of the aircraft; two sets of mutually perpendicular power systems are used to provide thrust for the two modes, the structure is heavy, and the thrust direction of the two power systems is fixed and cannot be changed during the mode conversion process, so smooth power switching cannot be achieved.

[0008] Option 2: Flying wing aircraft have the problem of low control efficiency of the control surfaces. Using the aircraft's own ailerons to provide the yaw torque required for mode conversion may result in insufficient torque, resulting in a slow mode conversion speed. The aircraft is in an asymmetric aerodynamic state for a long time, which is not conducive to control. The power system uses a turbojet engine with a narrow operating Mach number range. The engine direction is controlled by an electromagnetic system, the control torque may be insufficient and the control system requirements are high. Summary of the invention

[0009] The object of the present invention is to provide a wide speed range bidirectional flying wing aircraft mode conversion system and method, which utilizes a foldable retractable tail, a large turntable mechanism and a TBCC (turbine-based combined power cycle engine) to overcome the above-mentioned shortcomings and achieve fast and stable mode conversion.

[0010] The technical solution adopted by the present invention is:

[0011] A wide-speed range bidirectional flying wing aircraft mode conversion system comprises a foldable and retractable full-moving tail wing and a power system arranged on the main fuselage of the aircraft.

[0012] There are two fully movable tail wings, which are symmetrically arranged on the tail part of the upper surface of the aircraft main fuselage along the first axis of the aircraft. The first axis is perpendicular to the flow direction of the aircraft's low-speed mode flight and parallel to the flow direction of the aircraft's high-speed mode flight. The fully movable tail wing includes an outer wing section, an inner wing section, and a rotating shaft. The bottom of the inner wing section is rotatably connected to the aircraft's main fuselage through the rotating shaft to achieve flipping and folding of the outer wing section and the inner wing section. The outer wing section is connected to the top of the inner wing section, and the outer wing section can be retracted into the inner wing section or extended from the inner wing section.

[0013] Furthermore, the inner wing section includes a fixed part and a deflection part, and the fixed part is rotatably connected to the main fuselage of the aircraft through a rotating shaft. The system also includes a folding locking pin, a telescopic locking pin and a full-moving tail shaft. The full-moving tail shaft sequentially connects the fixed part, the deflection part and the outer wing section from bottom to top, and the deflection part and the outer wing section can rotate around the full-moving tail shaft. The folding locking pin can be inserted into the lower end of the full-moving tail shaft to achieve flipping limitation of the outer wing section and the inner wing section. The full-moving tail shaft includes a thicker section located in the inner wing section and a thinner section located in the outer wing section, the thicker section is hollow, and the thinner section can be accommodated in the thicker section. The telescopic locking pin is used to insert into the full-moving tail shaft to achieve limitation when the inner wing section extends a set length.

[0014] Furthermore, it also includes a telescopic slider and a telescopic slideway matched with the telescopic slider, and the telescopic slider is located in the outer wing section.

[0015] Furthermore, it also includes a large turntable mechanism, which is located in the middle of the lower surface of the aircraft main body fuselage. The large turntable mechanism can rotate relative to the aircraft main body fuselage, and the power system is arranged on the large turntable mechanism.

[0016] Furthermore, the large turntable mechanism is provided with an oil tank, a control system, and a mission load.

[0017] Furthermore, the power system is a turbine-based combined power cycle engine.

[0018] Furthermore, ailerons are also arranged on the main fuselage of the aircraft.

[0019] According to the conversion method of the wide-speed range two-way flying wing aircraft modal conversion system, in the initial state, the full-moving tail is stored in the upper surface of the aircraft main fuselage, the two-way flying wing aircraft takes off from the low-speed mode, accelerates to the high subsonic range, and the aircraft begins to convert from the low-speed mode to the high-speed mode. The full-moving tail is unfolded around the rotation axis, the locking pin locks the full-moving tail shape, the outer wing section extends from the inner wing section to provide the torque required for the aircraft to rotate, the full-moving tail and the aircraft main fuselage and the large turntable mechanism rotate relative to each other, and when the aircraft main fuselage rotates °, the position of the aircraft main fuselage and the large turntable mechanism is locked so that they cannot rotate relative to each other, completing the modal conversion and converting to the high-speed mode. The aircraft continues to climb and accelerates to hypersonic speed. After completing the high-speed flight mission, the two-way flying wing aircraft decelerates to the high subsonic range and begins to transform from the high-speed mode to the low-speed mode. The full-moving tail wing deflects to provide the torque required for the rotation of the aircraft. The full-moving tail wing and the main fuselage of the aircraft and the large turntable mechanism rotate relative to each other. When the main fuselage of the aircraft rotates, the positions of the main fuselage of the aircraft and the large turntable mechanism are locked. The full-moving tail wing is folded and attached to the upper surface of the main fuselage of the aircraft, completing the mode conversion, changing to the low-speed mode, and completing the subsequent flight mission. During the mode conversion process, the deflected part of the inner wing section and the outer wing section rotate around the full-moving tail wing rotation axis when the aircraft needs to adjust the yaw moment.

[0020] The beneficial effects of the present invention are:

[0021] (1) The system of the present invention has no additional mechanism and no additional requirements for the control system of the bidirectional flying wing aircraft;

[0022] (2) The retractable and foldable "V"-shaped full-moving tail wing not only provides rotational torque during the mode conversion process, but also enhances the control capability of the aircraft in the high-speed mode. It has multiple uses and does not increase the additional resistance in the low-speed mode. (3) The large turntable can balance the weight and volume of the two relatively rotating parts (power system and wing-body assembly), which is beneficial to improving the stability of the mode conversion process. (4) TBCC (turbine-based combined power cycle engine) combines turbojet engine and ramjet engine with a wide operating speed range.

[0023] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a conceptual diagram of a double-wing flying wing layout aircraft.

[0025] Figure 2 It is a structural diagram of an existing bidirectional flying wing modal conversion scheme.

[0026] Figure 3 It is a structural diagram of an existing bidirectional flying wing modal conversion scheme.

[0027] Figure 4 Figure 2 is a second diagram of an existing bidirectional flying wing modal conversion scheme.

[0028] Figure 5 This is an expanded view of the fully movable tail of the bidirectional flying wing aircraft mode conversion system of the present invention.

[0029] Figure 6 This is a diagram of the fully movable tail wing of the bidirectional flying wing aircraft mode conversion system of the present invention being folded.

[0030] Figure 7 This is a position diagram of the large turntable of the bidirectional flying wing aircraft mode conversion system of the present invention.

[0031] Figure 8 It is a schematic diagram of the mode conversion process of the mode conversion system of the bidirectional flying wing aircraft of the present invention.

[0032] Fig. 9 It is a schematic diagram of the interior of the bidirectional flying wing aircraft of the present invention.

[0033] Fig.10 It is a schematic diagram of the large turntable component of the present invention.

[0034] Fig.11 Schematic diagram of the foldable and retractable tail wing components.

[0035] Fig.12 Schematic diagram of the unfolding process of the foldable and retractable tail wing.

[0036] Fig.13 Schematic diagram of the process of extending the outer wing section of the foldable and retractable tail.

[0037] Fig.14 Schematic diagram of the deflection of the foldable and retractable tail wing. DETAILED DESCRIPTION

[0038] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] like Figure 5-7 The figure shows a schematic diagram of a modal conversion system of a bidirectional flying wing aircraft of the present invention: 11 is the main fuselage of the aircraft; 9 is a "V"-shaped foldable and retractable full-movable tail, which is divided into two parts: an inner wing section and an outer wing section; 13 is an aileron (control surface) of the aircraft, which realizes pitch, yaw, roll and other controls; 10 is a power system of the aircraft, which uses a TBCC (turbine-based combined power cycle engine) to achieve flight in a wide speed range of 0 to 5 Ma; 12 is a large turntable mechanism connecting the fuselage and the engine, and the internal mechanical system can control the entire modal conversion process to ensure its stability.

[0040] like Figure 8 It is a schematic diagram of the mode conversion process. The leftmost side is the low-speed mode of the two-way flying wing, which is a clean flying wing layout configuration, without additional mechanisms, and has higher low-speed aerodynamic performance; the middle is the transition stage of the mode conversion, the full-moving tail 9 is opened, and a yaw moment that deflects the fuselage is generated, and at the same time, the aileron 13 of the aircraft is cooperated to achieve stable control of the aircraft; the rightmost side is the high-speed mode of the two-way flying wing, and the whole fuselage can achieve a 90° rotation. At the same time, the control efficiency of the aileron 13 of the aircraft decreases at high speed, and the unfolded "V"-shaped full-moving tail 9 can supplement the control ability of the aircraft.

[0041] like Fig. 9 The middle circular part is a large turntable mechanism 12 connecting the fuselage and the engine. In addition to adapting to the size of the TBCC engine, the mechanism has a large enough internal space to arrange fuel tanks, control systems, mission payloads, etc., transfer the weight of the main fuselage, reduce the moment of inertia, reduce the driving torque required for the rotation of the full-moving tail 9, and enhance the stability of the modal conversion process.

[0042] Fig.10 The diagram is a schematic diagram of the components of the large turntable mechanism 12. In the diagram, the annular support slide connects the fuselage and the large turntable 12, providing support for the turntable and the embedded slide improves the stability of the rotation. The control motor is fixedly connected to the large turntable below and cooperates with the control gear to realize the control of the rotation angular velocity and angular acceleration during the modal conversion process, thereby improving the reliability of the modal conversion.

[0043] Fig.11Schematic diagram of the components of a foldable and retractable full-moving tail (after unfolding): 1 is the outer wing section, which can be retracted into the inner wing section 2 in the low-speed mode, adopts a beam structure, and is supported internally by wing beams and wing ribs; 2 is the inner wing section, which adopts a structure similar to a single-piece wing because of the space reserved internally to accommodate the outer wing, and is supported by a thickened skin and reinforced girders that fit the skin; 3 is the rotation axis when the tail is folded; 4 is the folding locking pin, which is inserted into the lower end of 7 (full-moving tail shaft) when the tail is unfolded to the set position to lock the unfolding angle; 5 is the telescopic locking pin, which locks the position after the outer wing section 1 is extended to a set length; 6 is the telescopic slider, and 8 is the telescopic slide; 7 is the full-moving tail shaft, the outer wing section shaft is thinner, and the inner wing section shaft is hollow, and the outer wing section shaft is inserted into the cavity when the tail is folded.

[0044] The inner wing section 2 includes a fixed part and a deflection part, and the fixed part is rotatably connected to the main fuselage of the aircraft through a rotating shaft 3. The full-movable tail shaft 7 connects the fixed part, the deflection part and the outer wing section 1 in sequence from bottom to top, and the deflection part and the outer wing section 1 can rotate around the full-movable tail shaft 7. The folding locking pin 4 can be inserted into the lower end of the full-movable tail shaft 7 to achieve the flipping limit of the outer wing section 1 and the inner wing section 2. The full-movable tail shaft 7 includes a thicker section located in the inner wing section 2 and a thinner section located in the outer wing section 1. The thicker section is hollow, and the thinner section can be accommodated in the thicker section. The telescopic locking pin 5 is used to insert the full-movable tail shaft 7 to achieve limit when the inner wing section 2 extends a set length.

[0045] Fig.12 The schematic diagram of the tail wing deployment process is as follows. Before the aircraft mode conversion, the foldable and retractable tail wing is close to the fuselage surface (such as Fig.12 (a in the figure), the outer wing section is accommodated in the inner wing section; during the mode conversion, the inner wing section of the tail rotates around the folding axis ( Fig.11 The middle rotating shaft 3) is unfolded to the set position (such as Fig.12 After that, the outer wing section pops out from the inner wing section (as shown in Figure bc in Figure 2). Fig.12 d in Figure ).

[0046] Fig.13 This is a schematic diagram of the process of the outer wing section of the tail wing popping out, from left to right: the outer wing section is completely retracted into the inner wing section, the outer wing section is popped outward using the slider and the slide, and the outer wing section is completely popped out and locked in place.

[0047] Fig.14 is a schematic diagram of the deflection of the full-movable tail wing 9, around Fig.11 The full-moving tail shaft 7 rotates. The deflection of the full-moving tail 9 is used to provide the yaw moment of the aircraft. When the aircraft makes a turning movement or controls the flight stability, the full-moving tail needs to be deflected. Adjusting the deflection angle can control the size of the yaw moment.

[0048] The two-way flying wing aircraft is composed of a low-speed mode (such as Figure 8 Left 1) Take off, accelerate to the high subsonic range, and the aircraft begins to change from low speed mode to high speed mode (such as Figure 8 Right 1) conversion, the motor drives the folding and retractable tail 9 to unfold, the locking pin 4 locks the tail 9 shape, provides the torque required for the rotation of the fuselage 11, and the fuselage 11 and the large turntable 12 rotate relative to each other. At the same time, the mechanical control system (motor, gear mechanism) inside the large turntable 12 starts to work, and adjusts the rotation speed and other aspects of the mode conversion process. When the fuselage 11 rotates 90° (such as Figure 8 Right 1), the mechanical control system locks the fuselage 11 and the large turntable, preventing relative rotation, completing the mode conversion and changing to the high-speed mode. The aircraft continues to climb and accelerate to hypersonic speed. The TBCC engine uses a turbojet engine at 0-3Ma and a ramjet engine at 3-5Ma. After completing the high-speed flight mission, the two-way flying wing aircraft decelerates to the high subsonic range and begins to convert from the high-speed mode to the low-speed mode. The mechanical control system is unlocked, and the full-moving tail 9 is deflected to provide the torque required for the rotation of the fuselage 11. The fuselage 11 and the turntable 12 rotate relative to each other, and the control system ensures the stability of the mode conversion. When the fuselage 11 rotates 90°, the mechanical control system is locked again, and the folding and retractable tail 9 is driven by the motor to be retracted and attached to the surface of the aircraft, completing the mode conversion, changing to the low-speed mode, and completing the subsequent flight mission.

[0049] TBCC (turbine-based combined power cycle engine) can be replaced by other power forms, such as RBCC (rocket-based combined power cycle engine), RTBCC (rocket and turbine-based combined power cycle engine), etc.

[0050] The above description is only a preferred 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 replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wide speed range bidirectional flying wing aircraft mode conversion system, It is characterized in that It comprises a foldable and retractable full-movable tail wing (9) and a power system (10) arranged on the main fuselage (11) of the aircraft. The number of the fully movable tail wings (9) is two. The two fully movable tail wings (9) are symmetrically arranged at the tail of the upper surface of the aircraft main fuselage (11) along the first axis of the aircraft. The first axis is perpendicular to the direction of the aircraft low-speed mode flight flow and parallel to the direction of the aircraft high-speed mode flight flow. The fully movable tail wing (9) comprises an outer wing section (1), an inner wing section (2), and a rotation axis (3). The bottom of the inner wing section (2) is rotationally connected to the aircraft main fuselage through the rotation axis (3) so as to realize the flipping and folding of the outer wing section (1) and the inner wing section (2). The outer wing section (1) is connected to the top of the inner wing section (2). The outer wing section (1) can be retracted into the inner wing section (2) and can also be extended from the inner wing section (2).

2. The wide speed range bidirectional flying wing aircraft mode conversion system according to claim 1, It is characterized in that The inner wing section (2) comprises a fixed part and a deflection part, wherein the fixed part is rotatably connected to the main fuselage of the aircraft through a rotation shaft (3). The system further comprises a folding locking pin (4), a telescopic locking pin (5) and a fully movable tail wing rotating shaft (7). The fully movable tail wing rotating shaft (7) sequentially connects the fixed part, the deflection part and the outer wing section (1) from bottom to top, wherein the deflection part and the outer wing section (1) can rotate around the fully movable tail wing rotating shaft (7). The folding locking pin (4) can be inserted into the lower end of the fully movable tail wing rotating shaft (7) to achieve the flipping limit of the outer wing section (1) and the inner wing section (2). The fully movable tail wing rotating shaft (7) comprises a thicker section located in the inner wing section (2) and a thinner section located in the outer wing section (1), wherein the thicker section is hollow and the thinner section can be accommodated in the thicker section. The telescopic locking pin (5) is used to insert the fully movable tail wing rotating shaft (7) to achieve the limit when the inner wing section (2) extends to a set length.

3. The wide speed range bidirectional flying wing aircraft mode conversion system according to claim 2, It is characterized in that It also includes a telescopic slider (6) and a telescopic slideway (8) that cooperates with the telescopic slider (6), and the telescopic slider (6) is located in the outer wing section (1).

4. The wide speed range bidirectional flying wing aircraft mode conversion system according to claim 2 or 3, It is characterized in that It also includes a large turntable mechanism (12), which is located in the middle of the lower surface of the aircraft main body (11), and the large turntable mechanism (12) can rotate relative to the aircraft main body (11), and the power system (10) is arranged on the large turntable mechanism (12).

5. The wide speed range bidirectional flying wing aircraft mode conversion system according to claim 4, It is characterized in that The large turntable mechanism (12) is provided with an oil tank, a control system, and a mission load.

6. The wide speed range bidirectional flying wing aircraft mode conversion system according to claim 4, It is characterized in that The power system (10) is a turbine-based combined power cycle engine.

7. The wide speed range bidirectional flying wing aircraft mode conversion system according to claim 4, It is characterized in that Ailerons (13) are also arranged on the main fuselage (11) of the aircraft.

8. The conversion method of the wide speed range bidirectional flying wing aircraft mode conversion system according to any one of claims 2 to 7, It is characterized in that In the initial state, the fully movable tail wing (9) is stored in the upper surface of the aircraft main body (11), the two-way flying wing aircraft takes off from the low-speed mode, accelerates to the high subsonic range, and the aircraft begins to transform from the low-speed mode to the high-speed mode. The fully movable tail wing (9) is unfolded around the rotation axis (3), the locking pin (4) locks the shape of the fully movable tail wing (9), the outer wing section (1) extends from the inner wing section (2), and provides the torque required for the rotation of the aircraft. The fully movable tail wing (9) and the aircraft main body (11) and the large turntable mechanism (12) rotate relative to each other. When the aircraft main body (11) rotates 90 degrees, the positions of the aircraft main body (11) and the large turntable mechanism (12) are locked so that they cannot rotate relative to each other, and the mode conversion is completed and transformed into the high-speed mode. The aircraft continues to climb and accelerates. The invention relates to a method for controlling the yaw moment of the aircraft and the yaw moment of the aircraft. The method comprises: controlling the yaw moment of the aircraft and the yaw moment of the aircraft. The yaw moment of the aircraft and the yaw moment of the aircraft are controlled by ...

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