A power system for a short takeoff and vertical landing aircraft and its control method

Abstract

This application belongs to the technical field of the design of the power system for short takeoff and vertical landing aircraft, and specifically relates to a power system for short takeoff and vertical landing aircraft and its control method. By combining electric drive and mechanical drive, it replaces the pure mechanical drive form of a mechanical shaft-driven lift fan, which can reduce the complexity, weight, and design difficulty of the power system, shorten the length of the transmission shaft, and design to use liquid hydrogen to cool the superconducting motor. Moreover, it uses hydrogen combustion to generate lift, which can reduce the demand for power extracted from the engine, reduce the impact on engine performance, reduce the design difficulty of the engine, and can reduce the power of the transmission shaft, reduce the design difficulty and failure rate of the transmission shaft.

Description

Technical Field

[0001] This application belongs to the technical field of the power system design of short takeoff and vertical landing aircraft, and specifically relates to a power system for a short takeoff and vertical landing aircraft and its control method. Background Art

[0002] The short takeoff and vertical landing aircraft combines the advantages of fixed-wing and rotary-wing aircraft. It can not only significantly reduce the requirements of the aircraft for takeoff and landing ground conditions, but also has high flight performance.

[0003] Currently, the power system of short takeoff and vertical landing aircraft uses the method of mechanically driving a fan to achieve the balance and control of lift and torque. It is necessary to design devices such as couplings and clutches, which have a complex structure, large weight, high design difficulty, and a long drive shaft is required to transmit the power of the engine to the lift fan. The drive shaft has a high transmission power and a large power density, with extremely high design difficulty and high failure rate. In addition, a large amount of power needs to be extracted from the engine, which affects the performance of the engine and increases the design difficulty of the engine.

[0004] In view of the existence of the above technical defects, this application is proposed. Summary of the Invention

[0005] The purpose of this application is to provide a power system for a short takeoff and vertical landing aircraft and its control method to overcome or mitigate at least one aspect of the known technical defects.

[0006] The technical solution of this application is as follows:

[0007] On the one hand, a power system for a short takeoff and vertical landing aircraft is provided, including an engine, an outer duct air intake pipe, a lift fan, a superconducting motor, a drive motor, and a liquid hydrogen storage tank;

[0008] The nozzle of the engine uses a three-bearing rotating nozzle;

[0009] There are two outer duct air intake pipes, the inlets are connected to both sides of the engine, communicating with the outer duct of the engine, and the outlets are sequentially connected to an outer duct air intake combustion chamber and a roll nozzle, and the nozzle of the roll nozzle is vertically downward;

[0010] The lift fan is located in front of the engine, and its outlet is sequentially connected to a lift fan combustion chamber and a box nozzle, and the nozzle of the box nozzle is vertically downward;

[0011] The superconducting motor has an electric mode and a power generation mode, is connected to the low-pressure shaft of the engine through the main engine drive shaft, is located in front of the engine, and has a cooling flow path thereon;

[0012] The drive motor is connected to the superconducting motor through a cable and is connected to the lift fan through a lift fan drive shaft;

[0013] The liquid hydrogen storage tank is connected to the inlet of the cooling flow channel through a pipeline, and the outlet of the cooling flow channel is connected to two outer bypass duct air intake combustion chambers and the lift fan combustion chamber through pipelines.

[0014] Optionally, in the above short takeoff and vertical landing aircraft power system, the connection positions of the inlets of the two outer bypass duct air intake pipes on the engine are at the compressor part of the engine.

[0015] Optionally, in the above short takeoff and vertical landing aircraft power system, the lift fan is located on the axis of the engine;

[0016] The superconducting motor is located on the axis of the engine.

[0017] Optionally, in the above short takeoff and vertical landing aircraft power system, the superconducting motor is connected to the power supply system of the aircraft and the power system through cables.

[0018] On the other hand, a control method for a short takeoff and vertical landing aircraft power system is provided, which is used to control the above short takeoff and vertical landing aircraft power system, including:

[0019] When starting the engine, set the superconducting motor in the electric mode and supply power to the superconducting motor, so that the superconducting motor drives the low-pressure shaft of the engine to rotate. After the rotational speed of the low-pressure shaft reaches the rotational speed required for engine starting, supply fuel and ignite the engine to achieve engine starting;

[0020] After the engine is started, set the superconducting motor in the power generation mode, so that the superconducting motor generates electricity driven by the low-pressure shaft of the engine, and the generated electric energy can be supplied for use by the power supply system of the aircraft and the power system, and supplied for use by the drive motor;

[0021] When the aircraft takes off and lands, control the nozzle of the engine three-bearing rotating nozzle to be vertically downward, and open the nozzle adjusting vanes of the two roll nozzles and the cassette nozzle, so that the nozzles of the two roll nozzles and the cassette nozzle are opened, and control the superconducting motor to supply power to the drive motor to drive the lift fan to work. At the same time, control the liquid hydrogen storage tank to introduce liquid hydrogen into the cooling flow channel through a pipeline. The liquid hydrogen absorbs the heat generated by the operation of the superconducting motor along the way to cool the superconducting motor. The liquid hydrogen absorbs heat and vaporizes into gaseous hydrogen, and flows into the two outer bypass duct air intake combustion chambers and the lift fan combustion chamber through pipelines for ignition and combustion;

[0022] When the aircraft is cruising, control the nozzle of the engine three-bearing rotating nozzle to be horizontally backward, close the nozzle adjusting vanes of the two roll nozzles and the cassette nozzle, so that the nozzles of the two roll nozzles and the cassette nozzle are closed, and control the superconducting motor to stop supplying power to the drive motor, shut down the drive lift fan, and control the liquid hydrogen storage tank to stop introducing liquid hydrogen into the cooling flow channel through a pipeline, and shut down the two outer bypass duct air intake combustion chambers and the lift fan combustion chamber.

[0023] The present application has at least the following beneficial technical effects:

[0024] Provided is a power system for a short takeoff and vertical landing aircraft and its control method. By combining electric drive and mechanical drive, the pure mechanical drive form of a mechanical shaft driving a lift fan is replaced, which can reduce the complexity, weight, and design difficulty of the power system, shorten the length of the transmission shaft, design to cool the superconducting motor with liquid hydrogen, and use hydrogen combustion to generate lift, which can reduce the demand for extracting power from the engine, reduce the impact on engine performance, reduce the design difficulty of the engine, and can reduce the power of the transmission shaft, reduce the design difficulty and failure rate of the transmission shaft. Description of the Drawings

[0025] Figure 1 is a schematic diagram of the power system for a short takeoff and vertical landing aircraft provided by an embodiment of the present application;

[0026] Figure 2 is a schematic diagram of the installation of the power system for a short takeoff and vertical landing aircraft on the aircraft provided by an embodiment of the present application;

[0027] Figure 3 is a schematic diagram of the control state of the power system for a short takeoff and vertical landing aircraft during takeoff and landing of the aircraft provided by an embodiment of the present application;

[0028] Figure 4 is a schematic diagram of the control state of the power system for a short takeoff and vertical landing aircraft during cruise of the aircraft provided by an embodiment of the present application;

[0029] Wherein:

[0030] 1 - engine; 2 - outer duct air intake pipe; 3 - lift fan; 4 - superconducting motor; 5 - drive motor; 6 - liquid hydrogen storage tank;

[0031] 21 - outer duct air intake combustion chamber; 22 - roll nozzle;

[0032] 31 - lift fan combustion chamber; 32 - cassette nozzle.

[0033] For better illustration of this embodiment, some contents of the drawings are omitted, enlarged or reduced, and are only for illustrative purposes and should not be construed as a limitation to the present application. Detailed Embodiments

[0034] To make the technical solutions and their advantages of this application clearer, the following will further describe the technical solutions of this application clearly and completely in conjunction with the accompanying drawings. It can be understood that the specific embodiments described herein are only partial embodiments of this application, which are only used to explain this application and not to limit this application. It should be noted that for the convenience of description, only the parts related to this application are shown in the drawings, and other related parts can refer to the general design.

[0035] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of this application should be the ordinary meanings understood by those of ordinary skill in the art to which this application belongs. The "including" used in the description of this application means that the concept appearing before this word covers the concepts listed after this word and their equivalents, without excluding other related concepts.

[0036] In addition, the words indicating directions used in the description of this application are only used to indicate the relative directions or positional relationships. When the absolute position of the object being described changes, its relative positional relationship may also change accordingly. It should also be noted that unless otherwise clearly specified and limited, the words such as "installation" and "connection" used in the description of this application should be understood in a broad sense. For example, the connection can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. Those skilled in the art can understand their specific meanings in this application according to the specific situation.

[0037] A power system for a short takeoff and vertical landing aircraft, as Figure 1 shown, includes an engine 1, an outer duct air intake pipe 2, a lift fan 3, a superconducting motor 4, a drive motor 5, and a liquid hydrogen storage tank 6.

[0038] The nozzle of the engine 1 adopts a three-bearing rotating nozzle.

[0039] There are two outer duct air intake pipes 2, the inlets are connected to both sides of the engine 1, communicating with the outer duct of the engine 1, and the outlets are successively connected with an outer duct air intake combustion chamber 21 and a roll nozzle 22, and the nozzle of the roll nozzle 22 is vertically downward.

[0040] The two outer duct air intake pipes 2 are symmetrically arranged on both sides of the engine 1, and the connection positions of the inlets on the engine 1 are at the compressor part of the engine 1.

[0041] The outlet of the lift fan 3 is successively connected with a lift fan combustion chamber 31 and a box nozzle 32, and the nozzle of the box nozzle 32 is vertically downward.

[0042] The lift fan 3 is located in front of the engine 1 and on the axis of the engine 1.

[0043] The superconducting motor 4 has an electric mode and a power generation mode. It is connected to the low-pressure shaft of the engine 1 through the main engine transmission shaft, is located in front of the engine 1, on the axis of the engine 1, and has a cooling flow channel thereon. The superconducting motor 4 is connected to the power supply system of the aircraft and the power system through cables.

[0044] The drive motor 5 is connected to the superconducting motor 4 through a cable and to the lift fan 3 through the lift fan transmission shaft.

[0045] The liquid hydrogen storage tank 6 is arranged outside the engine 1, can be fixed to the aircraft structure, is connected to the inlet of the cooling flow channel through a pipeline, and the outlet of the cooling flow channel is connected to the two outer bypass air combustion chambers 21 and the lift fan combustion chamber 31 through pipelines.

[0046] The power system of the short takeoff and vertical landing aircraft disclosed in the above embodiment is installed on the aircraft as Figure 2 shown. The whole is located below the fuselage. The engine 1 is located at the tail of the fuselage. The two outer bypass air pipes 2 and their outer bypass air combustion chambers 21 and the roll nozzles 22 are located below the wings. The lift fan 3 and its lift fan combustion chamber 31 and the cassette nozzles 32 are located at the front of the fuselage.

[0047] The power system of the short takeoff and vertical landing aircraft disclosed in the above embodiment can be controlled with reference to the following method.

[0048] When starting the engine 1, set the superconducting motor 4 in the electric mode and supply power to the superconducting motor 4 to drive the low-pressure shaft of the engine 1 to rotate by the superconducting motor. After the rotational speed of the low-pressure shaft reaches the rotational speed required for engine starting, supply fuel and ignite the engine 1 to achieve the starting of the engine 1.

[0049] After the engine is started, set the superconducting motor 4 in the power generation mode to make the superconducting motor 4 generate electricity driven by the low-pressure shaft of the engine 1, extract power from the engine 1 for power generation, and the generated electric energy can be supplied for use in the power supply system of the aircraft and the power system, and for use in the drive motor 5.

[0050] When the aircraft takes off and lands, control the nozzles of the three-bearing rotating nozzle of the engine 1 to be vertically downward, and open the nozzle adjusting vanes of the two roll nozzles 22 and the cassette nozzles 32 to open the nozzles of the two roll nozzles 22 and the cassette nozzles 32, and control the superconducting motor 4 to supply power to the drive motor 5 to drive the lift fan 3 to work, as Figure 3As shown, at this time, the exhaust gas of the engine 1 is ejected downward through the three-bearing rotating nozzle. The two outer bypass duct air intake pipes 2 eject the air intake from the outer bypass duct of the engine 1 downward through the outer bypass duct air intake combustion chamber 21 and the roll nozzle 22. The exhaust gas of the lift fan 3 is ejected downward through the lift fan combustion chamber 31 and the cassette nozzle 32. The three of them jointly generate lift to balance and control the lift and moment of the aircraft, enabling the aircraft to perform short takeoff and vertical landing.

[0051] When the aircraft takes off and lands, the superconducting motor 4 extracts power from the engine 1 for power generation and supplies it to the drive motor 5 for use to drive the lift fan 3 to work. The superconducting motor 4 needs to generate power at a relatively large power. For this purpose, the liquid hydrogen storage tank 6 can be controlled to introduce liquid hydrogen into the cooling flow path through a pipeline. The liquid hydrogen absorbs the heat generated by the operation of the superconducting motor 4 along the way to cool the superconducting motor 4 to maintain the low-temperature environment required for the superconductivity of the superconducting motor 4, enabling the superconducting motor 4 to maintain power generation at a relatively large power. At the same time, the liquid hydrogen absorbs heat and gasifies into gaseous hydrogen, which flows into the two outer bypass duct air intake combustion chambers 21 and the lift fan combustion chamber 31 through the pipeline for ignition and combustion, and then is ejected downward through the two roll nozzles 22 and the cassette nozzle 32. In this way, the air intake of the two outer bypass duct air intake pipes 2 and the exhaust gas of the lift fan 3 can generate greater lift, facilitating the balance and control of the lift and moment of the aircraft, and enabling the full utilization of hydrogen.

[0052] When the aircraft is cruising, control the nozzle of the three-bearing rotating nozzle of the engine 1 to be horizontally backward, close the nozzle adjusting vanes of the two roll nozzles 22 and the cassette nozzle 32 to close the nozzles of the two roll nozzles 22 and the cassette nozzle 32, and control the superconducting motor 4 to stop supplying power to the drive motor 5, shut down the drive lift fan 3, and control the liquid hydrogen storage tank 6 to stop introducing liquid hydrogen into the cooling flow path through the pipeline, and shut down the two outer bypass duct air intake combustion chambers 21 and the lift fan combustion chamber 31, as Figure 4 shown. At this time, the two outer bypass duct air intake pipes 2 no longer intake air from the outer bypass duct of the engine 1, the lift fan 3 stops exhausting, and only the exhaust gas of the engine 1 is ejected backward through the three-bearing rotating nozzle to generate the thrust required for the aircraft to cruise. The superconducting motor 4 extracts power from the engine 1 for power generation, and only needs to supply the power supply system of the aircraft and the power system for use, and can meet the needs by generating power at a relatively small power, and there is no need to cool with liquid hydrogen anymore.

[0053] The power system of the short takeoff and vertical landing aircraft and its control method disclosed in the above embodiments replace the pure mechanical drive form of the mechanical shaft driving the lift fan 3 with a combination of electric drive and mechanical drive, which can reduce the complexity, weight and design difficulty of the power system, shorten the length of the transmission shaft, and design to use liquid hydrogen to cool the superconducting motor 4, and use hydrogen combustion to generate lift, which can reduce the demand for extracting power from the engine 1, reduce the impact on the performance of the engine 1, reduce the design difficulty of the engine 1, and can reduce the power of the transmission shaft, reduce the design difficulty and failure rate of the transmission shaft.

[0054] So far, the technical solutions of the present application have been described in conjunction with the preferred embodiments shown in the drawings. Those skilled in the art should understand that the protection scope of the present application is obviously not limited to these specific embodiments. Without departing from the principle of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present application.

Claims

1. A short take-off and vertical landing aircraft power system, characterized in that: It comprises an engine (1), an external duct air duct (2), a lift fan (3), a superconducting motor (4), a drive motor (5), and a liquid hydrogen storage tank (6); The nozzle of the engine (1) adopts a three-bearing rotating nozzle; There are two duct bleed air pipes (2), the inlets of which are connected to both sides of the engine (1) and communicate with the duct of the engine (1), and the outlets of which are connected to the duct bleed air combustion chamber (21) and the tumble nozzle (22) in sequence, and the nozzle of the tumble nozzle (22) is vertically downward; The lift fan (3) is located in front of the engine (1), and its outlet is connected to the lift fan combustion chamber (31) and the box nozzle (32) in sequence, and the nozzle of the box nozzle (32) is vertically downward; The superconducting motor (4) has an electric mode and a power generation mode, is connected to the low-pressure shaft of the engine (1) through the main engine transmission shaft, is located in front of the engine (1), and has a cooling flow channel thereon; The drive motor (5) is connected to the superconducting motor (4) via a cable, and is connected to the lift fan (3) via a lift fan drive shaft; The liquid hydrogen storage tank (6) is connected to the inlet of the cooling flow channel through a pipeline, and the outlet of the cooling flow channel is connected to the two external duct bleed air combustion chambers (21) and the lift fan combustion chamber (31) through a pipeline; When the aircraft takes off or lands, the nozzle of the three-bearing rotating nozzle of the engine (1) can be controlled to be vertically downward, and the nozzle adjustment plates of the two tumbling nozzles (22) and the box nozzle (32) can be opened to open the nozzles of the two tumbling nozzles (22) and the box nozzle (32), and the superconducting motor (4) can be controlled to supply power to the driving motor (5) so that the driving motor (5) drives the lift fan (3) to work. At the same time, the liquid hydrogen storage tank (6) is controlled to pass liquid hydrogen into the cooling flow channel through the pipeline. The liquid hydrogen absorbs heat generated by the operation of the superconducting motor (4) along the way to cool the superconducting motor (4). The liquid hydrogen absorbs heat and is gasified into gaseous hydrogen, which flows into the two outer duct bleed air combustion chambers (21) and the lift fan combustion chamber (31) through the pipeline for ignition and combustion. The superconducting motor (4) is connected to the power supply system of the aircraft and the power system through cables.

2. The short take-off and vertical landing aircraft power system according to claim 1, characterized in that: The connection position of the inlet of the two external duct air ducts (2) on the engine (1) is located at the compressor part of the engine (1).

3. The short take-off and vertical landing aircraft power system according to claim 2, characterized in that: The lift fan (3) is located on the axis of the engine (1); The superconducting motor (4) is located on the axis of the engine (1).

4. A method for controlling a short take-off and vertical landing aircraft power system, for controlling the short take-off and vertical landing aircraft power system according to claim 3, characterized in that: include: When starting the engine (1), the superconducting motor (4) is set in an electric mode and power is supplied to the superconducting motor (4), so that the superconducting motor drives the low-pressure shaft of the engine (1) to rotate. After the rotation speed of the low-pressure shaft reaches the rotation speed required for starting the engine, the engine (1) is fueled and ignited to start the engine (1); After the engine is started, the superconducting motor (4) is set in a power generation mode, so that the superconducting motor (4) generates electricity under the drive of the low-pressure shaft of the engine (1), and the generated electric energy can be supplied to the power supply system of the aircraft and the power system for use, and to the drive motor (5) for use; When the aircraft takes off or lands, the nozzle of the three-bearing rotating nozzle of the engine (1) is controlled to be vertically downward, and the nozzle adjustment plates of the two tumbling nozzles (22) and the box nozzle (32) are opened so that the nozzles of the two tumbling nozzles (22) and the box nozzle (32) are open, and the superconducting motor (4) is controlled to supply power to the driving motor (5) so that the driving motor (5) drives the lift fan (3) to work. At the same time, the liquid hydrogen storage tank (6) is controlled to pass liquid hydrogen into the cooling flow channel through the pipeline. The liquid hydrogen absorbs heat generated by the operation of the superconducting motor (4) along the way to cool the superconducting motor (4). The liquid hydrogen absorbs heat and is gasified into gaseous hydrogen, which flows into the two outer duct bleed air combustion chambers (21) and the lift fan combustion chamber (31) through the pipeline for ignition and combustion; When the aircraft is cruising, the nozzle of the three-bearing rotating nozzle of the engine (1) is controlled to be horizontally backward, the nozzle adjustment plates of the two tumble nozzles (22) and the box nozzle (32) are closed, so that the nozzles of the two tumble nozzles (22) and the box nozzle (32) are closed, and the superconducting motor (4) is controlled to stop supplying power to the drive motor (5), the driving lift fan (3) is shut down, and the liquid hydrogen storage tank (6) is controlled to stop supplying liquid hydrogen to the cooling flow channel through the pipeline, and the two outer duct bleed air combustion chambers (21) and the lift fan combustion chamber (31) are shut down.

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