Engine and aircraft

Abstract

The embodiment of the present application provides an engine and an aircraft, which belongs to the field of engine technology. The engine includes: an intake system, a precooling system, a turbocharger system, a ramjet combustion system, an exhaust system and a liquid circulation system; the engine has a first working mode, a second working mode and a third working mode; in the first working mode, after the incoming air enters the turbocharger system for supercharging, it is burned into combustion gas in the turbocharger system and the ramjet combustion system respectively, and finally expands in the exhaust system to generate thrust; in the second working mode, after the incoming air is precooled by the precooling system, it enters the turbocharger system for supercharging, and is burned into combustion gas in the turbocharger system and the ramjet combustion system respectively, and finally expands in the exhaust system to generate thrust; in the third working mode, the incoming air is burned into combustion gas by the ramjet combustion system, and finally expands in the exhaust system to generate thrust. The engine starts at zero speed and overcomes the problem of "thrust trap".

Description

Technical Field

[0001] The present application belongs to the field of engine technology, and specifically relates to an engine and an aircraft. Background Art

[0002] With the development of science and technology, aerospace engines have gone through more than a hundred years of development and formed three major branches: aviation turbine engines, rocket engines, and ramjet engines. Due to the high technical maturity, these three types of engines are widely used in their respective fields, but it is difficult to use them across fields. Turbine engines are extremely inefficient when cruising at high Mach numbers; rocket engines have low specific impulse and high propellant consumption, making it difficult to run for a long time; ramjet engines cannot achieve zero-speed start. However, the further development of the aerospace industry requires that the power system must meet the requirements of continuous and efficient operation in a wide speed range (Mach number 0-6 and higher) and large airspace (0-30km and higher) and be reusable. Obviously, it is difficult for the above three types of engines to meet this requirement directly, and people naturally think of combining them appropriately, that is, a combined engine.

[0003] However, although the existing combined engines have their own characteristics, none of them can effectively solve the "thrust trap (Mach 2-4)" problem, and it is difficult to achieve continuous, efficient and repeatable operation at 0-6 Mach. Summary of the invention

[0004] The present application aims to provide an engine and an aircraft to solve the problem that existing combined engines cannot efficiently solve the "thrust trap" problem and it is difficult to achieve continuous, efficient and repeatable operation at 0-6 Mach.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] In a first aspect, the present application discloses an engine for an aircraft, the engine comprising: an air intake system, a precooling system, a turbocharging system, a ramjet combustion system, an exhaust system, and a liquid circulation system arranged in sequence;

[0007] The engine has at least a first duct and a second duct, the first duct is at least formed in the precooling system, and the second duct is at least formed in the ramjet combustion system and the turbocharger system; the liquid circulation system is respectively connected to the precooling system, the turbocharger system and the ramjet combustion system;

[0008] The engine has a first working mode, a second working mode and a third working mode;

[0009] Among them, in the first working mode, the precooling system is closed, and the incoming air enters the turbocharger system through the second duct for supercharging, and then burns into combustion gas in the turbocharger system and the ramjet combustion system respectively, and finally expands in the exhaust system to generate thrust; in the second working mode, the incoming air enters the precooling system through the first duct for precooling, and then enters the turbocharger system for supercharging, and then burns into combustion gas in the turbocharger system and the ramjet combustion system respectively, and finally expands in the exhaust system to generate thrust; in the third working mode, the incoming air directly enters the ramjet combustion system through the second duct to become combustion gas, and finally expands in the exhaust system to generate thrust.

[0010] Optionally, the operating mode of the engine corresponds to the flight speed of the aircraft; wherein,

[0011] When the speed of the aircraft is 0-2 Mach, the engine operates in the first working mode; when the speed of the aircraft is 2-4 Mach, the engine operates in the second working mode; when the speed of the aircraft is 4-6 Mach, the engine operates in the third working mode.

[0012] Optionally, the precooling system comprises: a precooling fan and a heat exchanger connected in sequence; wherein,

[0013] The pre-cooling fan is close to the outlet of the air intake system.

[0014] Optionally, the turbocharger system comprises an axial compressor, a main combustion chamber and a turbine connected in sequence; wherein,

[0015] The axial flow compressor is close to the outlet of the precooling system.

[0016] Optionally, the liquid circulation system comprises: a liquid tank, a starting liquid pump, a hydraulic turbine, a low-pressure liquid pump and a high-pressure liquid pump; wherein,

[0017] The liquid tank is connected to one end of the heat exchanger through the starting liquid pump, the other end of the heat exchanger is connected to the high-pressure liquid pump through the low-pressure liquid pump, and the hydraulic turbine is connected between the high-pressure liquid pump and the liquid tank;

[0018] The precooling fan is connected to the low-pressure liquid pump via a driving shaft to drive the low-pressure liquid pump;

[0019] The turbine is connected to the high-pressure liquid pump via a driving shaft to drive the high-pressure liquid pump;

[0020] The hydraulic turbine is connected to the axial flow compressor via a driving shaft to drive the axial flow compressor.

[0021] Optionally, the heat exchanger is a liquid-cooled heat exchanger.

[0022] Optionally, the engine further comprises: a first switch disposed in the first duct, a second switch disposed in the second duct, and a third switch disposed between the first duct and the second duct; wherein,

[0023] In the first working mode, the first switch is closed to control the first duct to be closed, the second switch is opened to control the second duct to be opened, and the third switch is opened to control the first duct and the second duct to be connected;

[0024] In the second working mode, the first switch is opened to control the first duct to be opened, the second switch is closed to control the second duct to be closed, and the third switch is closed to disconnect the first duct and the second duct;

[0025] In the third working mode, the first switch is closed to control the first duct to be closed, the second switch is opened to control the second duct to be opened, and the third switch is closed to disconnect the first duct and the second duct.

[0026] Optionally, the first switch and the second switch are close to an outlet of the intake system, and the third switch is arranged between the precooling system and the turbocharger system.

[0027] In a second aspect, the present application also discloses an aircraft, comprising: an engine as described in any one of the above items.

[0028] In the embodiment of the present application, the engine may include an intake system, a precooling system, a turbocharger system, a ramjet combustion system and an exhaust system, and may switch between the first working mode, the second working mode and the third working mode. In the first working mode, the incoming air may be pressurized by the turbocharger system and then burned into combustion gas in the turbocharger system and the ramjet combustion system, and finally expand in the exhaust system to generate thrust, so as to solve the problem that the existing ramjet engine cannot achieve zero-speed start. In the second working mode, the incoming air may be precooled by the precooling system, then enter the turbocharger system for pressurization, and burn into combustion gas in the turbocharger system and the ramjet combustion system, and finally expand in the exhaust system to generate thrust, so as to solve the problem of "thrust trap" existing in the existing combined engine. In the third working mode, the incoming air directly enters the ramjet combustion system through the second duct to become combustion gas, and finally expands in the exhaust system to generate thrust, so as to achieve high Mach flight. That is, the engine described in the embodiment of the present application can solve the problem of zero-speed starting and overcoming the "thrust trap", and achieve continuous, efficient, repeatable and low-cost operation.

[0029] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0031] Figure 1 is a structural schematic diagram of an engine described in an embodiment of the present application;

[0032] Figure 2 is a comparison chart of the unit thrust of the engine described in the embodiment of the present application and the existing combined engine as a function of Mach;

[0033] Figure 3 It is a comparison chart of the unit specific impulse of the engine described in the application embodiment and the existing combined engine with the change of Mach;

[0034] Figure 4 It is a schematic diagram of the mechanism of another engine described in an embodiment of the present application;

[0035] Figure 5 yes Figure 4 The structural schematic diagram of the engine shown is in the first working mode;

[0036] Figure 6 yes Figure 4 The structural schematic diagram of the engine shown is in the second working mode;

[0037] Figure 7 yes Figure 4 The structural schematic diagram of the engine shown is in the third working mode;

[0038] Figure 8 The engine described in the embodiment of the present application is Figure 5 PV cycle diagram of the working mode shown;

[0039] Fig. 9 The engine described in the embodiment of the present application is Figure 6 PV cycle diagram of the working mode shown;

[0040] Fig.10 The engine described in the embodiment of the present application is Figure 7 PV cycle diagram of the operating mode shown.

[0041] Figure markings: 10-intake system, 11-intake duct, 20-precooling system, 21-precooling fan, 22-heat exchanger, 30-turbocharger system, 31-axial compressor, 32-main combustion chamber, 33-turbine, 40-ramjet combustion system, 41-ramjet combustion chamber, 50-exhaust system, 51-first tail nozzle, 52-second tail nozzle, 60-first duct, 61-first switch, 70-second duct, 71-second switch, 72-third switch, 80-liquid circulation system, 81-liquid tank, 82-starting liquid pump, 83-hydraulic turbine, 84-low-pressure liquid pump, 85-high-pressure liquid pump. DETAILED DESCRIPTION

[0042] Embodiments of the present invention will be described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0043] The term "first" or "second" in the specification of the present application may include one or more of the features explicitly or implicitly. In the description of the present invention, unless otherwise specified, "plurality" means two or more. In addition, "and / or" in the specification means at least one of the connected objects, and the character " / " generally indicates that the objects connected before and after are in an "or" relationship.

[0044] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0045] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] Reference Figure 1 , shows a schematic diagram of the structure of an engine according to an embodiment of the present application, such as Figure 1 As shown, the engine may specifically include: an intake system 10, a precooling system 20, a turbocharging system 30, a ramjet combustion system 40, an exhaust system 50 and a liquid circulation system which are arranged in sequence; the engine has at least a first duct 60 and a second duct 70, the first duct 60 is at least connected to the precooling system 20, the second duct 70 is at least formed in the ramjet combustion system 40 and the turbocharging system 30, and the liquid circulation system 80 is respectively connected to the precooling system 20, the turbocharging system 30 and the ramjet combustion system 40; the engine has a first working mode, a second working mode and a third working mode; wherein, in the first working mode, the precooling system is closed, and the incoming air enters the turbocharging system 30 through the second duct 70 for supercharging. After that, it is burned into combustion gas in the turbocharger system 30 and the ramjet combustion system 40 respectively, and finally expands in the exhaust system to generate thrust; in the second working mode, the incoming air enters the precooling system 20 through the first duct 60 for precooling, then enters the turbocharger system 30 for supercharging, and is burned into combustion gas in the turbocharger system 30 and the ramjet combustion system 40 respectively, and finally expands in the exhaust system to generate thrust; in the third working mode, the incoming air directly enters the ramjet combustion system 40 through the second duct 70 to become combustion gas, and finally expands in the exhaust system to generate thrust.

[0047] In the embodiment of the present application, the engine may include an intake system 10, a precooling system 20, a turbocharger system 30, a ramjet combustion system and an exhaust system 50, and may switch between the first working mode, the second working mode and the third working mode. In the first working mode, the incoming air may be pressurized by the turbocharger system 30 and may be burned into combustion gas in the turbocharger system 30 and the ramjet combustion system 40 respectively, and finally expand in the exhaust system to generate thrust, so as to solve the problem that the existing ramjet engine cannot achieve zero-speed start. In the second working mode, the incoming air may be precooled by the precooling system 20, and then enter the turbocharger system 30 for pressurization, and may be burned into combustion gas in the turbocharger system 30 and the ramjet combustion system 40 respectively, and finally expand in the exhaust system to generate thrust, so as to solve the problem of "thrust trap" existing in the existing combined engine. In the third working mode, the incoming air directly enters the ramjet combustion system 40 through the second duct 70 to become combustion gas, and finally expands in the exhaust system to generate thrust, so as to achieve high Mach flight. That is, the engine described in the embodiment of the present application can solve the problem of zero-speed starting and overcoming the "thrust trap", and achieve continuous, efficient, repeatable and low-cost operation.

[0048] Moreover, in the embodiment of the present application, a liquid circulation system 80 is provided in the engine, and the liquid circulation system 80 is respectively connected to the precooling system 20, the turbocharging system 30 and the ramjet combustion system 40, and driven by the liquid circulation system 80. In this way, it is possible to avoid the operation of providing a compressor in the precooling system 20, simplify the structure of the precooling system 20, and thereby achieve the purpose of simplifying the internal structure of the engine and reducing the volume of the engine.

[0049] like Figure 1 As shown, the incoming air can be Figure 1 The direction indicated by the middle arrow enters the interior of the engine through the intake system 10, and after combustion in the turbocharger system 30 and / or the ramjet combustion system 40 inside the engine, it is finally discharged through the exhaust system 50 to form thrust. The engine may be provided with a first duct 60 and a second duct 70 for air circulation. The first duct 60 may serve as an inner duct of the engine to guide the incoming air to the precooling system 20. The second duct 70 may serve as an outer duct of the engine to guide the incoming air to the turbocharger system 30 or the ramjet combustion system 40.

[0050] In the embodiment of the present application, the operating mode of the engine corresponds to the flight speed of the aircraft, so that the engine can operate efficiently and stably at different flight speeds.

[0051] Specifically, when the speed of the aircraft is 0-2 Mach, the engine operates in the first working mode. The first working mode is the turbocharging mode. In this working mode, the incoming air enters the turbocharging system 30 through the second duct 70 and is pressurized, and then burns into combustion gas in the turbocharging system 30 and the ramjet combustion system 40, and finally expands in the exhaust system to generate thrust. Since the incoming air is pressurized by the turbocharging system 30 and then burns and expands to generate thrust, zero-speed starting can be achieved, solving the problem of the existing ramjet engine that cannot start at zero speed.

[0052] When the speed of the aircraft is Mach 2-4, the engine operates in the second working mode. The second working mode is a precooling mode. In this working mode, the incoming air first enters the precooling system 20 through the first duct 60 for precooling. The precooling system 20 reduces the total temperature and total pressure of the incoming air at Mach 2-4, so that the axial compressor 31 in the subsequent turbocharger system 30 can work efficiently at a high Mach number. In this way, the problem of "thrust trap" existing in the existing combined engine at Mach 2-4 can be overcome.

[0053] When the speed of the aircraft is Mach 4-6, the engine operates in the third working mode. The third working mode is the ramjet mode. In this working mode, the high-speed incoming air is pressurized from the second duct 70 and directly enters the ramjet combustion system 40 and is mixed with the fuel for combustion and then directly discharged from the exhaust system 50. The thrust is relatively large, and the high-speed flight of the aircraft can be achieved.

[0054] Reference Figure 2 , which shows a comparison of the unit thrust of the engine described in the embodiment of the present application and the existing combined engine with Mach change. Figure 3 , showing a comparison chart of the change of unit specific impulse with Mach of the engine described in the embodiment of the present application relative to the existing combined engine.

[0055] like Figure 2 , Figure 3 As shown, the existing turboramjet combination engine (TBCC), air turbine rocket combination engine (ATR) and rocket ramjet combination engine (RBCC) cannot effectively solve the problem of "thrust trap" at a flight speed of 2-4 Mach. The engine provided in this application can achieve continuous, efficient and repeatable operation at 0~6Ma, effectively solving the problem of "thrust trap". Since the engine provided in the embodiment of this application can achieve efficient, continuous, repeatable and low-cost operation, it is the power equipment of future high Mach number aircraft, and can even open up new ideas for new air and space transportation systems. The social and economic benefits are huge.

[0056] Reference Figure 4, showing a schematic diagram of another engine structure described in an embodiment of the present application, referring to Figure 5 , showing Figure 4 The schematic diagram of the structure of the engine in the first working mode shown in FIG. Figure 6 , showing Figure 4 The schematic diagram of the structure of the engine in the second working mode shown in FIG. Figure 7 , showing Figure 4 The schematic diagram of the structure of the engine shown is in the third working mode.

[0057] like Figure 4 As shown, the precooling system 20 may specifically include: a precooling fan 21 and a heat exchanger 22 connected in sequence; wherein the precooling fan 21 is close to the outlet of the air inlet duct 11 of the air inlet system 10. In a specific application, after the incoming air passes through the air inlet duct 11 of the air inlet system 10 and enters the engine, it may enter the precooling fan 21 through the first duct 60. The incoming air may be depressurized and cooled by the precooling fan 21, and the temperature of the air flow may be further reduced by the heat exchanger 22. The precooling system 20 reduces the total temperature and pressure of the incoming air at Mach 2-4, thereby enabling the axial compressor 31 to work efficiently at a high Mach number.

[0058] like Figure 4 As shown, the turbocharger system 30 may include an axial compressor 31, a main combustion chamber 32, and a turbine 33 connected in sequence; wherein the axial compressor 31 is close to the outlet of the precooling system 20. In a specific application, after the incoming air enters the axial compressor 31, it can be pressurized by the axial compressor 31, and then enter the main combustion chamber 32 to burn and generate combustion gas, which can drive the turbine 33, output power to the high-pressure liquid pump 85, and finally be discharged from the exhaust system 50 to generate thrust.

[0059] In practical applications, turbocharging can improve the engine power and torque. Without changing the engine displacement, turbocharging can significantly improve the engine power and torque. Moreover, turbocharging can also make the engine combustion more efficient, saving 3% to 5% of fuel, thereby improving fuel economy.

[0060] like Figure 4As shown, the liquid circulation system 80 may specifically include: a liquid tank 81, a starting liquid pump 82, a hydraulic turbine 83, a low-pressure liquid pump 84 and a high-pressure liquid pump 85; wherein the liquid tank 81 is connected to one end of the heat exchanger 22 through the starting liquid pump 82, the other end of the heat exchanger 22 is connected to the high-pressure liquid pump 85 through the low-pressure liquid pump 84, and the hydraulic turbine 83 is connected between the high-pressure liquid pump 85 and the liquid tank 81; the precooling fan 21 is connected to the low-pressure liquid pump 84 through a drive shaft to drive the low-pressure liquid pump 84; the turbine 33 is connected to the high-pressure liquid pump 85 through a drive shaft to drive the high-pressure liquid pump 85; the hydraulic turbine 83 is connected to the axial flow compressor 31 through a drive shaft to drive the axial flow compressor 31.

[0061] In practical applications, by directly driving the low-pressure liquid pump 84 through the precooling fan 21, it is possible to avoid using an additional separate driving mechanism to drive the low-pressure liquid pump 84, and by directly driving the high-pressure liquid pump through the turbine 33, it is possible to avoid using an additional separate driving mechanism to drive the high-pressure liquid pump 85. Thus, the number of parts inside the engine can be reduced and the internal structure of the engine can be simplified. After the liquid pressurized by the low-pressure liquid pump 84 and the high-pressure liquid pump 85 in turn can enter the hydraulic turbine 83, the hydraulic turbine 83 can provide energy for the axial flow compressor 31 to drive the axial flow compressor 31 to work.

[0062] In some optional embodiments of the present application, the heat exchanger 22 is a liquid-cooled heat exchanger, and the liquid circulating in the liquid circulation system 80 can be used as the liquid cooling medium of the heat exchanger 22. Compared with an air-cooled heat exchanger, since the liquid cooling medium in the liquid-cooled heat exchanger has a high density and a high heat exchange efficiency, when the heat exchanger 22 is a liquid-cooled heat exchanger, the volume can be greatly reduced.

[0063] In the embodiment of the present application, the liquid circulation system 80 can not only be used to drive the axial flow compressor 31 to work, so that the axial flow compressor 31 can integrate the functions of the low-pressure compressor and the high-pressure compressor, reduce the number of compressors in the engine, and simplify the internal structure of the engine. At the same time, the liquid circulation system 80 can also be used to participate in the circulation of the liquid medium of the heat exchanger 22 to improve the cooling effect of the heat exchanger 22 on the air flow.

[0064] For example, the liquid circulation system 80 may include but is not limited to water, coolant and other liquids. The embodiment of the present application does not specifically limit the type of circulation in the liquid circulation system 80.

[0065] like Figure 4As shown, the ramjet combustion system 40 may specifically include: a ramjet combustion chamber 41 and an axial flow compressor 31; wherein the ramjet combustion chamber 41 is connected to the outlet of the axial flow compressor 31. In a specific application, after the incoming air enters the axial flow compressor 31, it may be pressurized by the axial flow compressor 31, and then enter the ramjet combustion chamber 41 to burn and generate combustion gas, and the combustion gas is discharged from the exhaust system 50 to generate thrust.

[0066] like Figure 4 As shown, the exhaust system 50 may specifically include: a first tail nozzle 51 and a second tail nozzle 52; wherein the first tail nozzle 51 is connected to the turbine 33, and is used to discharge the gas generated by the combustion of the fuel in the main combustion chamber 32 to form thrust. The second tail nozzle 52 is connected to the ramjet combustion chamber 41, and is used to discharge the gas generated by the combustion of the fuel in the ramjet combustion chamber 41 to form thrust.

[0067] like Figures 5 to 7 As shown, the engine further includes: a first switch 61 disposed in the first duct 60 , a second switch 71 disposed in the second duct 70 , and a third switch 72 disposed between the first duct 60 and the second duct 70 .

[0068] exist Figure 5 In the first working mode shown, the first switch 61 is closed to control the first duct 60 to be closed, the second switch 71 is opened to control the second duct 70 to be opened, and the third switch 72 is opened to control the first duct 60 to be connected to the second duct 70. In this way, the incoming air can enter the second duct 70 through the intake duct 11 and enter the axial compressor 31 through the second duct 70.

[0069] exist Figure 6 In the second working mode shown, the first switch 61 is opened to control the first duct 60 to be opened, the second switch 71 is closed to control the second duct 70 to be closed, and the third switch 72 is closed to disconnect the first duct 60 from the second duct 70. In this way, the incoming air can enter the first duct 60 through the air intake duct 11, and enter the precooling fan 21 through the first duct 60.

[0070] exist Figure 7 In the third working mode shown, the first switch 61 is closed to control the first duct 60 to be closed, the second switch 71 is opened to control the second duct 70 to be opened, and the third switch 72 is closed to disconnect the first duct 60 and the second duct 70. In this way, the incoming air can enter the second duct 70 through the intake duct 11 and directly enter the ramjet combustion chamber 41 through the second duct 70.

[0071] Optionally, the first switch 61 and the second switch 71 are close to the outlet of the intake system 10, so that the first switch 61 controls the opening and closing of the first duct 60, and the second switch 71 controls the opening and closing of the second duct 70. The third switch 72 is arranged between the precooling system 20 and the turbocharger system 30, so that the third switch 72 controls the air flow in the second duct 70 to enter the axial compressor 31 or the ramjet combustion chamber 41.

[0072] In a specific application, when the speed of the aircraft is 0-2 Mach, the engine can Figure 5 The first working mode shown works. In this mode, the precooling system 20 is closed; the incoming air enters the second duct 70, and the third switch 72 plate is in the open state, and the airflow in the second duct 70 directly enters the axial compressor 31. After being pressurized by the axial compressor 31, the air flow is divided into two streams: the first stream enters the main combustion chamber 32 for combustion, and the gas drives the turbine 33 to do work to provide energy for the high-pressure liquid pump 85 at the front end, and then the gas is discharged from the first tail nozzle 51 to generate the first part of the engine thrust; the second stream of air enters the ramjet combustion chamber 41 of the outer ring of the main combustion chamber 32 and is mixed with the fuel and burned, and then is directly discharged from the second tail nozzle 52 to generate the second part of the thrust. The combined force of the two parts of the thrust is the total thrust of this type of engine. In this working mode, the liquid circulation system 80 is partially opened, and the liquid first flows out of the liquid tank 81, is pressurized by the start-up liquid pump 82 to obtain an initial velocity, and then enters the high-pressure liquid pump 85 to be pressurized to become high-pressure liquid. The high-pressure liquid drives the hydraulic turbine 83 to provide energy for the axial flow compressor 31, and finally unloads the high pressure and enters the liquid tank 81.

[0073] When the speed of the aircraft is 2-4 Mach, the engine can Figure 6The second working mode shown in the figure works. In this mode, the second duct 70 is closed, the incoming air enters the first duct 60, then flows through the precooling fan 21 to reduce the pressure and temperature, and then flows through the heat exchanger 22 to further reduce the air flow temperature. The precooling system 20 reduces the total temperature and pressure of the incoming air at Mach 2-4, so that the axial compressor 31 can work efficiently at a high Mach number. The air flowing into the axial compressor 31 is further pressurized and divided into two streams of air: the first stream enters the main combustion chamber 32 for combustion, and the gas drives the turbine 33 to do work to provide energy for the high-pressure liquid pump 85 at the front end, and then the gas is discharged from the first tail nozzle 51 to generate the first part of the engine's thrust; the second stream of air enters the ramjet combustion chamber 41 on the outer ring of the main combustion chamber 32 and is mixed with the fuel and burned, and then is directly discharged from the second tail nozzle 52 to generate the second part of the thrust. The combined force of the two parts of thrust is the total thrust of this type of engine. In this working mode, the liquid circulation system 80 is fully opened, and the liquid first flows out of the liquid tank 81, is pressurized by the start-up liquid pump 82 to obtain an initial velocity, and then enters the low-pressure liquid pump 84 and the high-pressure liquid pump 85 in turn to be pressurized to become high-pressure liquid. The high-pressure liquid drives the hydraulic turbine 83 to provide energy for the axial flow compressor 31, and finally unloads the high pressure and enters the liquid tank 81.

[0074] When the speed of the aircraft is 4-6 Mach, the engine can Figure 7 The third working mode shown in the figure works. In this mode, the first duct 60 is completely closed, that is, the precooling system 20 and the turbocharger system 30 are both closed; the high-speed incoming air enters the second duct 70 and is pressurized, directly enters the ramjet combustion chamber 41, mixes with the fuel, and is burned, and then is directly discharged from the second tail nozzle 52 to generate the total thrust of the engine. In this working mode, the liquid circulation system 80 is completely closed.

[0075] Reference Figure 8 , showing the engine described in the embodiment of the present application Figure 5 Refer to the PV cycle diagram of the working mode shown in Fig. 9 , showing the engine described in the embodiment of the present application Figure 6 Refer to the PV cycle diagram of the working mode shown in Fig.10 , showing the engine described in the embodiment of the present application Figure 7 PV cycle diagram of the operating mode shown.

[0076] It should be noted that Figures 8 to 10 The PV cycle diagram shown is based on the following assumptions: 1. The airflow or gas involved in the embodiments of the present application is a perfect gas, and the flow is one-dimensional and steady; 2. The airflow has its own constant-pressure specific heat capacity, constant-volume specific heat capacity and specific heat ratio when flowing through the air inlet 11, the precooling fan 21, the axial compressor 31, the turbine 33 and the tail nozzle; 3. When the airflow flows through the combustion chamber, the afterburner and the mixing chamber, the value is changing.

[0077] For ease of explanation, different cross sections may be taken at different locations within the engine. Figures 4 to 6 As shown, section 0 is the air far field, section 1 is the inlet of the air inlet 11, section 2 is the outlet of the air inlet 11, section 2.1 is the outlet of the precooling fan 21, section 2.2 is the outlet of the heat exchanger 22, section 3 is the outlet of the axial compressor 31, section 5 is the outlet of the main combustion chamber 32, section 6.1 is the outlet of the turbine 33, section 6.2 is the outlet of the ramjet combustion chamber 41, section 9.2 is the outlet of the tail nozzle, sections 7.1, 8.1 and 9.1 are the inlet, throat and outlet of the convergent-divergent tail nozzle; in the liquid path, section 4.1 is the outlet of the starting liquid pump 82, section 4.2 is the outlet of the heat exchanger 22, section 4.3 is the outlet of the low-pressure liquid pump 84, section 4.4 is the outlet of the high-pressure liquid pump 85, and section 4.5 is the outlet of the hydraulic turbine 83.

[0078] like Figure 8 As shown, in the first working mode: 1-2 is the isentropic compression process in the air inlet 11; 2-3 is the isentropic compression process in the axial compressor 31; 3-5 is the isobaric combustion process of air with a relative air entrainment amount of e in the main combustion chamber 32; 5-6.1 is the isentropic expansion process of air with a relative air entrainment amount of e in the turbine 33; 6.1-9.2 is the isentropic expansion process of air with a relative air entrainment amount of e in the first tail nozzle 51; 3-6.2 is the isobaric combustion process of air with a relative air entrainment amount of 1-e in the ramjet combustion chamber 41; 6.2-9.1 is the isentropic expansion process of air with a relative air entrainment amount of 1-e in the second tail nozzle 52; 9.1-1 is the isobaric heat release process in the atmosphere.

[0079] like Fig. 9 As shown, in the second working mode: 1-2.1 is the isentropic expansion process in the precooling fan 21; 2.1-2.2 is the isobaric heat release process in the heat exchanger 22; 2.2-3 are the isentropic compression processes in the axial compressor 31; 3-5 are the isobaric combustion processes of air with a relative air entrainment amount of e in the main combustion chamber 32; 5-6.1 are the isentropic expansion processes of air with a relative air entrainment amount of e in the turbine 33; 6.1-9.2 are the isentropic expansion processes of air with a relative air entrainment amount of e in the first tail nozzle 51; 3-6.2 are the isobaric combustion processes of air with a relative air entrainment amount of 1-e in the ramjet combustion chamber 41; 6.2-9.1 are the isentropic expansion processes of air with a relative air entrainment amount of 1-e in the second tail nozzle 52; 9.1-1.2 are the isobaric heat release processes in the atmosphere.

[0080] like Fig.10As shown, in the ramjet mode, 1-2 is the isentropic compression process in the air inlet 11; 2-6.2 is the isobaric combustion process in the ramjet combustion chamber 41; 6.2-9.1 is the isentropic expansion process in the second tail nozzle 52; and 9.1-1 is the isobaric heat release process in the atmosphere.

[0081] In summary, the engine described in the embodiment of the present application can at least include the following advantages:

[0082] In the embodiment of the present application, the engine may include an intake system, a precooling system, a turbocharger system, a ramjet combustion system and an exhaust system, and may switch between the first working mode, the second working mode and the third working mode. In the first working mode, the incoming air may be pressurized by the turbocharger system and then burned into combustion gas in the turbocharger system and the ramjet combustion system, and finally expand in the exhaust system to generate thrust, so as to solve the problem that the existing ramjet engine cannot achieve zero-speed start. In the second working mode, the incoming air may be precooled by the precooling system, then enter the turbocharger system for pressurization, and burn into combustion gas in the turbocharger system and the ramjet combustion system, and finally expand in the exhaust system to generate thrust, so as to solve the problem of "thrust trap" existing in the existing combined engine. In the third working mode, the incoming air directly enters the ramjet combustion system through the second duct to become combustion gas, and finally expands in the exhaust system to generate thrust, so as to achieve high Mach flight. That is, the engine described in the embodiment of the present application can solve the problem of zero-speed starting and overcoming the "thrust trap", and achieve continuous, efficient, repeatable and low-cost operation.

[0083] The present application also provides an aircraft, which may include the engine described in any of the above embodiments. The aircraft may include but is not limited to at least one of an aircraft, a spacecraft, and a high Mach aircraft. The present application does not specifically limit the type of the aircraft.

[0084] It should be noted that in the embodiment of the present application, the structure of the engine of the aircraft is the same as the structure of the engine described in any of the above embodiments, and its beneficial effects are also similar, which will not be repeated here.

[0085] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0086] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the invention, and the scope of the invention is limited by equivalents.

Claims

1. An engine for an aircraft, characterized in that: The engine comprises: an intake system (10), a precooling system (20), a turbocharging system (30), a ramjet combustion system (40), an exhaust system (50), and a liquid circulation system (80) which are arranged in sequence; The engine has at least a first duct (60) and a second duct (70), the first duct (60) being formed at least in the precooling system (20), and the liquid circulation system (80) being respectively connected to the precooling system (20), the turbocharger system (30) and the ramjet combustion system (40); The precooling system (20) comprises: a precooling fan (21) and a heat exchanger (22) connected in sequence; the precooling fan (21) is close to the outlet of the air intake system (10); The turbocharger system (30) comprises: an axial flow compressor (31), a main combustion chamber (32), and a turbine (33) connected in sequence; the axial flow compressor (31) is close to an outlet of the precooling system (20); The liquid circulation system (80) comprises: a liquid tank (81), a starting liquid pump (82), a hydraulic turbine (83), a low-pressure liquid pump (84), and a high-pressure liquid pump (85); The liquid tank (81) is connected to one end of the heat exchanger (22) via the starting liquid pump (82); the other end of the heat exchanger (22) is connected to the high-pressure liquid pump (85) via the low-pressure liquid pump (84); the hydraulic turbine (83) is connected between the high-pressure liquid pump (85) and the liquid tank (81); the precooling fan (21) is connected to the low-pressure liquid pump (84) via a drive shaft to drive the low-pressure liquid pump (84); the turbine (33) is connected to the high-pressure liquid pump (85) via a drive shaft to drive the high-pressure liquid pump (85); the hydraulic turbine (83) is connected to the axial flow compressor (31) via a drive shaft to drive the axial flow compressor (31); The engine has a first working mode, a second working mode and a third working mode; In the first working mode, the precooling system is closed, and the incoming air enters the turbocharger system (30) through the second duct (70) for supercharging, and then burns into combustion gas in the turbocharger system (30) and the ramjet combustion system (40), and finally expands in the exhaust system to generate thrust; in the second working mode, the incoming air enters the precooling system (20) through the first duct (60) for precooling, and then enters the turbocharger system (30) for supercharging, and then burns into combustion gas in the turbocharger system (30) and the ramjet combustion system (40), and finally expands in the exhaust system to generate thrust; in the third working mode, the incoming air directly enters the ramjet combustion system (40) through the second duct (70) for supercharging, and finally burns into combustion gas in the turbocharger system (30) and the ramjet combustion system (40), and finally expands in the exhaust system to generate thrust.

2. The engine according to claim 1, characterized in that The working mode of the engine corresponds to the flight speed of the aircraft; wherein, When the speed of the aircraft is 0-2 Mach, the engine operates in the first working mode; when the speed of the aircraft is 2-4 Mach, the engine operates in the second working mode; when the speed of the aircraft is 4-6 Mach, the engine operates in the third working mode.

3. The engine according to claim 1, characterized in that The heat exchanger (22) is a liquid-cooled heat exchanger.

4. The engine according to claim 1, characterized in that The ramjet combustion system (40) comprises a ramjet combustion chamber (41), wherein the ramjet combustion chamber (41) is connected to an outlet of the axial flow compressor (31).

5. The engine according to claim 4, characterized in that The exhaust system (50) comprises: a first tail nozzle (51) and a second tail nozzle (52); wherein: The first tail nozzle (51) is connected to the turbine (33), and the second tail nozzle (52) is connected to the ramjet combustion chamber (41).

6. The engine according to claim 1, characterized in that The engine further comprises: a first switch (61) arranged at the first duct (60), a second switch (71) arranged at the second duct (70), and a third switch (72) arranged between the first duct (60) and the second duct (70); wherein: In the first working mode, the first switch (61) is closed to control the first duct (60) to be closed, the second switch (71) is opened to control the second duct (70) to be opened, and the third switch (72) is opened to control the first duct (60) and the second duct (70) to be connected; In the second working mode, the first switch (61) is opened to control the first duct (60) to be opened, the second switch (71) is closed to control the second duct (70) to be closed, and the third switch (72) is closed to disconnect the connection between the first duct (60) and the second duct (70); In the third working mode, the first switch (61) is closed to control the first duct (60) to be closed, the second switch (71) is opened to control the second duct (70) to be opened, and the third switch (72) is closed to disconnect the connection between the first duct (60) and the second duct (70).

7. The engine according to claim 6, characterized in that The first switch (61) and the second switch (71) are located close to an outlet of the air intake system (10), and the third switch (72) is disposed between the precooling system (20) and the turbocharger system (30).

8. An aircraft, characterized in that: The aircraft comprises: the engine according to any one of claims 1 to 7.

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