An engine and aircraft

Abstract

The embodiment of the application provides an engine and an aircraft. The engine comprises an air intake system, a pre-cooling supercharging system, a turbocharging system, a ram combustion system and an exhaust system; the pre-cooling supercharging system and the ram combustion system comprise a high-pressure compressor, the turbocharging system comprises a low-pressure compressor, in a first working mode, airflow enters the turbocharging system for supercharging, is combusted into gas in the turbocharging system and the ram combustion system, and finally expands in the exhaust system to generate thrust; in a second working mode, airflow is pre-cooled and supercharged by the pre-cooling supercharging system, then enters the turbocharging system for supercharging, is combusted into gas in the turbocharging system and the ram combustion system, and finally expands in the exhaust system to generate thrust; in a third working mode, airflow is combusted into gas by the ram combustion system, and finally expands in the exhaust system to generate thrust. The engine solves the problems of zero-speed starting and crossing "thrust trap", and realizes continuous and efficient operation.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of engines, and particularly relates to an engine and an aircraft. BACKGROUND

[0002] With the development of science and technology, aerospace engines have developed for more than 100 years and formed three branches: aviation turbine engines, rocket engines and ramjet engines. Due to high technical maturity, the three types of engines are widely used in their respective fields, but it is difficult to use them across fields. The turbine engine has very low efficiency when cruising at high Mach numbers; the rocket engine has small specific impulse and large propellant consumption, and it is difficult to operate for a long time; the ramjet engine cannot start at zero speed. However, the further development of aerospace industry requires that the power system must meet the requirements of continuous high-efficiency work in a wide speed range (Mach number 0-6 and higher) and a large airspace (0-30 km and higher) and be reusable. Obviously, the above three types of engines are difficult to directly meet the requirements, and people naturally think of combining them, that is, a combined engine.

[0003] However, the existing combined engines have their own characteristics, but they cannot efficiently solve the "thrust trap (2-4 Mach)" problem, and it is difficult to achieve continuous high-efficiency and reusable work in the range of 0-6 Mach. SUMMARY

[0004] The application aims to provide an engine and an aircraft to solve the problem that the existing combined engine cannot efficiently solve the "thrust trap" problem and is difficult to achieve continuous high-efficiency and reusable work in the range of 0-6 Mach.

[0005] To solve the above technical problems, the application is implemented as follows:

[0006] In a first aspect, the application discloses an engine for an aircraft, comprising: an air intake system, a pre-cooling supercharging system, a turbocharging system, a ramjet combustion system and an exhaust system arranged in sequence, wherein the pre-cooling supercharging system and the ramjet combustion system at least comprise a high-pressure compressor, and the turbocharging system at least comprises a low-pressure compressor.

[0007] The engine has at least a first duct and a second duct, wherein the first duct is formed at least by the pre-cooling supercharging system and the turbocharging system, and the second duct is formed at least by the ramjet combustion system.

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

[0009] In the first working mode, the pre-cooling increase system is closed, the incoming airflow enters the turbocharging system through the second duct, is pressurized, and is combusted into gas in the turbocharging system and the ramjet combustion system respectively, and finally expands in the exhaust system to generate thrust; in the second working mode, the incoming airflow enters the pre-cooling increase system through the first duct, is pre-cooled and pressurized, and then enters the turbocharging system, and is combusted into gas in the turbocharging system and the ramjet combustion system respectively, and finally expands in the exhaust system to generate thrust; in the third working mode, the incoming airflow enters the ramjet combustion system directly through the second duct, is combusted into gas, and finally expands in the exhaust system to generate thrust.

[0010] Optionally, the working 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 works in the first working mode, when the speed of the aircraft is 2-4 Mach, the engine works in the second working mode, and when the speed of the aircraft is 4-6 Mach, the engine works in the third working mode.

[0012] Optionally, the engine further comprises: a first switch arranged in the first duct, a second switch arranged in the second duct, and a third switch arranged between the first duct and the second duct; wherein,

[0013] 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 communicated;

[0014] 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 connection between the first duct and the second duct;

[0015] 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 connection between the first duct and the second duct.

[0016] Optionally, the first switch and the second switch are close to the outlet of the air intake system, and the third switch is arranged between the pre-cooling increase system and the turbocharging system.

[0017] Optionally, the pre-cooling increase system comprises: a pre-cooling fan, a heat exchanger, and the high-pressure compressor connected in sequence; wherein,

[0018] The pre-cooling fan is close to the outlet of the air intake system.

[0019] Optionally, the pre-cooling fan is connected with the high-pressure compressor through a drive shaft, and the pre-cooling fan is used to drive the high-pressure compressor to work.

[0020] Optionally, the turbocharging system comprises the low-pressure compressor, the main combustion chamber and the turbine connected in sequence; wherein,

[0021] The low-pressure compressor is arranged between the high-pressure compressor and the heat exchanger.

[0022] Optionally, the turbine is connected with the low-pressure compressor through a drive shaft, and the turbine is used to drive the low-pressure compressor to work.

[0023] Optionally, the ram combustion system comprises the ram combustion chamber and the high-pressure compressor; wherein, the ram combustion chamber is connected with the outlet of the high-pressure compressor.

[0024] Optionally, the exhaust system comprises a first tail nozzle and a second tail nozzle; wherein,

[0025] The first tail nozzle is connected with the turbine, and the second tail nozzle is connected with the ram combustion chamber.

[0026] In a second aspect, the application further discloses an aircraft, comprising the engine according to any one of the above.

[0027] In the embodiments of the application, the engine can comprise an air intake system, a pre-cooling turbocharging system, a turbocharging system, a ram combustion system and an exhaust system, and can be switched between the first working mode, the second working mode and the third working mode. In the first working mode, the airflow can be pressurized by the turbocharging system, and then combusted into gas in the turbocharging system and the ram combustion system, and finally expanded in the exhaust system to generate thrust, so as to solve the problem that the existing ramjet engine cannot start at zero speed. In the second working mode, the airflow can be pre-cooled and pressurized by the pre-cooling turbocharging system, and then pressurized by the turbocharging system, and then combusted into gas in the turbocharging system and the ram combustion system, and finally expanded 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 airflow directly enters the ram combustion system through the second duct to become gas, and finally expands in the exhaust system to generate thrust, so as to realize high-Mach flight. That is, the engine according to the embodiments of the application can solve the problems of zero-speed starting and crossing "thrust trap", and realize continuous, efficient, repeatable and low-cost operation.

[0028] Moreover, since the pre-cooling supercharging system and the ram combustion system comprise a high-pressure compressor, and the turbocharging system comprises a low-pressure compressor, the rotation speed of the high-pressure compressor is greater than that of the low-pressure compressor. Test data show that, in the case that the rotation speed of the high-pressure compressor in the pre-cooling supercharging system and the ram combustion system is greater than that of the low-pressure compressor in the turbocharging system, the engine can have a better cycle efficiency, and the working efficiency of the engine is further improved.

[0029] Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following and / or can be learned by practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0030] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description, including the appended drawings.

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

[0032] Figure 2 is a comparison diagram of the unit thrust of an engine according to an embodiment of the present application relative to that of an existing combined engine with respect to Mach number;

[0033] Figure 3 is a comparison diagram of the unit specific impulse of an engine according to an embodiment of the present application relative to that of an existing combined engine with respect to Mach number;

[0034] Figure 4 is a structural schematic diagram of another engine according to an embodiment of the present application;

[0035] Figure 5 is a structural schematic diagram of an engine according to an embodiment of the present application; Figure 4 in a first working mode;

[0036] Figure 6 is a structural schematic diagram of an engine according to an embodiment of the present application; Figure 4 in a second working mode;

[0037] Figure 7 is a structural schematic diagram of an engine according to an embodiment of the present application; Figure 4 in a third working mode;

[0038] Figure 8 is a P-V cycle diagram of an engine according to an embodiment of the present application in the working mode shown in Figure 5 ;

[0039] Figure 9 is a P-V cycle diagram of an engine according to an embodiment of the present application in the working mode shown in Figure 6 ;

[0040] Figure 10 is the engine described in the embodiments of the present application in Figure 7 P-V cycle diagram of the working mode shown in FIG. 1.

[0041] Reference numerals: 10 - air intake system, 11 - air intake passage, 20 - pre-cooling supercharging system, 21 - pre-cooling fan, 22 - heat exchanger, 23 - high-pressure compressor, 30 - turbocharging system, 31 - low-pressure 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. DETAILED DESCRIPTION

[0042] Embodiments of the present application will be described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0043] The terms "first", "second" in the description and claims of the present application can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / ", generally indicates that the front and rear associated objects are in an "or" relationship.

[0044] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0045] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "linking" should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integral connection; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through intermediate medium, can be internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0046] Referring to Figure 1 , a structural schematic diagram of an engine is shown, as Figure 1 indicated, the engine can specifically include: an air intake system 10, a pre-cooling supercharging system 20, a turbocharging system 30, a ram combustion system 40 and an exhaust system 50 arranged in sequence, the pre-cooling supercharging system 20 and the ram combustion system 40 at least can include a high-pressure compressor 23, and the turbocharging system 30 at least can include a low-pressure compressor 31; the engine at least has a first duct 60 and a second duct 70, the first duct 60 at least communicates with the pre-cooling supercharging system 20 and the turbocharging system 30, and the second duct 70 at least is formed in the ram 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 pre-cooling supercharging system is closed, the incoming air enters the turbocharging system 30 through the second duct 70 for supercharging, and is combusted into gas in the turbocharging system 30 and the ram combustion system 40 respectively, and finally expands in the exhaust system to generate thrust; in the second working mode, the incoming air enters the pre-cooling supercharging system 20 for pre-cooling and supercharging through the first duct 60, and then enters the turbocharging system 30 for supercharging, and is combusted into gas in the turbocharging system 30 and the ram 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 ram combustion system 40 to become gas through the second duct 70, and finally expands in the exhaust system to generate thrust.

[0047] In this embodiment, the engine may include an intake system 10, a pre-cooling and supercharging system 20, a turbocharging system 30, a ramjet combustion system, and an exhaust system 50, and can switch between a first operating mode, a second operating mode, and a third operating mode. In the first operating mode, incoming air is pressurized by the turbocharging system 30 and then combusted into fuel gas in both the turbocharging system 30 and the ramjet combustion system 40, finally expanding in the exhaust system to generate thrust, thus solving the problem of existing ramjet engines being unable to achieve zero-speed start. In the second operating mode, incoming air is pre-cooled and pressurized by the pre-cooling and supercharging system 20 before entering the turbocharging system 30 for further pressurization, and then combusted into fuel gas in both the turbocharging system 30 and the ramjet combustion system 40, finally expanding in the exhaust system to generate thrust, thus solving the "thrust trap" problem of existing combined engines. In the third operating mode, incoming air directly enters the ramjet combustion system 40 through the second bypass 70 to become fuel gas, finally expanding in the exhaust system to generate thrust, thus achieving high Mach flight. In other words, the engine described in this application embodiment can solve the problem of zero-speed start-up and overcoming the "thrust trap", and achieve continuous, efficient, repeatable and low-cost operation.

[0048] Furthermore, the pre-cooling supercharging system 20 and the ramjet combustion system 40 include a high-pressure compressor 23, and the turbocharging system 30 includes a low-pressure compressor 31. The rotational speed of the high-pressure compressor 23 is greater than that of the low-pressure compressor 31. Test data shows that when the rotational speed of the high-pressure compressor 23 in the pre-cooling supercharging system 20 and the ramjet combustion system 40 is greater than that of the low-pressure compressor 31 in the turbocharging system 30, the engine can achieve better cycle efficiency, further improving the engine's operating efficiency.

[0049] Typically, the high-speed compressor rotor is the high-pressure compressor 23, and the low-speed compressor rotor is the low-pressure compressor 31. The maximum speed of the high-pressure compressor 23 is 30,000 rpm, and the maximum speed of the low-pressure compressor 31 can be 20,000 rpm. Specifically, in the embodiments of this application, the high-pressure compressor 23 and the low-pressure compressor 31 are only used to illustrate the speed of the compressors in the pre-cooled supercharging system 20, the turbocharging system 30, and the ramjet combustion system 40. That is, the speed of the compressor in the turbocharging system 30 is lower than the speed of the compressors in the pre-cooled supercharging system 20 and the ramjet combustion system 40. The embodiments of this application do not specifically limit the speed of the high-pressure compressor 23 and the low-pressure compressor 31.

[0050] like Figure 1 As shown, the incoming airflow can follow Figure 1The air flow enters the engine through the air inlet system 10 in the direction of the arrow, is combusted in the turbocharging system 30 and / or the ram combustion system 40 in the interior of the engine, and is finally discharged through the air outlet system 50 to form thrust. The interior of the engine can be provided with a first duct 60 and a second duct 70 for the flow of air. The first duct 60 can serve as an internal duct of the engine to guide the incoming air to the pre-cooling turbocharging system 20. The second duct 70 can serve as an internal duct of the engine to guide the incoming air to the turbocharging system 30 or the ram combustion system 40.

[0051] In the embodiments of the present application, the working mode of the engine corresponds to the flight speed of the aircraft, so that the engine can work efficiently and stably at different flight speeds.

[0052] Specifically, when the speed of the aircraft is 0-2 Mach, the engine works in the first working mode. The first working mode is a turbocharging mode, in which the incoming air enters the turbocharging system 30 for supercharging, and is combusted in the turbocharging system 30 and the ram combustion system 40 to become gas, which is finally expanded in the air outlet system to generate thrust. Since the incoming air is supercharged by the turbocharging system 30 before being combusted and expanded to generate thrust, zero-speed start-up can be achieved, and the problem of existing ramjet engines that cannot start at zero speed is solved.

[0053] When the speed of the aircraft is 2-4 Mach, the engine works in the second working mode. The second working mode is a pre-cooling turbocharging mode, in which the incoming air enters the pre-cooling turbocharging system 20 for pre-cooling and supercharging through the first duct 60. The pre-cooling turbocharging system 20 maintains the total pressure of the incoming air and reduces the total temperature of the incoming air at 2-3 Mach, and increases the total pressure of the incoming air and reduces the total temperature of the incoming air at 3-4 Mach, so that the subsequent turbocharging system 30 can work efficiently at high Mach numbers. In this way, the problem of "thrust trap" of existing combined engines at 2-4 Mach can be overcome.

[0054] When the speed of the aircraft is 4-6 Mach, the engine works in the third working mode. The third working mode is a ram mode, in which the high-speed incoming air is directly mixed with fuel in the ram combustion system 40 after being supercharged by the second duct 70, and is directly discharged from the air outlet system 50, so that the aircraft can fly at high speed.

[0055] Referring to Figure 2 , a comparison chart of the unit thrust of the engine of the embodiments of the present application relative to the unit thrust of the existing combined engine with Mach is shown. Referring to Figure 3The diagram shows a comparison of the specific impulse per unit speed of the engine described in this application embodiment versus that of a conventional combined engine, as a function of Mach. Figure 2 and Figure 3 As shown, the existing

[0056] like Figure 2 , Figure 3 As shown, existing turbo-ramjet combined engines (TBCC), air-turbo-rocket combined engines (ATR), and rocket-ramjet combined engines (RBCC) cannot efficiently solve the "thrust trap" problem at flight speeds of Mach 2-4. However, the engine provided in this application can achieve continuous, efficient, and repeatable operation from Mach 0 to Mach 6, effectively solving the "thrust trap" problem. Because the engine provided in this application can achieve efficient, continuous, repeatable, and low-cost operation, it is a potential power source for future high-Mach number aircraft and could even open up new aerospace transportation systems. The social and economic benefits are enormous.

[0057] Reference Figure 4 This shows a schematic diagram of the structure of another engine described in an embodiment of this application, with reference to... Figure 5 , showed Figure 4 The diagram shown is a structural schematic of the engine in its first operating mode. (Refer to...) Figure 6 , showed Figure 4 The diagram shown is a structural schematic of the engine in its second operating mode. (Refer to...) Figure 7 , showed Figure 4 The diagram shows the engine in its third operating mode.

[0058] like Figure 4 As shown, the pre-cooling and supercharging system 20 may specifically include: a pre-cooling fan 21, a heat exchanger 22, and a high-pressure compressor 23 connected in sequence; wherein, the pre-cooling fan 21 is located near the outlet of the intake duct 11 of the intake system 10. In specific applications, after the incoming air enters the engine through the intake duct 11 of the intake system 10, it can enter the pre-cooling fan 21 through the first bypass 60. The incoming air can be depressurized and cooled by the pre-cooling fan 21, and then its temperature can be further reduced by the heat exchanger 22. Then, it can be pressurized and heated by the high-pressure compressor 23. This process maintains the total pressure of the incoming air and reduces the total temperature of the incoming air at Mach 2-3; and increases the total pressure of the incoming air and reduces the total temperature of the incoming air at Mach 3-4, thereby enabling the high-pressure compressor 23 to operate efficiently at high Mach numbers.

[0059] Optionally, the precooling fan 21 is connected to the high-pressure compressor 23 via a drive shaft, and the precooling fan 21 can be used to drive the high-pressure compressor 23. This avoids the need for a separate drive mechanism to drive the high-pressure compressor 23, thereby reducing the number of internal components of the engine and simplifying its internal structure.

[0060] As shown in Figure 4 , the turbocharging system 30 can include a low-pressure compressor 31, a main combustion chamber 32 and a turbine 33 connected in sequence. In a specific application, after the airflow enters the low-pressure compressor 31, it can be pressurized by the low-pressure compressor 31, then enter the main combustion chamber 32 to burn and generate gas, which drives the turbine 33 to work to provide energy for the front-end low-pressure compressor 31, and then the gas is discharged from the exhaust system 50 to generate thrust.

[0061] In practical applications, turbocharging can improve the power and torque of the engine. Without changing the displacement of the engine, turbocharging can significantly improve the power and torque of the engine. Moreover, using turbocharging can also make the engine have higher combustion efficiency, which can save 3%~5% of fuel, thereby improving fuel economy.

[0062] Optionally, the turbine 33 is connected to the low-pressure compressor 31 through a drive shaft, and the turbine 33 can be used to drive the low-pressure compressor 31 to work. In this way, it is possible to avoid using a separate driving mechanism to drive the low-pressure compressor 31 to work, thereby reducing the number of parts inside the engine and simplifying the internal structure of the engine.

[0063] As shown in Figure 4 , the ramjet combustion system 40 can specifically include a ramjet combustion chamber 41 and a high-pressure compressor 23; wherein the ramjet combustion chamber 41 is connected with the outlet of the high-pressure compressor 23. In a specific application, after the airflow enters the high-pressure compressor 23, it can be pressurized by the high-pressure compressor 23, then enter the ramjet combustion chamber 41 to burn and generate gas, which is discharged from the exhaust system 50 to generate thrust.

[0064] As shown in Figure 4 , the exhaust system 50 can specifically include a first tail nozzle 51 and a second tail nozzle 52; wherein the first tail nozzle 51 is connected with the turbine 33, and the first tail nozzle 51 is used to discharge the gas generated by the combustion of fuel in the main combustion chamber 32 to form thrust. The second tail nozzle 52 is connected with the ramjet combustion chamber 41, and the second tail nozzle 52 is used to discharge the gas generated by the combustion of fuel in the ramjet combustion chamber 41 to form thrust.

[0065] As shown in Figures 5 to 7 , the engine further includes a first switch 61 arranged in the first duct 60, a second switch 71 arranged in the second duct 70, and a third switch 72 arranged between the first duct 60 and the second duct 70.

[0066] In Figure 5In 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 communicated. In this way, the airflow can enter the second duct 70 through the inlet 11 and then enter the low-pressure compressor 31 through the second duct 70.

[0067] 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 first duct 60 and the second duct 70. In this way, the airflow can enter the first duct 60 through the inlet 11 and then enter the pre-cooling fan 21 through the first duct 60. Figure 6 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 first duct 60 and the second duct 70. In this way, the airflow can enter the second duct 70 through the inlet 11 and then directly enter the ram combustor 41 through the second duct 70.

[0068] Figure 7 Optionally, the first switch 61 and the second switch 71 are arranged close to the outlet of the inlet system 10, so as to facilitate the first switch 61 to control the opening and closing of the first duct 60 and facilitate the second switch 71 to control the opening and closing of the second duct 70. The third switch 72 is arranged between the pre-cooling supercharging system 20 and the turbocharging system 30, so as to facilitate the third switch 72 to control the airflow in the second duct 70 to enter the low-pressure compressor 31 or the ram combustor 41.

[0069] In a specific application, when the speed of the aircraft is 0-2 Mach, the engine can work in the first working mode as shown. In this mode, the pre-cooling supercharging system 20 is closed; the airflow enters the second duct 70, and the third switch 72 is in an open state, so the airflow in the second duct 70 directly enters the low-pressure compressor 31. After being pressurized by the low-pressure compressor 31, the airflow is divided into two streams: the first stream enters the main combustor 32 to burn, the gas drives the turbine 33 to work to provide energy for the front low-pressure compressor 31, and then the gas is discharged from the first tail nozzle 51 to generate the first part of the thrust of the engine; the second stream of air enters the ram combustor 41 outside the main combustor 32 to mix with fuel and burn directly from the second tail nozzle 52 to generate the second part of the thrust. The resultant force of the two parts of the thrust is the total thrust of the engine.

[0070] When the speed of the aircraft is 2-4 Mach, the engine can work in the second working mode as shown. In this mode, the pre-cooling supercharging system 20 is opened; the airflow enters the first duct 60 through the inlet 11, and then enters the pre-cooling fan 21 through the first duct 60. After being pressurized by the pre-cooling fan 21, the airflow is divided into two streams: the first stream enters the main combustor 32 to burn, the gas drives the turbine 33 to work to provide energy for the front low-pressure compressor 31, and then the gas is discharged from the first tail nozzle 51 to generate the first part of the thrust of the engine; the second stream of air enters the ram combustor 41 outside the main combustor 32 to mix with fuel and burn directly from the second tail nozzle 52 to generate the second part of the thrust. The resultant force of the two parts of the thrust is the total thrust of the engine. Figure 5 When the speed of the aircraft is 2-4 Mach, the engine can work in the second working mode as shown. In this mode, the pre-cooling supercharging system 20 is opened; the airflow enters the first duct 60 through the inlet 11, and then enters the pre-cooling fan 21 through the first duct 60. After being pressurized by the pre-cooling fan 21, the airflow is divided into two streams: the first stream enters the main combustor 32 to burn, the gas drives the turbine 33 to work to provide energy for the front low-pressure compressor 31, and then the gas is discharged from the first tail nozzle 51 to generate the first part of the thrust of the engine; the second stream of air enters the ram combustor 41 outside the main combustor 32 to mix with fuel and burn directly from the second tail nozzle 52 to generate the second part of the thrust. The resultant force of the two parts of the thrust is the total thrust of the engine.

[0071] When the speed of the aircraft is 2-4 Mach, the engine can work in the second working mode as shown. In this mode, the pre-cooling supercharging system 20 is opened; the airflow enters the first duct 60 through the inlet 11, and then enters the pre-cooling fan 21 through the first duct 60. After being pressurized by the pre-cooling fan 21, the airflow is divided into two streams: the first stream enters the main combustor 32 to burn, the gas drives the turbine 33 to work to provide energy for the front low-pressure compressor 31, and then the gas is discharged from the first tail nozzle 51 to generate the first part of the thrust of the engine; the second stream of air enters the ram combustor 41 outside the main combustor 32 to mix with fuel and burn directly from the second tail nozzle 52 to generate the second part of the thrust. The resultant force of the two parts of the thrust is the total thrust of the engine.​Figure 6 The second operating mode is shown. In this mode, the second bypass 70 is closed, and the incoming air enters the first bypass 60. It then flows through the pre-cooling fan 21 to reduce its pressure and temperature, and then flows through the heat exchanger 22 to further reduce the airflow temperature. It is then pressurized and heated by the low-pressure compressor 31. This process maintains the total pressure of the incoming air and reduces its total temperature at Mach 2-3; at Mach 3-4, it increases the total pressure of the incoming air and reduces its total temperature, thereby improving the pressurization effect of the high-pressure compressor 23. After being pressurized by the low-pressure compressor 31, the air flows into the high-pressure compressor 23 for further pressurization and 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, providing energy to the low-pressure compressor 31 at the front end. The gas is then discharged from the first tail nozzle 51, generating the first part of the engine's thrust; the second stream enters the ramjet combustion chamber 41 on the outer ring of the main combustion chamber 32, mixes and burns with the fuel, and is then discharged directly from the second tail nozzle 52, generating the second part of the thrust. The resultant force of the two thrust components is the total thrust of this type of engine.

[0072] When the aircraft's speed is Mach 4-6, the engine can... Figure 7 The engine operates in the third operating mode shown. In this mode, the first bypass 60 is completely closed, that is, both the pre-cooling supercharging system 20 and the turbocharging system 30 are closed; the high-speed incoming air enters the second bypass 70, is pressurized, and then directly enters the ramjet combustion chamber 41 to mix and burn with fuel before being discharged directly from the second tail nozzle 52, generating the engine's total thrust.

[0073] Reference Figure 8 This illustrates the engine described in the embodiments of this application. Figure 5 The PV cycle diagram of the working mode is shown in the figure. Figure 9 This illustrates the engine described in the embodiments of this application. Figure 6 The PV cycle diagram of the working mode is shown in the figure. Figure 10 This illustrates the engine described in the embodiments of this application. Figure 7 The PV cycle diagram of the working mode is shown.

[0074] 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 this application is a complete gas, and the flow is one-dimensional and steady; 2. The airflow has its own isobaric specific heat capacity, isovolumetric specific heat capacity, and specific heat ratio when it flows through the intake duct 11, precooling fan 21, low-pressure compressor 31, turbine 33, and tail nozzle; 3. The values ​​change when the airflow flows through the combustion chamber, afterburner, and mixing chamber.

[0075] For ease of explanation, different cross-sections can be taken at different locations inside the engine. For example... Figures 4 to 6As shown, 0 section is air far field, 1 section is inlet of air inlet 11, 2 section is outlet of air inlet 11, 2.1 section is outlet of precooling fan 21, 2.2 section is outlet of heat exchanger 22, 3.1 section is outlet of low pressure compressor 31, 3.2 section is outlet of high pressure compressor 23, 4 section is outlet of ram combustor 41, 5 section is outlet of main combustor 32, 6 section is outlet of turbine 33, 9.2 section is outlet of first afterburner 51, 7.1, 8.1, 9.1 section is inlet, throat and outlet of convergent-divergent afterburner.

[0076] As shown in the first working mode: Figure 8 1.1-2 is an isentropic compression process in air inlet 11; 2-3.1 is an isentropic compression process in low pressure compressor 31; 3.1-5 is an isobaric combustion process of air with relative bleed air amount e in main combustor 32; 5-6 is an isentropic expansion process of air with relative bleed air amount e in turbine 33; 6-9.2 is an isentropic expansion process of air with relative bleed air amount e in first afterburner 51; 5-4 is an isobaric combustion process of air with relative bleed air amount 1-e in ram combustor 41; 4-9.1 is an isentropic expansion process of air with relative bleed air amount 1-e in second afterburner 52; 9.1-1.1 is an isobaric heat release process in atmosphere.

[0077] As shown in the second working mode: Figure 9 1.2-2.1 is an isentropic expansion process in precooling fan 21; 2.1-2.2 is an isobaric heat release process in heat exchanger 22; 2.2-3.1, 3.1-3.2 are isentropic compression processes in low pressure compressor 31 and high pressure compressor 23 respectively; 3.2-5 is an isobaric combustion process of air with relative bleed air amount e in main combustor 32; 5-6 is an isentropic expansion process of air with relative bleed air amount e in turbine 33; 6-9.2 is an isentropic expansion process of air with relative bleed air amount e in first afterburner 51; 3.2-4 is an isobaric combustion process of air with relative bleed air amount 1-e in ram combustor 41; 4-9.1 is an isentropic expansion process of air with relative bleed air amount 1-e in second afterburner 52; 9.1-1.2 is an isobaric heat release process in atmosphere.

[0078] As shown in the third working mode: Figure 10 1.3-2 is an isentropic compression process in air inlet 11; 2-4 is an isobaric combustion process in ram combustor 41; 4-9.1 is an isentropic expansion process in second afterburner 52.

[0079] In summary, the engine described in the embodiments of the present application can at least have the following advantages:

[0080] In the embodiments of the present application, the engine can include an air intake system, a pre-cooling supercharging system, a turbocharging system, a ram combustion system, and an exhaust system, and can switch between the first working mode, the second working mode, and the third working mode. In the first working mode, the airflow can be pressurized by the turbocharging system and then combusted into gas in the turbocharging system and the ram combustion system, respectively, and finally expanded in the exhaust system to generate thrust, so as to solve the problem that the existing ramjet engine cannot start at zero speed. In the second working mode, the airflow can be pre-cooled and pressurized by the pre-cooling supercharging system, then pressurized by the turbocharging system, and then combusted into gas in the turbocharging system and the ram combustion system, respectively, and finally expanded 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 airflow directly enters the ram combustion system through the second channel to become gas, and finally expands in the exhaust system to generate thrust, realizing high-Mach flight. That is, the engine in the embodiments of the present application can solve the problems of zero-speed starting and crossing "thrust trap", and realize continuous, efficient, repeatable, and low-cost operation.

[0081] Moreover, the pre-cooling supercharging system and the ram combustion system include high-pressure compressors, the turbocharging system includes a low-pressure compressor, and the rotation speed of the high-pressure compressor is greater than that of the low-pressure compressor. Test data show that, in the case that the rotation speed of the high-pressure compressor in the pre-cooling supercharging system and the ram combustion system is greater than that of the low-pressure compressor in the turbocharging system, the engine can have a better cycle efficiency, further improving the working efficiency of the engine.

[0082] The embodiments of the present application also provide a flying vehicle, which can include the engine of any of the above-mentioned embodiments. The flying vehicle can specifically include, but is not limited to, at least one of an aircraft, a spacecraft, and a high-Mach flying vehicle, and the type of the flying vehicle is not limited in the embodiments of the present application.

[0083] It should be noted that, in the embodiments of the present application, the structure of the engine of the flying vehicle is the same as that of the engine of any of the above-mentioned embodiments, and the beneficial effects are similar, which will not be repeated here.

[0084] In the description of the specification, reference to "one embodiment", "some embodiments", "an exemplary embodiment", "an example", "a specific example", or "some examples" means that a particular feature, structure, material, or characteristic being described is included in at least one embodiment or example of the application. The appearances of the phrases "in one embodiment", "in some embodiments", "in an exemplary embodiment", "an example", "a specific example", or "some examples" in various places in the specification are not necessarily referring to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0085] Although embodiments of the application have been illustrated and described, it will be clear to those of ordinary skill in the art that various changes, modifications, substitutions, and alterations can be made therein without departing from the principles and the spirit of the application. The scope of the application is limited only by the claims and the equivalents thereof.

Claims

1. An engine for an aircraft, characterised in that, The engine comprises: an air intake system (10), a pre-cooling turbocharging system (20), a turbocharging system (30), a ram combustion system (40) and an exhaust system (50) arranged in sequence, the pre-cooling turbocharging system (20) and the ram combustion system (40) at least comprising a high-pressure compressor (23), and the turbocharging system (30) at least comprising a low-pressure compressor (31); The pre-cooling turbocharging system (20) further comprises a pre-cooling fan (21) connected to the high-pressure compressor (23) through a drive shaft, and the pre-cooling fan (21) is used to drive the high-pressure compressor (23) to work; the turbocharging system (30) further comprises a turbine (33) connected to the low-pressure compressor (31) through a drive shaft, and the turbine (33) is used to drive the low-pressure compressor (31) to work; The engine has at least a first duct (60) and a second duct (70), the first duct (60) is formed at least in the pre-cooling turbocharging system (20) and the turbocharging system (30), and the second duct (70) is formed at least in the ram combustion system (40); The engine has a first working mode, a second working mode and a third working mode; In the first working mode, the pre-cooling turbocharging system is closed, the incoming air enters the turbocharging system (30) through the second duct (70) after being pressurized, is combusted into gas in the turbocharging system (30) and the ram combustion system (40) respectively, and finally expands in the exhaust system to generate thrust; in the second working mode, the incoming air enters the pre-cooling turbocharging system (20) after being pressurized through the first duct (60), then enters the turbocharging system (30) after being pressurized, is combusted into gas in the turbocharging system (30) and the ram 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 ram combustion system (40) through the second duct (70) to become gas, and finally expands in the exhaust system to generate thrust.

2. The engine of claim 1, wherein 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 works in the first working mode, when the speed of the aircraft is 2-4 Mach, the engine works in the second working mode, and when the speed of the aircraft is 4-6 Mach, the engine works in the third working mode.

3. The engine of claim 1, wherein The engine further comprises: a first switch (61) arranged in the first duct (60), a second switch (71) arranged in 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, the first duct (60) is controlled to be closed, the second switch (71) is opened, the second duct (70) is controlled to be opened, and the third switch (72) is opened, controlling the first duct (60) and the second duct (70) to be connected; In the second working mode, the first switch (61) is opened, the first duct (60) is controlled to be opened, the second switch (71) is closed, the second duct (70) is controlled to be closed, and the third switch (72) is closed, disconnecting the first duct (60) and the second duct (70). In the third working mode, the first switch (61) is closed, the first duct (60) is controlled to be closed, the second switch (71) is opened, the second duct (70) is controlled to be opened, and the third switch (72) is closed, disconnecting the first duct (60) and the second duct (70).

4. The engine of claim 3, wherein The first switch (61) and the second switch (71) are close to the outlet of the air intake system (10), and the third switch (72) is arranged between the pre-cooling supercharging system (20) and the turbocharging system (30).

5. The engine of claim 1, wherein The pre-cooling supercharging system (20) comprises, in sequence, a pre-cooling fan (21), a heat exchanger (22), and the high-pressure compressor (23); wherein, The pre-cooling fan (21) is close to the outlet of the air intake system (10).

6. The engine of claim 5, wherein The turbocharging system (30) comprises, in sequence, a low-pressure compressor (31), a main combustion chamber (32), and a turbine (33); wherein, The low-pressure compressor (31) is arranged between the high-pressure compressor (23) and the heat exchanger (22).

7. The engine of claim 6, wherein The ramjet combustion system (40) comprises a ramjet combustion chamber (41) and the high-pressure compressor (23); wherein, the ramjet combustion chamber (41) is connected with the outlet of the high-pressure compressor (23).

8. The engine of claim 7, wherein, The exhaust system (50) comprises a first tail nozzle (51) and a second tail nozzle (52); wherein, The first tail nozzle (51) is connected with the turbine (33), and the second tail nozzle (52) is connected with the ramjet combustion chamber (41).

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

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