Hybrid engine cooling system, cooling method, and hybrid engine

Abstract

The application provides a hybrid engine cooling system, a cooling method and a hybrid engine. The cooling system comprises a first cooling flow path and a second cooling flow path. One end of the first cooling flow path is communicated with a bleed air mechanism and is used for receiving low-temperature cooling air outside a cabin cover. One end of the second cooling flow path is communicated with a compressor and is used for receiving cooling seal air on the side of the compressor. The other ends of the first cooling flow path and the second cooling flow path are communicated with a third cooling flow path through a control valve. The third cooling flow path is divided into a first cooling branch and a second cooling branch. The first cooling branch is communicated with the side of a propulsion motor, and the second cooling branch is communicated with the side of a fulcrum seal system. When a working state of a prime mover is lower than an idle state, the control valve controls the first cooling flow path to supply air to the side of the propulsion motor and the side of the fulcrum seal system. When the working state of the prime mover is higher than the idle state, the control valve controls the second cooling flow path to supply air to the side of the propulsion motor and the side of the fulcrum seal system.

Description

Technical Field

[0001] This invention relates to the field of engine cooling sealing technology, specifically to a hybrid engine cooling system, cooling method, and hybrid engine. Background Technology

[0002] Against the backdrop of carbon neutrality and green aviation, the requirements for aero engines to reduce pollutant emissions and improve fuel economy are becoming increasingly stringent. Therefore, developing hybrid-powered aero engines is an important solution to meet increasingly stringent emission standards at present.

[0003] Compared to traditional aircraft engines, the electric drive unit in a hybrid power system includes a propulsion motor and a motor controller. Because the propulsion motor has high power and operates in high ambient temperatures (generally, the allowable ambient temperature for the propulsion motor does not exceed 120°C), cooling air needs to be introduced to cool and insulate the motor unit. Simultaneously, the support points of the propulsion motor and the prime mover need to be sealed tightly to prevent lubricating oil leakage.

[0004] As mentioned above, the current hybrid-electric aircraft engine motor cooling seal has the following defects:

[0005] I. The propulsion motors of hybrid-electric aircraft engines have high power, reaching megawatt levels or above. These high-power propulsion motors generate significant heat during operation, causing their temperature to rise rapidly. Excessive propulsion motor temperature can lead to coking of the cooling medium and may also cause demagnetization of the permanent magnets, affecting the safety and lifespan of the propulsion motor.

[0006] Second, in traditional aero engines, cooling and sealing gas is generally drawn from the compressor. However, in hybrid aero engines, the working states of the prime mover and the propulsion motor are not perfectly matched. There are situations where the motor is working but the prime mover is not. In this case, the compressor cannot provide cooling and sealing gas, and other mechanisms are needed to supply the gas. When the prime mover is working but the motor is not working, the propulsion motor also needs to be cooled and insulated because the operating environment temperature is high. The traditional compressor bleed air temperature is high and cannot fully meet the motor cooling and sealing requirements.

[0007] Third, the pivot sealing system of traditional aero engines is at risk of sealing failure due to insufficient sealing pressure differential under slow or lower speed conditions. It is usually equipped with an ejector device to increase the sealing pressure differential by reducing the pressure in the bearing cavity. However, in hybrid engines, it is difficult to install the ejector device. Therefore, the traditional bleed air solution cannot guarantee the sealing pressure differential under low operating conditions.

[0008] IV. Cooling of the motor and support sealing system If the aircraft's electro-environmental bleed air system is used to supply air, it will undoubtedly increase the size of the electro-environmental bleed air system, increase the difficulty of its layout, and increase the weight of the aircraft.

[0009] Based on this, the inventors of this application propose a hybrid power engine cooling system, cooling method, and hybrid power engine to solve the aforementioned technical problems. Summary of the Invention

[0010] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing hybrid engine cooling system, which cannot meet the cooling requirements of the motor and the pivot sealing system under different operating conditions, and to provide a hybrid engine cooling system, cooling method and hybrid engine.

[0011] The present invention solves the above-mentioned technical problems through the following technical solution:

[0012] This invention provides a hybrid engine cooling system, characterized in that it includes:

[0013] The first cooling flow path is connected at one end to the bleed air mechanism and is used to receive low-temperature cooling air from the outside of the cabin cover.

[0014] The second cooling flow path is connected to the compressor at one end and is used to receive the cooling sealing gas from the compressor side;

[0015] The other ends of the first and second cooling flow paths are connected to a third cooling flow path via control valves. The third cooling flow path is further divided into a first cooling branch and a second cooling branch. The first cooling branch is connected to the propulsion motor side, and the second cooling branch is connected to the fulcrum sealing system side.

[0016] When the prime mover is operating at a speed lower than the idle speed, the control valve controls the first cooling flow path to supply air to the propulsion motor and the pivot sealing system; when the prime mover is operating at a speed higher than the idle speed, the control valve controls the second cooling flow path to supply air to the propulsion motor and the pivot sealing system.

[0017] According to one embodiment of the present invention, the control valve is a three-way valve.

[0018] According to one embodiment of the present invention, a first regulating valve is provided on the first cooling branch to regulate the flow rate of cooling air delivered to the propulsion motor side;

[0019] A second regulating valve is provided on the second cooling branch to regulate the flow rate of cooling air delivered to the fulcrum sealing system side.

[0020] According to one embodiment of the present invention, a controller is further included, which is electrically connected to the control valve to control the connection between the first cooling flow path or the second cooling flow path and the third cooling flow path.

[0021] The present invention also proposes a hybrid power engine, comprising:

[0022] Compressor, propulsion motor, and hybrid engine cooling system as described above;

[0023] The hybrid engine cooling system is connected to both the compressor and the propulsion motor.

[0024] According to one embodiment of the present invention, it further includes a shroud, and the bleed air mechanism is installed inside the shroud;

[0025] The intake side of the bleed air mechanism extends to the outside of the hood, and the exhaust side of the bleed air mechanism is connected to the propulsion motor and the pivot sealing system via the control valve.

[0026] According to one embodiment of the present invention, it further includes a combustion chamber, a high-pressure turbine, a low-pressure turbine, and a tailpipe;

[0027] The compressor is located on one side of the combustion chamber, the propulsion motor is located at the tail nozzle, the first cooling flow path extends from the side near the inner wall of the hood to the side of the propulsion motor, and the second cooling flow path flows along the gap between the shaft and the combustion chamber, the high-pressure turbine and the low-pressure turbine to the pivot sealing system.

[0028] According to one embodiment of the present invention, an open rotor fan is also included, the open rotor fan being disposed on the side of the compressor away from the combustion chamber.

[0029] This invention proposes a cooling method for a hybrid power engine, implemented using the hybrid power engine cooling system described above. The cooling method includes:

[0030] Step 1: Obtain the operating status of the prime mover;

[0031] Step 2: Send a control signal to the control valve according to the operating status of the prime mover, so that the first cooling flow path or the second cooling flow path is connected to the first cooling branch and the second cooling branch.

[0032] According to one embodiment of the present invention, after step two, the method further includes:

[0033] Obtain the temperature values ​​on the propulsion motor side and / or the pivot sealing system side;

[0034] Adjust the opening degree of the first regulating valve and / or the second regulating valve according to the temperature value.

[0035] The positive and progressive effects of this invention are as follows:

[0036] The hybrid engine cooling system of this invention uses a control valve to connect a first cooling flow path and a second cooling flow path. When the prime mover is operating below idle speed, the control valve controls the first cooling flow path to supply air to the propulsion motor and the pivot sealing system. When the prime mover is operating above idle speed, the control valve controls the second cooling flow path to supply air to the propulsion motor and the pivot sealing system. This configuration allows the cooling system to cope with different operating conditions, reducing the risk of motor overheating and sealing failure, and also helps to reduce the design size of the bleed air mechanism, thereby reducing the weight of the engine. Attached Figure Description

[0037] The above and other features, properties and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, wherein:

[0038] Figure 1 This is a schematic diagram of the architecture of the hybrid engine cooling system of the present invention;

[0039] Figure 2 This is a simplified structural diagram of the hybrid power engine of the present invention;

[0040] Figure 3 This is a flowchart of the hybrid engine cooling method of the present invention.

[0041] 1. The first cooling flow path;

[0042] 2. Air intake mechanism;

[0043] 3. Cabin cover;

[0044] 4. Second cooling flow path;

[0045] 5. Air compressor;

[0046] 6. Control valve;

[0047] 7. Third cooling flow path; 71. First cooling branch; 72. Second cooling branch; 73. First regulating valve; 74. Second regulating valve;

[0048] 8. Propulsion motor;

[0049] 9. Controller;

[0050] 901. High-pressure turbine; 902. Low-pressure turbine; 903. Tail nozzle; 904. Open rotor fan; 905. Combustion chamber; 906. Pivot sealing system. Detailed Implementation

[0051] The present invention will be further described below with reference to specific embodiments and accompanying drawings. More details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention can obviously be implemented in many other ways different from those described herein. Those skilled in the art can make similar extensions and derivations based on actual application situations without departing from the spirit of the present invention. Therefore, the scope of protection of the present invention should not be limited by the content of this specific embodiment.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0053] Please refer to Figure 1 and Figure 2 This invention proposes a hybrid power engine cooling system, which includes a first cooling flow path 1 and a second cooling flow path 4. One end of the first cooling flow path 1 is connected to the bleed air mechanism 2 to receive low-temperature cooling air from the outside of the housing 3. One end of the second cooling flow path 4 is connected to the compressor 5 to receive cooling and sealing air from the compressor 5. The other ends of the first cooling flow path 1 and the second cooling flow path 4 are connected to a third cooling flow path 7 via a control valve 6. The third cooling flow path 7 is divided into a first cooling branch 71 and a second cooling branch 72. The first cooling branch 71 is connected to the propulsion motor 8, and the second cooling branch 72 is connected to the pivot sealing system 906.

[0054] When the prime mover is in a working state lower than the idle state, the control valve 6 controls the first cooling flow path 1 to supply air to the propulsion motor 8 and the pivot sealing system 906; when the prime mover is in a working state higher than the idle state, the control valve 6 controls the second cooling flow path 4 to supply air to the propulsion motor 8 and the pivot sealing system 906.

[0055] It is known that during engine operation, air needs to be continuously supplied to the motor cooling system and the pivot sealing system 906. This invention utilizes control valve 6 to supply air to the propulsion motor 8 and the pivot sealing system 906 via the bleed air mechanism 2 when the prime mover's operating state is lower than the idle state; and when the prime mover's operating state is higher than the idle state, the compressor 5 supplies air to the propulsion motor 8 and the pivot sealing system 906.

[0056] Based on this, the cooling gas distribution of the present invention takes into account different operating conditions of the engine. According to different operating conditions, the compressor 5 or the bleed air mechanism 2 is used to supply air to the propulsion motor 8 and the pivot sealing system 906, thereby avoiding the risk of overheating failure of the propulsion motor 8 and failure of the pivot sealing system 906.

[0057] Not only does it meet the temperature and pressure requirements of the 906 pivot sealing system, but it also uses compressor 5 to bleed air at high speeds, which reduces the bleed air flow of bleed air mechanism 2 and thus reduces the design size of bleed air mechanism 2, ultimately helping to meet the lightweight design requirements of the engine.

[0058] Specifically, in traditional engines, rotor jamming occurs due to heat re-soaking after shutdown. This invention uses a control valve 6 to continuously provide cooling air to the propulsion motor 8 and the pivot sealing system 906 through the bleed air mechanism 2 after shutdown, coordinating the deformation of the rotor and stator and increasing engine life.

[0059] In one implementation, control valve 6 is a three-way valve.

[0060] The control valve 6 can control the connection between the third cooling flow path 7 and the first cooling flow path 1 or the second cooling flow path 4, so as to control the supply of cooling air to the propulsion motor 8 and the pivot sealing system 906 via the bleed air mechanism 2 or the compressor 5.

[0061] For example, when the bleed pressure at the compressor 5 end is less than the outlet pressure of the bleed mechanism 2 and reaches the first target threshold, the first cooling flow path 1 and the third cooling flow path 7 are connected by the control valve 6.

[0062] When the bleed pressure of compressor 5 is greater than the outlet pressure of bleed mechanism 2 and reaches the second target threshold, the second cooling flow path 4 is connected to the fourth cooling flow path through control valve 6.

[0063] In one embodiment, the bleed air mechanism 2 can be an electrically controlled bleed air device.

[0064] Furthermore, a first regulating valve 73 is provided on the first cooling branch 71 to regulate the flow rate of cooling air delivered to the propulsion motor 8 side; a second regulating valve 74 is provided on the second cooling branch 72 to regulate the flow rate of cooling air delivered to the fulcrum sealing system 906 side.

[0065] A first regulating valve 73 is installed on the first cooling branch 71, thereby adjusting the flow rate of the cooling air delivered to the propulsion motor 8 via the bleed air mechanism 2 according to the temperature on the propulsion motor 8 side.

[0066] Similarly, a second regulating valve 74 is installed on the second cooling branch 72, thereby adjusting the flow rate of the cooling gas delivered to the fulcrum sealing system 906 via the compressor 5 according to the temperature on the fulcrum sealing system 906 side.

[0067] That is, a controller 9 is provided on the engine side. The controller 9 is electrically connected to the control valve 6. The controller 9 is used to control the connection between the first cooling flow path 1 or the second cooling flow path 4 and the third cooling flow path 7.

[0068] Furthermore, control valve 6 is also electrically connected to the first regulating valve 73 and the second regulating valve 74, thereby regulating the flow rate of coolant delivered to the propulsion motor 8 and the pivot sealing system 906 according to the temperature on the propulsion motor 8 side and the pivot sealing system 906 side.

[0069] The hybrid power engine cooling system proposed in this invention can provide cooling air with appropriate flow rate, pressure, and temperature based on the temperature values ​​at the propulsion motor 8 and the pivot sealing system 906. This satisfies the heat insulation requirements of the propulsion motor 8 and the temperature and pressure requirements of the pivot sealing system 906, and can remove the heat generated at the propulsion motor 8 and the pivot sealing system 906, ensuring the normal operation of the propulsion motor 8 and the pivot sealing system 906 under different operating conditions, thus improving the safety of the hybrid power engine. At the same time, it can continuously supply air to the propulsion motor 8 and the pivot sealing system 906 after the engine stops, improving the problem of heat recoil after the engine stops.

[0070] The present invention also proposes a hybrid power engine, comprising: a compressor 5, a propulsion motor 8, and a hybrid power engine cooling system as described above; the hybrid power engine cooling system is connected to the compressor 5 and the propulsion motor 8 respectively.

[0071] Specifically, it also includes a hood 3, with an air intake mechanism 2 installed inside the hood 3; the intake side of the air intake mechanism 2 extends to the outside of the hood 3, and the exhaust side of the air intake mechanism 2 is connected to the propulsion motor 8 and the pivot sealing system 906 via a control valve 6.

[0072] Furthermore, the engine also includes a combustion chamber 905, a high-pressure turbine 901, a low-pressure turbine 902, and a tail nozzle 903; the compressor 5 is located on one side of the combustion chamber 905, the propulsion motor 8 is located at the tail nozzle 903, the first cooling flow path 1 extends along the side near the inner wall of the shroud 3 to the side of the propulsion motor 8, and the second cooling flow path 4 flows along the gap between the rotating shaft and the combustion chamber 905, the high-pressure turbine 901, and the low-pressure turbine 902 to the pivot sealing system 906.

[0073] In one embodiment, the first cooling flow path 1 can be a pipe structure arranged on the inner wall side of the shroud 3 and extending to the propulsion motor 8 to provide cooling air to the propulsion motor 8.

[0074] The second cooling flow path 4 can be a gap flow channel between the rotating shaft and the combustion chamber 905, the high-pressure turbine 901 and the low-pressure turbine 902, so as to deliver the low-temperature cooling gas on the compressor 5 side to the pivot sealing system 906 position.

[0075] It can be seen that the arrangement of the first cooling flow path 1 is not limited to being arranged close to the inside of the housing 3. It can also be led to the outside of the housing 3 and introduced into the housing 3 from the outside of the housing 3 when it is close to the propulsion motor 8 and then led to the propulsion motor 8. Both methods are acceptable and are not limited here.

[0076] For the second cooling flow path 4, the second cooling flow path 4 can also adopt a pipe structure, arranged on one side of the shaft, and open at the fulcrum sealing system 906 position to deliver low temperature cooling gas to the fulcrum sealing system 906 position.

[0077] Alternatively, the cooling gas is drawn from the compressor 5, flows through the pipeline or the internal structure of the compressor 5 such as the disc cavity, shaft cavity, hole, and grate, and flows to the turbine end or the outer periphery of the engine bearing cavity to cool the turbine, prevent the parts from overheating, and seal the bearing cavity to prevent lubricating oil leakage. The cooled gas is finally discharged into the main stream or enters the bearing cavity.

[0078] The hybrid power engine proposed in this invention uses an open rotor fan 904 and a propulsion motor 8 as the hybrid power source. The open rotor fan 904 is located on the side of the compressor 5 away from the combustion chamber 905.

[0079] Please refer to Figure 3 The present invention also proposes a hybrid power engine cooling method, which is implemented using the hybrid power engine cooling system described above. The cooling method includes:

[0080] Step 1: Obtain the operating status of the prime mover;

[0081] Step 2: Send a control signal to the control valve according to the operating status of the prime mover, so that the first cooling flow path or the second cooling flow path is connected to the first cooling branch and the second cooling branch.

[0082] Furthermore, following step two, the following is also included:

[0083] Obtain temperature values ​​on the propulsion motor side and / or the pivot sealing system side;

[0084] Adjust the opening degree of the first regulating valve and / or the second regulating valve according to the temperature value.

[0085] That is, when the compressor end bleed pressure is less than the bleed mechanism outlet pressure and reaches the first target threshold, the first cooling flow path and the third cooling flow path are connected by the control valve.

[0086] When the compressor bleed air pressure is greater than the bleed air mechanism outlet pressure and reaches the second target threshold, the second cooling flow path and the fourth cooling flow path are connected by a control valve.

[0087] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation", "connection", "joining", and "fixing" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can also refer to mechanical connections. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0088] This application uses specific terms to describe embodiments of the application. Terms such as "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of the application. Therefore, it should be emphasized and noted that references to "an embodiment," "one embodiment," or "an alternative embodiment" in different locations throughout this specification do not necessarily refer to the same embodiment. Furthermore, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0089] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any variations and modifications can be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention, without departing from the scope of the invention, fall within the protection scope defined by the claims of the present invention.

Claims

1. A hybrid engine cooling system, characterized in that, include: The first cooling flow path is connected at one end to the bleed air mechanism and is used to receive low-temperature cooling air from the outside of the cabin cover. The second cooling flow path is connected to the compressor at one end and is used to receive the cooling sealing gas from the compressor side; The other ends of the first and second cooling flow paths are connected to a third cooling flow path via control valves. The third cooling flow path is further divided into a first cooling branch and a second cooling branch. The first cooling branch is connected to the propulsion motor side, and the second cooling branch is connected to the fulcrum sealing system side. When the prime mover is operating at a speed lower than the idle speed, the control valve controls the first cooling flow path to supply air to the propulsion motor and the pivot sealing system; when the prime mover is operating at a speed higher than the idle speed, the control valve controls the second cooling flow path to supply air to the propulsion motor and the pivot sealing system.

2. The hybrid engine cooling system according to claim 1, characterized in that, The control valve is a three-way valve.

3. The hybrid engine cooling system according to claim 1, characterized in that, A first regulating valve is provided on the first cooling branch to regulate the flow rate of cooling air delivered to the propulsion motor side; A second regulating valve is provided on the second cooling branch to regulate the flow rate of cooling air delivered to the fulcrum sealing system side.

4. The hybrid engine cooling system according to claim 1, characterized in that, It also includes a controller, which is electrically connected to the control valve to control the connection between the first cooling flow path or the second cooling flow path and the third cooling flow path.

5. A hybrid power engine, characterized in that, include: Compressor, propulsion motor, and hybrid engine cooling system as described in any one of claims 1-4; The hybrid engine cooling system is connected to both the compressor and the propulsion motor.

6. The hybrid power engine according to claim 5, characterized in that, It also includes a hood, inside which the bleed air mechanism is installed; The intake side of the bleed air mechanism extends to the outside of the hood, and the exhaust side of the bleed air mechanism is connected to the propulsion motor and the pivot sealing system via the control valve.

7. The hybrid power engine according to claim 5, characterized in that, It also includes the combustion chamber, high-pressure turbine, low-pressure turbine, and tailpipe; The compressor is located on one side of the combustion chamber, the propulsion motor is located at the tail nozzle, the first cooling flow path extends from the side near the inner wall of the hood to the side of the propulsion motor, and the second cooling flow path flows along the gap between the shaft and the combustion chamber, the high-pressure turbine and the low-pressure turbine to the pivot sealing system.

8. The hybrid power engine according to claim 7, characterized in that, It also includes an open rotor fan, which is located on the side of the compressor away from the combustion chamber.

9. A method for cooling a hybrid engine, characterized in that, The cooling method is achieved using a hybrid engine cooling system as described in any one of claims 1-4, wherein the cooling method comprises: Obtain the operating status of the prime mover; According to the operating state of the prime mover, a control signal is sent to the control valve to connect the first cooling flow path or the second cooling flow path with the first cooling branch and the second cooling branch.

10. The hybrid engine cooling method according to claim 9, characterized in that, Obtain the temperature values ​​on the propulsion motor side and / or the pivot sealing system side; Adjust the opening degree of the first regulating valve and / or the second regulating valve according to the temperature value.

Images