An oil supply system for a turbojet engine and a turbojet engine

Abstract

The present invention discloses an oil supply system and a turbojet engine for a turbojet engine, including an oil supply pipeline (1) and a centrifugal nozzle assembly (21). The centrifugal nozzle assembly (21) is located at the end of a combustion chamber (4). The oil supply pipeline (1) is arranged inside an engine housing (3), with one end communicating with a fuel tank and the other end communicating with the centrifugal nozzle assembly (21). The middle part of the oil supply pipeline (1) is spiral and sleeved outside the peripheral wall of the combustion chamber (4). The present invention improves the structure and installation position of the oil supply pipeline (1), combines the two methods of preheating atomization and centrifugal atomization, not only improves the fuel atomization effect, but also reduces the influence of the oil supply pipeline (1) on the installation size of the engine, avoids damage to the oil supply pipeline (1). At the same time, there is no need to set up an oil return circuit and a control system, reducing the complexity of the oil supply system.

Description

Technical Field

[0001] The present invention relates to the technical field of micro-aeroengines, and particularly to a fuel supply system for a turbojet engine and a turbojet engine. Background Art

[0002] Micro-turbojet engines have the characteristics of small size, light weight, simple structure, low cost, short life, and convenient maintenance and use, and are widely used in power devices for military aviation such as unmanned aerial vehicles and cruise missiles or civilian model aircraft.

[0003] In the prior art, low-cost and high-performance turbojet engines usually adopt an evaporation tube combustion chamber. However, due to its own design characteristics, there are problems such as poor atomization effect and difficult ignition. Summary of the Invention

[0004] The purpose of the present invention is to provide a fuel supply system for a turbojet engine, which while ensuring the atomization effect, reduces the influence of the fuel supply pipeline on the installation size of the engine, avoids damage to the fuel supply pipeline, and reduces the complexity of the fuel supply system.

[0005] Another purpose of the present invention is to provide a turbojet engine, which while ensuring the atomization effect, reduces the influence of the fuel supply pipeline on the installation size of the engine, avoids damage to the fuel supply pipeline, and reduces the complexity of the fuel supply system.

[0006] To solve the above technical problems, the present invention provides a fuel supply system for a turbojet engine, including a fuel supply pipeline and a centrifugal nozzle assembly. The centrifugal nozzle assembly is located at the end of the combustion chamber. The fuel supply pipeline is arranged inside the engine housing, one end is connected to the fuel tank, and the other end is connected to the centrifugal nozzle assembly. The middle part of the fuel supply pipeline is spiral and sleeved outside the peripheral wall of the combustion chamber.

[0007] For the fuel supply system of the turbojet engine of the present invention, the structure of the fuel supply pipeline is improved. The middle part of the fuel supply pipeline is set as spiral and sleeved outside the peripheral wall of the combustion chamber. In this way, the flow path of the fuel flowing through the fuel supply pipeline is extended to fully exchange heat with the combustion chamber, and the heat in the combustion chamber is used to preheat the fuel, so that the fuel is preliminarily atomized in the fuel supply pipeline. Then the fuel enters the centrifugal nozzle assembly, and is secondarily atomized through centrifugal action, and finally sprayed into the combustion chamber.

[0008] It can be seen that the fuel supply system of the turbojet engine of the present invention combines the two methods of preheating atomization and centrifugal atomization, which not only improves the atomization effect, but also arranges the fuel supply pipeline inside the engine housing, which can reduce the influence of the fuel supply pipeline on the installation size of the engine and avoid damage to the fuel supply pipeline.

[0009] Optionally, it further includes a mounting seat which is fixed to the end of the engine housing. An accommodating cavity evenly distributed circumferentially is arranged inside the mounting seat. The centrifugal nozzle assembly is sealed and installed on the mounting seat and corresponds to communicate with the accommodating cavity. An annular flow passage communicating with each accommodating cavity is further arranged inside the mounting seat, and the oil supply pipeline communicates with the annular flow passage.

[0010] Optionally, the number of the accommodating cavities is equal to that of the centrifugal nozzle assemblies and is more than eight.

[0011] Optionally, an oil inlet is further arranged at the radially outer end of the annular flow passage inside the mounting seat. The oil inlet communicates with the annular flow passage through an oil inlet passage, and the oil supply pipeline communicates with the oil inlet.

[0012] Optionally, the centrifugal nozzle assembly includes a shell part, a head part and a pressing part. The shell part is axially communicated.

[0013] A conical inner cavity is formed inside the head part. The pointed end of the conical inner cavity communicates with the fuel injection hole. A hole part extending tangentially is arranged on the peripheral wall of the head part to communicate the conical inner cavity. The head part is installed inside the shell part.

[0014] The pressing part is hermetically connected inside the shell part to press the head part and block the inner end of the conical inner cavity.

[0015] An oil inlet hole is arranged on the peripheral wall of the shell part. The shell part is hermetically installed on the mounting seat. The outer end of the oil inlet hole communicates with the accommodating cavity, and the inner end of the oil inlet hole communicates with the hole part through an annular gap between the pressing part and the shell part.

[0016] Optionally, the oil inlet hole includes an annular concave cavity. At least one hole body extending radially and communicating with the annular gap is arranged on the bottom wall of the annular concave cavity. Sealing rings are respectively installed at the two axial ends of the annular concave cavity on the outer peripheral wall of the shell part;

[0017] And / or, the number of the hole parts is 2 - 4 and is evenly distributed circumferentially.

[0018] Optionally, the inside of the shell part includes a first diameter section, a second diameter section and a third diameter section which are axially communicated. The diameters of the first diameter section, the second diameter section and the third diameter section increase in sequence. A first step surface is formed between the first diameter section and the second diameter section.

[0019] The outer periphery of the head includes a first connecting section and a second connecting section that are axially connected. The first connecting section cooperates with the first diameter section, and a part of the second connecting section cooperates with the second diameter section. A second step surface is formed between the first connecting section and the second connecting section, and the second step surface abuts against the first step surface. The pressing portion presses the inner end of the second connecting section.

[0020] Optionally, the pressing portion includes a third connecting section and a fourth connecting section that are axially connected. The diameter of the fourth connecting section is larger than that of the third connecting section. The fourth connecting section is hermetically connected to the housing portion by a thread. The third connecting section presses the head, and an annular gap is formed between the third connecting section and the third diameter section. The oil inlet hole is provided at the connection of the third connecting section and the fourth connecting section.

[0021] Optionally, a fastening notch is provided at one end of the pressing portion away from the head.

[0022] The present invention also provides a turbojet engine, including the fuel supply system of the aforementioned turbojet engine.

[0023] The turbojet engine of the present invention includes the fuel supply system of the aforementioned turbojet engine, and thus has the same technical effects as the fuel supply system of the aforementioned turbojet engine, which will not be elaborated here. Description of the Drawings

[0024] Figure 1 It is a schematic structural diagram of a specific embodiment of the turbojet engine provided by the present invention;

[0025] Figure 2 is Figure 1 a schematic structural diagram of the fuel supply system in

[0026] Figure 3 is Figure 2 a cross-sectional view of the inside of the mounting seat in

[0027] Figure 4 is Figure 2 an axial cross-sectional view of the centrifugal nozzle assembly in

[0028] Figure 5 is Figure 4 a schematic diagram of the head in the centrifugal nozzle assembly;

[0029] Among them, Figures 1-5 the reference numerals in

[0030] 1 - fuel supply pipeline;

[0031] 21 - centrifugal nozzle assembly; 211 - housing portion; 211a - oil inlet hole; 212 - head; 212a - tapered inner cavity;

[0032] 212b - fuel injection hole; 212c - hole part; 213 - pressing part; 213a - fastening notch; 214 - sealing ring; 22 - mounting seat; 22a - accommodating cavity; 22b - annular flow channel; 22c - oil inlet; 22d - oil inlet channel;

[0033] 3 - engine housing;

[0034] 4 - combustion chamber;

[0035] 5 - air inlet duct. Specific embodiments

[0036] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] The terms "first", "second", etc. described herein are only for the convenience of describing two or more structures or components with the same or similar structures and / or functions, and do not represent a certain special limitation on the order and / or importance.

[0038] Please refer to Figures 1-2 , Figure 1 which is a schematic structural diagram of a specific embodiment of the turbojet engine provided by the present invention; Figure 2 is Figure 1 a schematic structural diagram of the fuel supply system in

[0039] The present invention provides a fuel supply system for a turbojet engine, including a fuel supply pipeline 1 and a centrifugal nozzle assembly 21. The centrifugal nozzle assembly 21 is located at the end of the combustion chamber 4. The fuel supply pipeline 1 is arranged inside the engine housing 3, one end is communicated with the fuel tank, the other end is communicated with the centrifugal nozzle assembly 21, and the middle part of the fuel supply pipeline 1 is spiral and sleeved outside the peripheral wall of the combustion chamber 4.

[0040] The fuel supply system of the turbojet engine of the present invention improves the preheating method of fuel. First, the middle part of the fuel supply pipeline 1 is set to be spiral and sleeved outside the peripheral wall of the combustion chamber 4. In this way, the flow path of the fuel flowing through the fuel supply pipeline 1 is extended to fully exchange heat with the combustion chamber 4, and the heat in the combustion chamber 4 is used to preheat the fuel, so that the fuel is preliminarily atomized in the fuel supply pipeline 1. Then the fuel enters the inside of the centrifugal nozzle assembly 21 and is secondarily atomized under the action of centrifugal force, and finally sprayed into the combustion chamber 4.

[0041] It can be seen from this that the fuel supply system of the turbojet engine of the present invention combines the two methods of preheating atomization and centrifugal atomization, which not only improves the atomization effect, but also arranges the fuel supply pipeline 1 inside the engine housing 3, which can reduce the influence of the fuel supply pipeline 1 on the installation size of the engine, avoid damage to the fuel supply pipeline 1, and reduce the complexity of the fuel supply system.

[0042] In practical applications, the pitch of the spiral structure in the middle of the fuel supply pipeline 1 can be determined according to the diameter of the fuel supply pipeline 1 and the axial distance of the combustion chamber 4.

[0043] Please refer to Figures 1-3 , Figure 3 is Figure 2 the internal sectional view of the mounting seat.

[0044] The fuel supply system of the turbojet engine of the present invention further includes a mounting seat 22, and the mounting seat 22 is fixed to one end of the engine housing 3. As Figure 1 can be seen, the mounting seat 22 is specifically located at one end of the opening of the combustion chamber 4. The other end of the engine housing 3 is communicated with the air inlet duct 5. Twelve receiving cavities 22a are arranged inside the mounting seat 22, and the twelve receiving cavities 22a are evenly distributed along the circumferential direction of the mounting seat 22. The centrifugal nozzle assembly 21 is hermetically installed on the mounting seat 22 and is communicated with the receiving cavities 22a one by one. An annular flow passage 22b communicating with each receiving cavity 22a is arranged inside the mounting seat 22. An oil inlet 22c is further arranged at the radially outer end of the annular flow passage 22b on the inner side of the mounting seat 22. The oil inlet 22c is communicated with the annular flow passage 22b through an oil inlet passage 22d. The corresponding end of the fuel supply pipeline 1 is inserted into the inside of the oil inlet 22c and is communicated with the oil inlet 22c.

[0045] In this way, the fuel preheated by the fuel supply pipeline 1 will sequentially enter the inside of the annular flow passage 22b through the oil inlet 22c and the oil inlet passage 22d, and then be distributed to each receiving cavity 22a through the annular flow passage 22b. The fuel enters the corresponding centrifugal nozzle assembly 21 from the receiving cavity 22a. The fuel is further centrifugally atomized inside the centrifugal nozzle assembly 21 and then axially sprayed inside the combustion chamber 4.

[0046] It should be noted that the "inner side of the mounting seat 22" mentioned here refers to the side of the mounting seat 22 facing the combustion chamber 4.

[0047] By providing the mounting seat 22, on the one hand, the present invention plays a role in fixing each centrifugal nozzle assembly 21. On the other hand, by providing the annular flow passage 22b to connect the circumferential centrifugal nozzle assemblies 21, the structure is not only simple, but also ensures that the fuel entering the combustion chamber 4 is more uniform. In practical applications, in order to ensure the fuel uniformity, the number of the receiving cavities 22a should be at least eight or more. In addition, the mounting seat 22 is fixed to one end of the engine housing 3, and the fuel is axially sprayed inside the combustion chamber 4, so that the contact area between the fuel and the air is the largest, and then the two are fully mixed to improve the combustion efficiency.

[0048] In practical applications, the position of the oil inlet 22c is not limited. For example, the oil inlet 22c can also be located on the circumference where the annular flow passage 22b is located, and the radially inner end of the oil inlet passage 22d can also be communicated with the annular flow passage 22b.

[0049] Please refer to Figures 4-5 , Figure 4 the Figure 2 axial sectional view of the centrifugal nozzle assembly in Figure 5 and Figure 4 the schematic diagram of the head in the centrifugal nozzle assembly.

[0050] The centrifugal nozzle assembly 21 of the present invention specifically includes a shell part 211, a head 212 and a pressing part 213. The shell part 211 is axially connected. Its interior includes a first diameter section, a second diameter section and a third diameter section that are axially connected. The diameters of the first diameter section, the second diameter section and the third diameter section increase in sequence. A first step surface is formed between the first diameter section and the second diameter section.

[0051] The outer periphery of the head 212 includes an axially connected first connection section and a second connection section. When the head 212 is installed in the shell part 211, the first connection section cooperates with the first diameter section, and part of the second connection section cooperates with the second diameter section. A second step surface is formed between the first connection section and the second connection section. The second step surface abuts against the first step surface, making the installation of the head 212 in the shell part 211 more stable. A conical inner cavity 212a is formed inside the head 212. The pointed end of the conical inner cavity 212a communicates with the fuel injection hole 212b. The peripheral wall of the head 212 is provided with a hole part 212c extending tangentially. The hole part 212c communicates with the conical inner cavity 212a.

[0052] The pressing part 213 includes an axially connected third connection section and a fourth connection section. The diameter of the fourth connection section is greater than that of the third connection section. The pressing part 213 is also installed in the shell part 211. The fourth connection section is hermetically connected to the shell part 211 by threads. The end of the third connection section presses the head 212 and blocks the large diameter end of the conical inner cavity 212a to prevent fuel from entering the inside of the conical inner cavity 212a from the large diameter end. An annular gap is formed between the third connection section and the third diameter section.

[0053] The peripheral wall of the shell part 211 is provided with an oil inlet hole 211a. The oil inlet hole 211a is located at the connection of the third connection section and the fourth connection section. It specifically includes an annular cavity and at least one hole body extending radially and communicating with the aforementioned annular gap. Sealing grooves are respectively arranged on the outer peripheral wall of the shell part 211 on both axial sides of the annular cavity. Sealing rings 214 are installed inside the sealing grooves. When the shell part 211 is installed on the mounting seat 22, the outer end of the oil inlet hole 211a communicates with the accommodating cavity 22a. The sealing rings 214 on both sides ensure the sealing performance when the shell part 211 is installed on the mounting seat 22, so that fuel can only enter the inside of the oil inlet hole 211a. The inner end of the oil inlet hole 211a communicates with the hole part 212c through the aforementioned annular gap.

[0054] In this way, fuel with a certain pressure enters the housing part 211 from the fuel inlet hole 211a, then flows along the annular gap between the third connecting section and the third diameter section, and enters the inside of the conical inner cavity 212a from the hole part 212c on the peripheral wall of the head part 212. Since the hole part 212c extends tangentially along the head part 212, the pressure energy of the fuel is converted into velocity energy, generating high-speed rotation inside the conical inner cavity 212a, while moving towards the fuel injection hole 212b, strongly rubbing against the inner wall of the conical inner cavity 212a to further atomize, and finally spraying out from the fuel injection hole 212b.

[0055] Thus, the fuel supply system of the turbojet engine of the present invention performs secondary atomization on the fuel through the centrifugal nozzle assembly 21, improving the atomization effect of the fuel, thereby improving the combustion efficiency, and the centrifugal nozzle assembly 21 has a simple structure and is convenient for installation.

[0056] Among them, the number of the hole parts 212c can be 2 - 4, and they are evenly arranged along the circumferential direction. One end of the pressing part 213 away from the head part 212 is also provided with a fastening notch 213a, which can specifically be an internal hexagonal notch, a cross notch, etc., for torque tightening.

[0057] In practical applications, in addition to the pressing part 213 being hermetically connected to the housing part 211 through threads, at least one sealing ring can also be provided on the peripheral wall of the pressing part 213, and the sealing installation of the pressing part 213 and the housing part 211 is achieved by extruding the sealing ring.

[0058] In addition, the internal shape of the housing part 211 is not limited to the above settings. For example, the inside of the housing part 211 can only include a first diameter section and a second diameter section that are axially connected. The diameter of the first diameter section is smaller than that of the second diameter section, and a first step surface is formed between the first diameter section and the second diameter section for abutting against the second step surface on the outer periphery of the head part 212. The second connecting section and the pressing part 213 of the head part 212 are both installed inside the second diameter section, and an annular gap is also formed between the second connecting section and the second diameter section.

[0059] The present invention also provides a turbojet engine, including the fuel supply system of the aforementioned turbojet engine.

[0060] The turbojet engine of the present invention includes the fuel supply system of the aforementioned turbojet engine, and thus has the same technical effects as the fuel supply system of the aforementioned turbojet engine, which will not be elaborated here.

[0061] It should be understood that the structures of existing turbojet engines all include an air inlet duct 5, a compressor, a combustion chamber 4, a turbine, and a tail pipe. These are the main components of the engine, and their specific structures and specific connection relationships will not be elaborated here.

[0062] The above has introduced in detail a fuel supply system and a turbojet engine provided by the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A fuel supply system for a turbojet engine, characterized in that, It includes an oil supply pipeline (1) and a centrifugal nozzle assembly (21). The centrifugal nozzle assembly (21) is located at the end of the combustion chamber (4). The oil supply pipeline (1) is arranged inside the engine housing (3), with one end communicating with the fuel tank and the other end communicating with the centrifugal nozzle assembly (21). The middle part of the oil supply pipeline (1) is spiral and sleeved outside the circumferential wall of the combustion chamber (4). It further includes a mounting seat (22). The mounting seat (22) is fixed to one end of the engine housing (3). Inside the mounting seat (22), there are accommodation cavities (22a) evenly distributed along the circumferential direction. The centrifugal nozzle assembly (21) is sealed and installed in the mounting seat (22) and communicates with the accommodation cavities (22a) one by one. An annular flow channel (22b) communicating with each of the accommodation cavities (22a) is further arranged inside the mounting seat (22). The oil supply pipeline (1) communicates with the annular flow channel (22b).

2. The fuel supply system of the turbojet engine according to claim 1, wherein The number of the accommodation cavities (22a) and the centrifugal nozzle assembly (21) is more than eight.

3. The fuel supply system of the turbojet engine according to claim 1, characterized in that, An oil inlet (22c) is further arranged at the radially outer end of the annular flow channel (22b) inside the mounting seat (22). The oil inlet (22c) communicates with the annular flow channel (22b) through an oil inlet channel (22d). The oil supply pipeline (1) communicates with the oil inlet (22c).

4. The fuel supply system of the turbojet engine according to any one of claims 1-3, characterized in that The centrifugal nozzle assembly (21) includes a shell part (211), a head part (212) and a pressing part (213). The shell part (211) is axially communicated. A conical inner cavity (212a) is formed inside the head part (212). The pointed end of the conical inner cavity (212a) communicates with an injection hole (212b). A hole part (212c) extending tangentially is arranged on the circumferential wall of the head part (212). The hole part (212c) communicates with the conical inner cavity (212a). The head part (212) is installed inside the shell part (211). The pressing part (213) is sealed and installed inside the shell part (211) to press the head part (212) and block the large-diameter end of the conical inner cavity (212a). An oil inlet hole (211a) is arranged on the circumferential wall of the shell part (211). The shell part (211) is sealed and installed in the mounting seat (22). The outer end of the oil inlet hole (211a) communicates with the accommodation cavity (22a). The inner end of the oil inlet hole (211a) communicates with the hole part (212c) through an annular gap between the pressing part (213) and the shell part (211).

5. The fuel supply system of the turbojet engine according to claim 4, characterized in that, The oil inlet hole (211a) includes an annular concave cavity. At least one hole body extending radially and communicating with the annular gap is arranged on the bottom wall of the annular concave cavity. Sealing rings (214) are respectively installed on the outer circumferential wall of the shell part (211) on both axial sides of the annular concave cavity. And / or, the number of the hole parts (212c) is 2 - 4 and they are evenly distributed along the circumferential direction.

6. The fuel supply system of the turbojet engine according to claim 4, characterized in that, The interior of the shell portion (211) includes a first diameter section, a second diameter section, and a third diameter section that are axially connected. The diameters of the first diameter section, the second diameter section, and the third diameter section increase in sequence. A first step surface is formed between the first diameter section and the second diameter section. The outer periphery of the head portion (212) includes a first connection section and a second connection section that are axially connected. The first connection section is fitted with the first diameter section, and a part of the second connection section is fitted with the second diameter section. A second step surface is formed between the first connection section and the second connection section, and the second step surface abuts against the first step surface.

7. The fuel supply system of the turbojet engine according to claim 6, characterized in that, The pressing portion (213) includes a third connection section and a fourth connection section that are axially connected. The diameter of the fourth connection section is larger than that of the third connection section. The fourth connection section is in threaded sealing connection with the shell portion (211). The end of the third connection section presses the head portion (212). An annular gap is formed between the third connection section and the third diameter section. The oil inlet hole (211a) is provided at the connection between the third connection section and the fourth connection section.

8. The fuel supply system of the turbojet engine according to claim 4, characterized in that, A fastening notch (213a) is provided at one end of the pressing portion (213) away from the head portion (212).

9. A turbojet engine, characterized in that, It includes the fuel supply system of the turbojet engine according to any one of claims 1-8.

Images