CN108590859B

CN108590859B - Additive manufacturing's miniature turbojet engine

Info

Publication number: CN108590859B
Application number: CN201810371530.5A
Authority: CN
Inventors: 韩品连; 张坤
Original assignee: Shenzhen Yidong Aviation Technology Co Ltd
Current assignee: Shenzhen Yidong Aviation Technology Co Ltd
Priority date: 2018-04-24
Filing date: 2018-04-24
Publication date: 2021-03-09
Anticipated expiration: 2038-04-24
Also published as: CN108590859A

Abstract

The invention discloses a micro turbojet engine. The micro turbojet engine comprises a casing and a radial diffuser connected with the head of the casing, wherein the radial diffuser and the casing are integrally manufactured by an additive manufacturing technology. The casing and the radial diffuser are integrally manufactured by an additive manufacturing technology, so that the processing is convenient, the weight is reduced, and the processing and maintenance cost and difficulty are reduced.

Description

Additive manufacturing's miniature turbojet engine

Technical Field

The invention relates to the technical field of aero-engines, in particular to a micro turbojet engine with additive design and manufacturing.

Background

The micro turbojet has a plurality of components and a complex component supporting and connecting structure. The design and manufacturing process of the components in the prior art micro turbojet engines are complex.

Disclosure of Invention

The embodiment of the invention provides a micro turbojet engine manufactured by additive design.

The micro turbojet engine comprises a casing and a radial diffuser connected with the head of the casing, wherein the radial diffuser and the casing are integrally manufactured by an additive manufacturing technology.

The casing and the radial diffuser are integrally manufactured by the additive manufacturing technology, so that the supporting and connecting structures among all parts are reduced, the processing is convenient, the weight is reduced, and the processing and maintenance cost and difficulty are reduced.

In some embodiments, the case includes a case sidewall and a web stiffener extending from an inner surface of the case sidewall.

In certain embodiments, the casing further comprises a retainer extending from an inner surface of the casing sidewall, and the micro-turbojet engine further comprises a combustion assembly disposed within the casing, the retainer being configured to retain the combustion assembly.

In certain embodiments, the radial diffuser includes a diffuser portion and a connection portion that are integrally formed by additive manufacturing techniques.

In some embodiments, the diffuser includes a diffuser top wall, an inner cylinder wall extending from the diffuser top wall, and an outer cylinder wall extending from the diffuser top wall and surrounding the inner cylinder wall, a receiving space is formed between the inner cylinder wall and the outer cylinder wall, and the diffuser further includes a plurality of blades extending from the diffuser top wall and received in the receiving space, and the blades are configured to limit a flow direction of the airflow.

In some embodiments, the connection portion extends from the outer cylinder wall, the connection portion includes an installation column extending from an inner side wall, the installation column includes an installation section and a reinforcement section, an installation hole is opened at one end of the casing connected to the radial diffuser, and the micro turbojet engine further includes a connection member, and the connection member is inserted through the installation hole and the installation section to connect the radial diffuser and the casing.

In some embodiments, the miniature turbojet engine further comprises a motor support and a motor, the motor support comprises a first installation part and a second installation part, when the first installation part is combined with the second installation part, an accommodating cavity is formed between the first installation part and the second installation part, the motor is accommodated in the accommodating cavity, and the first installation part and the second installation part are integrally formed through an additive manufacturing technology.

In some embodiments, the miniature turbojet engine further comprises an air inlet channel, one end of the air inlet channel is connected with the motor support, the other end of the air inlet channel is connected with the diffusion part, the miniature turbojet engine further comprises a gas compressor, and the gas compressor is connected with the motor and penetrates through the air inlet channel.

In some embodiments, the micro turbojet engine further comprises a jet nozzle fixedly connected to the other end of the casing, the jet nozzle being integrally formed by an additive manufacturing technique.

In some embodiments, a first flange is formed at a tail portion of the casing, the first flange is provided with a plurality of first fixing holes, a second flange matched with the first flange is formed at one end of the jet pipe connected with the casing, the second flange is provided with a plurality of second fixing holes, and the connecting piece penetrates through the second fixing holes and the first fixing holes to fixedly connect the jet pipe with the casing.

Additional aspects and advantages of embodiments of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of embodiments of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic structural view of a micro turbojet engine according to an embodiment of the present invention;

FIG. 2 is a schematic plan view of a micro turbojet engine according to an embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view of the micro turbojet engine of FIG. 2 taken along line III-III;

FIG. 4 is a schematic perspective view of a motor mount in a micro turbojet engine according to an embodiment of the present invention;

FIG. 5 is a perspective view of a second mounting portion of a motor mount according to an embodiment of the present invention;

FIG. 6 is a schematic perspective view of an air intake duct in a micro turbojet engine according to an embodiment of the present invention;

FIG. 7 is a schematic cross-sectional view of the inlet of FIG. 6 taken along line VII-VII;

FIG. 8 is a schematic perspective view of a radial diffuser in a micro turbojet engine according to an embodiment of the present invention

FIG. 9 is a perspective view of another view of a radial diffuser according to an embodiment of the present invention;

FIG. 10 is a schematic perspective view of a case in a micro turbojet engine according to an embodiment of the present invention;

FIG. 11 is a perspective view of another perspective view of a receiver according to an embodiment of the present invention;

FIG. 12 is a schematic perspective view of a jet nozzle in a micro turbojet engine according to an embodiment of the present invention;

FIG. 13 is a schematic cross-sectional view of the jet nozzle of FIG. 12 taken along line XIII-XIII;

FIG. 14 is a schematic perspective view of a combustion assembly in a micro-turbojet engine in accordance with an embodiment of the invention;

FIG. 15 is a schematic structural view of the combustion assembly of FIG. 9;

FIG. 16 is a partial schematic structural view of a combustion assembly according to an embodiment of the invention;

FIG. 17 is a schematic plan view of a combustion assembly according to an embodiment of the invention;

FIG. 18 is a schematic plan view of a combustion assembly according to an embodiment of the invention;

FIG. 19 is a perspective view of a combustion assembly in accordance with an embodiment of the present invention;

FIG. 20 is a schematic structural view of the combustion assembly of FIG. 14;

FIG. 21 is a schematic structural view of a two-stage flame tube according to an embodiment of the invention;

FIG. 22 is a schematic structural view of a first section of a liner according to an embodiment of the present invention;

FIG. 23 is a schematic structural view of a second section of the liner according to an embodiment of the present invention; and

fig. 24 is a partial structural view of a combustor basket according to an embodiment of the present invention.

Description of the main element symbols:

a micro turbojet engine 1000; the combustion assembly 100, the inlet duct 200, the diffuser assembly 300, the casing 400, the exhaust nozzle 500, the motor assembly 600, the turbine 700, the rotor assembly 800 and the connecting piece 900; the flame tube 10, the main body 11, the through hole 110, the combustion chamber 111, the head 1111, the tail 1112, the first hole 112, the second hole 113, the inner tube 114, the base 1141, the mounting hole 1142, the outer tube 115, the inner cavity 116, the outer ring cavity 117, the baffle 118, the third hole 119, the first section 12, the first opening 121, the groove 122, the positioning block 123, the second section 13, the second opening 131 and the protrusion 132; the nozzle 20, the nozzle side wall 21, the spiral pipe 22, the injection hole 221, the nozzle inlet 23, the nozzle outlet 24, the nozzle top wall 25, the nozzle bottom wall 26 and the oil injection cavity 27; the turbine guide vane 30, the first connecting end 31, the second connecting end 32 and the air film hole 33; fuel piping 40, main pipe 41, distribution chamber 42, branch pipe 43; a second through hole 210, a first connection hole 220; the compressor 310, the radial diffuser 320, the diffuser 322, the diffuser top wall 3221, the inner cylinder wall 3222, the outer cylinder wall 3223, the blades 3224, the accommodating space 3225, the second connecting hole 3226, the connecting part 324, the inner side wall 3241, the mounting column 3242, the mounting section 3243 and the reinforcing section 3244; casing side wall 410, web reinforcement 420, retaining member 430, mounting hole 440, head 450, first end face 460, first fixing hole 462, fastener 464, tail 470. Side wall 510, flange 520, second end surface 522, second securing aperture 524; the motor comprises a motor bracket 610, a first mounting part 612, a second mounting part 614, a first through hole 616, a containing cavity 618 and a motor 620; a bucket 710; rotor support 810, axle sleeve 812, axial diffuser 814, lateral wall 8142, axial diffuser blade 8144, connecting shaft 820.

Detailed Description

The following further describes embodiments of the present invention with reference to the drawings. The same or similar reference numbers in the drawings identify the same or similar elements or elements having the same or similar functionality throughout.

In addition, the embodiments of the present invention described below with reference to the accompanying drawings are exemplary only for the purpose of explaining the embodiments of the present invention, and are not to be construed as limiting the present invention.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

The micro turbojet engine of the related art has a plurality of components, and the connection structure between the components is complex, such as: the structure for connecting the diffuser and the casing needs the diffuser, the connecting part and the casing, the connecting structure such as a combination hole needs to be arranged on the diffuser, other processes are needed for processing and drilling, meanwhile, the connecting part is arranged on the connecting structure matched with the connecting structure of the diffuser, and after the diffuser and the connecting part are connected, the connecting part and the casing are connected by using a similar method, so that the structure is complex, the connecting structure is numerous, the processing procedures are more, and the combination strength is common. Therefore, the invention provides a micro turbojet engine manufactured based on additive design.

Referring to fig. 1 to 3, a micro turbojet engine 1000 according to an embodiment of the present invention includes a combustion assembly 100, an intake duct 200, a diffuser assembly 300, a casing 400, a nozzle 500, a motor assembly 600, a turbine 700, a rotor assembly 800, and a plurality of connectors 900. The micro turbojet engine 1000 may be an engine of an unmanned aerial vehicle or an engine of an automotive power system, or the like.

The motor assembly 600 is connected to one end of the intake duct 200, the diffuser assembly 300 is connected to the other end of the intake duct 200, the diffuser assembly 300 is connected to the head portion 450 of the casing 400, the tail nozzle 500 is connected to the tail portion 470 of the casing 400, and the combustion assembly 100, the turbine 700, and the connecting shaft 820 are disposed in the casing 400. One end of the rotor assembly 800 is connected to the diffuser assembly 300, and the other end of the rotor assembly 800 penetrates the combustion assembly 100 and is connected to the turbine 700.

Referring to fig. 2 to 5, the motor assembly 600 includes a motor 620 and a motor support 610. The motor bracket comprises a first mounting part 612, a second mounting part 614 and at least two first through holes 616, when the first mounting part 612 is combined with the second mounting part 614, a containing cavity 618 is formed between the first mounting part 612 and the second mounting part 614, and the motor 12 is contained in the containing cavity 618. The first mounting portion 612 and the second mounting portion 614 are integrally formed by an additive manufacturing technology, and the first through hole 616 is formed without using other processes for forming holes.

Referring to fig. 1, 2, 3, 6 and 7, the top surface of the air inlet duct 200 is provided with at least two second through holes 210 and a plurality of first connection holes 220, which are matched with the first through holes 616, and when the motor bracket 610 is combined with the air inlet duct 200, the connection member 900 penetrates through the first through holes 616 and the second through holes 210 to fixedly connect the motor bracket 610 with the air inlet duct 200. In other embodiments, the first and

second perforations

616, 210 may be greater than two, e.g., the first and

second perforations

616, 210 may be three, four, etc. in number. Thus, the motor bracket 610 is more firmly connected with the air inlet duct 200. The number of the first and second through

holes

616 and 210 of the embodiment of the present invention is two. The air inlet 200 is integrally formed by additive manufacturing technology without forming the second through hole 210 and the first connection hole 220 by using other processes. The connector 900 may be a screw, bolt, etc.

Referring to fig. 1, 2, 3, 8 and 9, the diffuser assembly 300 is disposed near the head of the combustion assembly 100. The diffuser assembly 300 includes a compressor 310 and a radial diffuser 320. The compressor 310 penetrates the air inlet channel 200 and is connected with the motor 620, and the compressor 310 is used for sucking air from the air inlet channel 200. The compressor 310 is connected with the radial diffuser 320 to form a narrow passage, and the gas outside the micro turbojet engine 1000 is sucked by the compressor 310 and accelerated in the process of passing through the narrow passage. The radial diffuser 320 serves to reduce the velocity of the gas to increase the pressure of the gas. The radial diffuser 320 forces the gases into the combustion assembly 100. The radial diffuser 320 includes a diffuser portion 322 and a connection portion 324. The diffuser 322 includes a diffuser top wall 3221, an inner cylinder wall 3222 extending from the diffuser top wall 3221, an outer cylinder wall 3223 extending from the diffuser top wall 3221 and surrounding the inner cylinder wall 3222, and a plurality of blades 3224 extending from the diffuser top wall 3221, wherein an accommodating space 3225 is formed between the inner cylinder wall 3222 and the outer cylinder wall 3223, and the plurality of blades 3224 are accommodated in the accommodating space 3225 and are used for limiting the flow of the gas flow to reduce the velocity of the gas and thereby increase the pressure of the gas. The diffuser top wall 3221 is provided with a plurality of second connection holes 3226 matching with the first connection holes 220, the second connection holes 3226 penetrate through the diffuser top wall 3221 and the plurality of blades 3224 extending from the diffuser top wall 3221, and when the intake duct 200 is connected with the radial diffuser 320, the connecting member 900 penetrates through the first connection holes 220 and the second connection holes 3226 to firmly connect the intake duct 200 and the radial diffuser 320 together. Connecting portion 324 extends from the top of outer barrel wall 3223, and connecting portion 324 includes the erection column 3242 that extends from inside wall 3241, and erection column 3242 includes erection section 3243 and reinforcement section 3244, and erection section 3243 is the cylinder structure that extends from inside wall 3241, and the through-hole has been seted up to the cylinder structure, and this through-hole runs through the lateral wall of connecting portion 324 and this cylinder structure, and reinforcement section 3244 is the wedge structure of the lateral wall of support cylinder structure for play reinforced effect to this cylinder structure. The diffuser portion 322 and the connection portion 324 of the radial diffuser 320 are integrated into a whole and are integrally formed through an additive manufacturing technology, and the casing can be connected through the connection portion 324 without an extra connection component.

Referring to fig. 1, 3, 10 and 11, the casing 400 includes a casing sidewall 410, a web reinforcement member 420 extending from an inner surface 402 of the casing sidewall 410, a limiting member 430 extending from the inner surface 402 of the casing sidewall 410, and a first end surface 460 disposed at an end portion 470 of the casing sidewall 410. The mesh reinforcement member 420 serves to reinforce the strength of the barrel 400, and the position limiting member 430 serves to limit the position of the combustion assembly 100. The head 450 of the casing sidewall 410 defines a plurality of mounting holes 440. When the connection portion 324 is connected to the head portion 450 of the casing 400, the head portion 450 of the casing 400 surrounds the side wall of the connection portion 324 (i.e., the connection portion 324 extends into the casing side wall 410), and the connection member 900 penetrates through the mounting hole 440 and the mounting section 3243 in sequence to firmly connect the radial diffuser 320 and the casing 400 together. The first end surface 460 defines a plurality of first fastening holes 462, the first end surface 460 further defines fastening members 464 extending from the first end surface 460 toward the diffuser assembly 300, and the first fastening holes 462 extend through the first end surface 460 and the fastening members 464. In other embodiments, the number of the limiting members 430 may be more than one. For example, the number of the limiting members 430 is two or three, and so on. Preferably, the number of the limiting members 430 is three, the limiting members 430 enclose a circle, and an included angle between each adjacent limiting member 430 and the center of the circle is 120 °, so that the combustion assembly 100 can be limited, the distance between the side wall of the combustion assembly 100 and the side wall 410 of the casing is equal, and the casing 400 is uniformly stressed. Of course, the number of the position-limiting members 430 may be more than four, so that the position limitation of the combustion assembly 100 is more stable. The number of the stoppers 430 according to the embodiment of the present invention is three. The casing side wall 410, the net-shaped reinforcing member 420, the limiting member 430, the mounting hole 440, the first end surface 460, the first fixing hole 462 and the fastening member 464 are integrated into a whole and are integrally formed through an additive manufacturing technology, and an extra mounting structure is not needed.

Referring to fig. 1, 3, 12 and 13, a flange 520 extending from a sidewall 510 of the jet nozzle 500 is formed at one end of the jet nozzle 500 connected to the casing 400, the flange 520 includes a second end surface 522 matched with the first end surface 460, the second end surface 522 is provided with a plurality of second fixing holes 524 matched with the plurality of first fixing holes 462, and the connecting member 900 penetrates through the second fixing holes 524 and the first fixing holes 462 to fixedly connect the jet nozzle 500 to the casing 400. Wherein, all parts on the exhaust nozzle 500 are integrated into a whole and are integrally formed by an additive manufacturing technology.

With continued reference to fig. 1 and 3, the combustion assembly 100 is disposed between the diffuser assembly 300 and the turbine 700. Diffuser assembly 300 is used to input high pressure gas to combustion assembly 100, and fuel and high pressure gas are mixed and combusted in combustion assembly 100 to convert chemical energy in the fuel into heat energy in the high temperature gas.

Turbine 700 is disposed near an aft portion of combustion assembly 100. The turbine 700 includes buckets 710. The turbine 700 is used to convert thermal energy of the high temperature gases flowing from the combustion assembly 100 into mechanical energy. Specifically, the high temperature and high pressure gas discharged from the combustion assembly 100 impinges upon the blades 710 of the turbine 700, causing the blades 710 to rotate. The turbine 700 is integrally formed by additive manufacturing techniques without the need for additional processing to form the blades 710.

Referring to fig. 1, 3, 8 and 9, the rotor assembly 800 includes a rotor holder 810 and a coupling shaft 820. The rotor frame 810 includes a hub 812 and an axial diffuser 814 connected to one end of the hub 812. The sleeve 812 surrounds the coupling shaft 820 to insulate the high temperature of the combustion assembly 100 and thereby protect the coupling shaft 820. The axial diffuser 814 includes a sidewall 8142 and a plurality of axial diffuser vanes 8144 extending from the sidewall 8142 and engaged with the mounting posts 3242, when the rotor support 810 is connected with the radial diffuser 320, the axial diffuser 814 extends into the radial diffuser 320, specifically, the axial diffuser 814 extends into the accommodating space 3225 and is located between the vanes 3224 and the outer cylindrical wall 3223, and the axial diffuser vanes 8144 are engaged with the mounting posts 3242 by rotating the axial diffuser 814 to firmly connect the rotor support 810 and the radial diffuser 320. One end of the connecting shaft 820 is fixedly connected with the compressor 310, and the other end of the connecting shaft 820 penetrates through the shaft sleeve 812 and is fixedly connected with the turbine 700. The rotor bracket 810 is integrally formed by an additive manufacturing technology, that is, the shaft sleeve 812 and the axial diffuser 814 are integrated into a whole.

In operation, the motor 620 starts the compressor 310, the compressor 310 sucks in gas from the inlet 200, then the gas is diffused by the radial diffuser 320 and enters the combustion assembly 100, the gas is mixed with fuel oil in the combustion assembly 100 and is combusted, so that chemical energy of the fuel oil is converted into heat energy, the movable blades 710 of the turbine 700 are driven to rotate, the turbine 700 rotates to drive the connecting shaft 820 to rotate so as to drive the compressor 310 to rotate continuously, and thus the compressor 310 can continuously suck in gas for the micro turbojet engine 1000.

The combustion assembly 100, the inlet duct 200, the radial diffuser 320, the casing 400, the jet nozzle 500, the motor mount 610, the turbine 700, and the rotor mount 810 of the micro turbojet engine according to embodiments of the present invention are all integrally manufactured by additive manufacturing techniques, each component comprising a plurality of sub-components, such as: the casing 400 comprises a casing side wall 410, a reticular reinforcing member 420, a limiting member 430, a mounting hole 440, a first end face 460, a first fixing hole 462 and a fastening member 464, sub components which are separately assembled or need to be reprocessed by other processes are integrally manufactured, and a plurality of components are integrated into a whole, so that the supporting and connecting structures among the components are reduced, the processing is convenient, the weight is reduced, and the processing and maintenance cost and difficulty are reduced.

In some embodiments, the barrel 400 is 0.3mm thick. Thus, the thickness of the casing 400 is small, and the integrally formed mesh reinforcement member ensures the rigidity of the casing 400 and reduces the mass of the casing 400, thereby facilitating the improvement of the thrust-weight ratio.

Referring also to fig. 1, 14 and 15, in some embodiments, the combustion assembly 100 includes a liner 10 and a nozzle 20. The liner 10 includes a body 11. The body 11 is formed with a combustion chamber 111. The combustion chamber 111 includes opposing leading 1111 and trailing 1112 portions. Gas enters the combustor basket 10 from the head 1111 and exits the combustor basket 10 from the tail 1112. The nozzle 20 is arranged on the head 1111, and the nozzle 20 and the flame tube 10 are integrated into a whole and integrally manufactured through an additive manufacturing technology.

Specifically, the main body 11 is a hollow, cylindrical, thin-walled structure. The main body 11 is provided with a through hole 110. The combustion of the fuel oil in the combustion chamber 111 is mainly divided into a main combustion area, a post-combustion area and a blending area. The main combustion zone is located near the head 1111, the afterburning zone is located in the middle of the main body 11, and the blending zone is located near the tail 1112. A portion of the high pressure gas supplied by diffuser assembly 300 enters the primary combustion zone from head 1111 and is mixed with fuel and combusted. The fuel oil and the gas after being combusted in the main combustion area are further combusted in the afterburning area so as to improve the combustion efficiency of the fuel oil. And then blended with the remaining air from the outside of the liner 10 in the blending region. The blended high temperature, high pressure gas exits the liner 10 from the aft portion 1112 of the combustion chamber 111 and enters the turbine 700.

The through hole 110 communicates the combustion chamber 111 with the outside of the combustor basket 10. In the present embodiment, the outside of the combustor basket 10 refers to the area outside the combustion chamber 111, and includes the space formed by the outer sidewall of the combustor basket 10 and the casing 400, i.e. the outer annular chamber 117 (shown in fig. 1), and further includes the inner chamber 116 (shown in fig. 14). The through-hole 110 includes at least two first holes 112, and the first holes 112 are provided at a position of the body 11 near the head 1111. The gas input by diffuser assembly 300 flows along the outer sidewall of body 11. A portion of the gas continues to flow along the outer sidewall of the body 11, and a portion of the gas enters the combustion chamber 111 from the first holes 112 and continues to flow toward the tail 1112, thereby forming a cooling film on the inner sidewall of the body 11. Since the temperature of the gas entering from the first hole 112 is low, the cooling gas film is coated on the side wall of the main body 11 to cool the combustor basket 10, thereby preventing the combustor basket 10 from being excessively high in temperature. Further, the angle between the first hole 112 and the side wall of the main body 11 is an acute angle or a right angle, so that the gas enters the combustion chamber 111 in the form of a jet, and the contact area of the cooling gas film and the side wall of the main body 11 is increased, thereby better cooling the flame tube 10.

The through-hole 110 further includes at least two second holes 113. Specifically, the second hole 113 is provided at a position of the main body 11 near the tail 1112. The diameter of the second hole 113 is larger than the diameter of the first hole 112. The gas flowing along the outer side wall of the main body 11 enters the combustion chamber 111 from the second hole 113 to be mixed with the high temperature gas in the combustion chamber 111, so that the gas reaches the temperature required for the outlet of the combustion chamber 111.

The nozzle 20 is provided in the head 1111. Specifically, referring to fig. 16, the nozzle 20 includes a nozzle sidewall 21 and at least two hollow volutes 22 disposed in the nozzle sidewall 21, wherein the at least two volutes 22 communicate the outside of the flame tube 10 with the combustion chamber 111. The nozzle 20 also includes a nozzle inlet 23 and a nozzle outlet 24. The nozzle inlet 23 faces the suction inlet of the compressor 310 and the nozzle outlet 24 faces the combustion chamber 111. The high-pressure high-speed gas input from the diffuser assembly 300 enters the spiral pipe 22 from the nozzle inlet 23, is accelerated by the spiral pipe 22 and then is emitted out of the nozzle 20 from the nozzle outlet 24, so that a swirling flow with a certain cone angle opening is formed and enters the combustion chamber 111. In addition, the nozzle 20 includes a nozzle top wall 25 and a nozzle bottom wall 26. The side wall of the spiral pipe 22 is provided with an injection hole 221 so that the inside of the spiral pipe 22 and the outside of the spiral pipe 22 communicate with each other. The side walls of the coil 22, the nozzle side walls 21, the nozzle top wall 25 and the nozzle bottom wall 26 together form a fuel injection chamber 27. The fuel enters the fuel injection chamber 27 and is stored in the fuel injection chamber 27, where the fuel expands and evaporates in the fuel injection chamber 27 and is then injected into the spiral tube 22 through the injection hole 221 when the combustion assembly 100 is operated. The fuel is impacted by the high-speed air in the spiral pipe 22 and further atomized and evaporated, so that fuel-air mixture is formed, and then is sprayed out of the spiral pipe 22 and enters the combustion chamber 111 for combustion.

The type of nozzle 20 includes, but is not limited to, evaporation tube type, centrifugal atomization type, and pneumatic atomization type. Types of combustion assembly 100 include, but are not limited to, straight flow, baffled, and reverse flow.

Embodiments of the present invention also include methods for integrally designing and manufacturing the combustion assembly 100 of the micro turbojet engine 1000, comprising the steps of:

the flame tube 10 and the nozzle 20 are integrated into a whole, and the flame tube 10 and the nozzle 20 are integrally manufactured through an additive manufacturing technology. Therein, the liner 10 includes a body 11. The body 11 is formed with a combustion chamber 111. The combustion chamber 111 includes opposing leading 1111 and trailing 1112 portions. Gas enters the combustor basket 10 from the head 1111 and exits the combustor basket 10 from the tail 1112. The nozzle 20 is provided in the head 1111. That is, the nozzle 20 and the combustor basket 10 are integrated into one component.

With continuing reference to fig. 1, 14 and 15, in some embodiments, the body 11 of the liner 10 includes an inner barrel 114 and an outer barrel 115. The inner cylinder 114 is positioned in the outer cylinder 115, a combustion chamber 111 is formed between the inner cylinder 114 and the outer cylinder 115, and the nozzle 20 connects the inner cylinder 114 and the outer cylinder 115.

Specifically, the inner cylinder 114 has a hollow, cylindrical, thin-walled structure. An inner cavity 116 is formed by the sidewall of the inner barrel 114, distal from the combustion chamber 111. The inner chamber 116 communicates with the exterior of the liner 10. A connecting shaft 820 encased within the sleeve 812 is disposed through the internal cavity 116. The inner cylinder 114 is formed with a first hole 112 at a position near the head 1111 of the inner cylinder 114. The first bore 112 of the inner barrel 114 communicates the inner chamber 116 with the combustion chamber 111. The gas input by the diffuser assembly 300 enters the inner cavity 116 from the head of the inner tube 114 and then enters the combustion chamber 111 through the first hole 112 of the inner tube 114. The inner tube 114 is further cooled due to a temperature difference between the gas entering from the first holes 112 of the inner tube 114 and the high temperature gas burned in the combustion chamber 111. The inner cylinder 114 is formed with a second hole 113 at a position near the tail 1112 of the inner cylinder 114. The second hole 113 of the inner cylinder 114 communicates the combustion chamber 111 with the inner chamber 116. The gas in the inner cavity 116 enters the combustion cavity 111 from the second hole 113 of the inner cylinder 114, so as to supplement oxygen to the high-temperature fuel and gas in the combustion cavity 111, so that the fuel is fully combusted, and the temperature of the high-temperature fuel and gas in the combustion cavity 111 is further reduced, so as to reduce the temperature of the tail 1112 outlet gas.

Referring to fig. 16, the outer cylinder 115 has a hollow, cylindrical or elliptic cylindrical thin-walled structure. The inner cylinder 114 is located inside the outer cylinder 115, and a combustion chamber 111 is formed between the inner cylinder 114 and the outer cylinder 115. The diameter of the outer barrel 115 tapers to correspond with the inlet of the turbine 700 at a location near the tail 1112. The outer barrel 115 and the casing 400 form an outer annular cavity 117 (shown in FIG. 1). The outer cartridge 115 forms a first aperture 112 at a location where the outer cartridge 115 is adjacent the head 1111. The first hole 112 of the outer cylinder 115 communicates the combustion chamber 111 with the outer ring chamber 117. Part of the gas input by the diffuser assembly 300 flows along the outer sidewall of the outer barrel 115 and the inner sidewall of the casing 400 in the outer annular cavity 117, and then enters the combustion chamber 111 through the first hole 112 of the outer barrel 115. Since there is a temperature difference between the gas entering the combustion chamber 111 from the first hole 112 of the outer tub 115 and the high-temperature gas burned in the combustion chamber 111, the outer tub 115 is further cooled. The outer barrel 115 is formed with a second aperture 113 at a location of the outer barrel 115 adjacent the tail 1112. The second hole 113 of the outer cylinder 115 communicates the combustion chamber 111 with the outer ring chamber 117. The gas in the outer ring cavity 117 enters the combustion cavity 111 from the second hole 113 of the outer cylinder 115, so as to supplement oxygen to the high-temperature fuel and gas in the combustion cavity 111, so that the fuel is fully combusted, and the temperature of the high-temperature fuel and gas in the combustion cavity 111 is further reduced, so that the temperature of the tail 1112 outlet gas is reduced.

Since the inner cylinder 114 is provided with the first hole 112 at a position close to the head 1111 and the second hole 113 at a position close to the tail 1112, and the outer cylinder 115 is provided with the first hole 112 at a position close to the head 1111 and the second hole 113 at a position close to the tail 1112, the temperature of the main body 11 can be effectively reduced.

In some embodiments, at least two first holes 112 are arranged in the inner barrel 114 and the outer barrel 115 near the head 1111.

Specifically, the cross section of the body 11 is circular or elliptical. The arrangement of the first holes 112 on the body 11 is symmetrical with respect to the central axis of the body 11. Taking the cross section of the main body 11 as a circle as an example, the first holes 112 of the inner cylinder 114 are uniformly arranged on the same circumference of the inner cylinder 114 at a certain interval, or/and the first holes 112 of the outer cylinder 115 are uniformly arranged on the same circumference of the outer cylinder 115 at a certain interval. The first holes 112 of the N inner cylinders 114 may be arranged on the same circumference of the inner cylinder 114 at angular intervals of θ N ═ 360 °/N (N ≧ 2, N is a positive integer, e.g., 2, 3, 4), or/and the first holes 112 of the N outer cylinders 115 may be arranged on the same circumference of the outer cylinder 115 at angular intervals of θ N ═ 360 °/N (N ≧ 2, N is a positive integer, e.g., 2, 3, 4), that is, the first holes 112 of the inner cylinders 114 are arranged circumferentially along the side wall of the inner cylinder 114, or/and the first holes 112 of the outer cylinders 115 are arranged circumferentially along the side wall of the outer cylinder 115. The central symmetry point of the first hole 112 in the inner cylinder 114 may overlap with the central symmetry point of the first hole 112 in the outer cylinder 115, or may be offset. For example, the first holes 112 of the 12 inner cylinders 114 are disposed on the same circumference of the inner cylinders 114 at a pitch of 30 °, the first holes 112 of the 12 outer cylinders 115 are disposed on the same circumference of the outer cylinders 115 at a pitch of 30 °, and simultaneously, the centrosymmetric point of the first holes 112 of the inner cylinders 114 may overlap with the centrosymmetric point of the first holes 112 of the outer cylinders 115. The arrangement mode can also be that the first holes 112 of the plurality of inner cylinders 114 are in a group, and the first holes 112 of the plurality of groups of inner cylinders 114 are arranged on the same circumference of the inner cylinders 114 at a certain interval, or/and the first holes 112 of the plurality of outer cylinders 115 are in a group, and the first holes 112 of the plurality of groups of outer cylinders 115 are arranged on the same circumference of the outer cylinders 115 at a certain interval. Specifically, N total first holes 112 of the inner cylinders 114 are provided, the first holes 112 of each M inner cylinders 114 are in one group, and M is N/M total first holes 112 of the inner cylinders 114 are provided on the same circumference of the inner cylinders 114 at an angle θ M of 360 °/M (M is a positive integer, e.g., 1, 2, 3, 4; 1 < M ≦ N, M is a positive integer, e.g., 2, 3, 4), or/and N total first holes 112 of the outer cylinders 115 are provided, and M is N total first holes 112 of the outer cylinders 115 are provided in one group, and M is N/M total first holes 112 of the outer cylinders 115 are provided on the same circumference of the outer cylinders 115 at an angle θ M of 360 °/M (M is a positive integer, e.g., 1, 2, 3, 4; 1 < M ≦ N, M is a positive integer, e.g., 2, 3, 4). For example, 60 first holes 112 of the inner cylinder 114 are provided, and the first holes 112 of every 5 inner cylinders 114 are provided in a group, and the total number is 12. The first holes 112 of two adjacent inner cylinders 114 in each set are equally spaced, and the spacing is L1. The first holes 112 of the two adjacent sets of inner cylinders 114 are also equally spaced, and the spacing is L2. In embodiments of the present invention, L2 is greater than L1. The first holes 112 of 12 sets of the inner cylinder 114 are arranged on the same circumference of the inner cylinder 114 at a pitch of 30 °, or/and the first holes 112 of 60 outer cylinders 115 are arranged in one set of every 5 first holes 112 of the outer cylinders 115, so that there are 12 sets, and the first holes 112 of 12 sets of the outer cylinders 115 are arranged on the same circumference of the outer cylinders 115 at a pitch of 30 ° (as shown in fig. 14). Thus, the cooling air film is uniformly covered on the side walls of the inner cylinder 114 and the outer cylinder 115, which is beneficial to heat dissipation and cooling.

In other embodiments, the first holes 112 of the inner barrel 114 are uniformly arranged at certain intervals on different circumferences of the inner barrel 114, or/and the first holes 112 of the outer barrel 115 are uniformly arranged at certain intervals on different circumferences of the outer barrel 115. The diameters of the different circumferences of the body 11 may or may not be equal. The arrangement of the first holes 112 in each circumference may be the arrangement in the above-described embodiment. That is, the first holes 112 of the inner cylinder 114 may be uniformly arranged on the same circumference of the inner cylinder 114 at a certain interval, or/and the first holes 112 of the outer cylinder 115 may be uniformly arranged on the same circumference of the outer cylinder 115 at a certain interval, or the first holes 112 of a plurality of inner cylinders 114 may be in a group, and the first holes 112 of a plurality of groups of inner cylinders 114 may be arranged on the same circumference of the inner cylinder 114 at a certain interval, or/and the first holes 112 of a plurality of outer cylinders 115 may be in a group, and the first holes 112 of a plurality of groups of outer cylinders 115 may be arranged on the same circumference of the outer cylinder 115 at a certain interval. Also taking the example in which the cross section of the body 11 is circular, the first holes 112 of the N inner cylinders 114 are provided at an angle θ N of 360 °/N on the circumference 1 of the inner cylinder 114, and the first holes 112 of the N inner cylinders 114 are provided at an angle θ N of 360 °/N on the circumference 2 of the inner cylinder 114. In the axial direction of the combustor basket 10, the first holes 112 of the circumference 1 and the first holes 112 of the circumference 2 may be simultaneously arranged at the positions corresponding to the angles of the circumferences, or may be alternately arranged. For example, the first holes 112 of the 12 inner cylinders 114 are arranged at intervals of 30 ° on the circumference 1 of the inner cylinder 114, and the first holes 112 of the 12 inner cylinders 114 are arranged at intervals of 30 ° on the circumference 2 of the inner cylinder 114. The 12 first holes 112 on the circumference 1 and the 12 first holes 112 on the circumference 2 are sequentially arranged at the positions of 0 degrees, 30 degrees, 60 degrees, 90 degrees, 120 degrees, 150 degrees, 180 degrees, 210 degrees, 240 degrees, 270 degrees, 300 degrees, 330 degrees and 360 degrees of the circumference 1 and the circumference 2 of the inner barrel 114; or/and the first holes 112 of the 12 inner cylinders 114 on the circumference 1 are sequentially arranged at the positions of 0 degrees (360 degrees), 30 degrees, 60 degrees, 90 degrees, 120 degrees, 150 degrees, 180 degrees, 210 degrees, 240 degrees, 270 degrees, 300 degrees and 330 degrees on the circumference 1, and the first holes 112 of the 12 inner cylinders 114 on the circumference 2 are sequentially arranged at the positions of 15 degrees, 45 degrees, 75 degrees, 105 degrees, 135 degrees, 165 degrees, 195 degrees, 225 degrees, 255 degrees, 285 degrees, 315 degrees and 345 degrees on the circumference 2. The first holes 112 of the outer cylinder 115 are arranged in the outer cylinder 115 in the same manner as the first holes 112 of the inner cylinder 114 are arranged in the inner cylinder 114, and thus, a detailed description thereof will be omitted. The central symmetry point of the first hole 112 in the inner cylinder 114 may overlap with the central symmetry point of the first hole 112 in the outer cylinder 115, or may be staggered. The first holes 112 of the inner cylinder 114 are uniformly distributed on different circumferences of the inner cylinder 114 at certain intervals, or/and the first holes 112 of the outer cylinder 115 are uniformly distributed on different circumferences of the outer cylinder 115 at certain intervals, so that the area of the cooling air film covering the side walls of the inner cylinder 114 and the outer cylinder 115 is increased, and heat dissipation and cooling are facilitated.

In some embodiments, at least two second apertures 113 are arranged in the inner barrel 114 and the outer barrel 115 near the tail 1112.

Specifically, the cross section of the body 11 is circular or elliptical. The arrangement of the second holes 113 on the body 11 is symmetrical with respect to the central axis of the body 11. The arrangement of the at least two second holes 113 may refer to the arrangement of the at least two first holes 112 described in the above embodiments. Specifically, the second holes 113 of the inner cylinder 114 are uniformly arranged on the same circumference of the inner cylinder 114 at a certain interval, or/and the second holes 113 of the outer cylinder 115 are uniformly arranged on the same circumference of the outer cylinder 116 at a certain interval. The second holes 113 of the inner cylinder 114 can also be uniformly arranged on different circumferences of the inner cylinder 114 at certain intervals, or/and the second holes 113 of the outer cylinder 115 can also be uniformly arranged on different circumferences of the outer cylinder 115 at certain intervals. The diameters of the different circumferences of the body 11 may or may not be equal. In each circumference, the second holes 113 of the inner cylinder 114 may be uniformly arranged on the same circumference of the inner cylinder 114 at certain intervals (as shown in fig. 14), or/and the second holes 113 of the outer cylinder 115 may be uniformly arranged on the same circumference of the outer cylinder 115 at certain intervals, or the second holes 113 of the plurality of inner cylinders 114 may be in a group, and the second holes 113 of the plurality of groups of inner cylinders 114 are arranged on the same circumference of the inner cylinder 114 at certain intervals, or/and the second holes 113 of the plurality of outer cylinders 115 may be in a group, and the second holes 113 of the plurality of groups of outer cylinders 115 are arranged on the same circumference of the outer cylinder 115 at certain intervals. In the axial direction of the flame tube 10, the second holes 113 with different circumferences of the inner tube 114 may be simultaneously disposed at the positions corresponding to the angles of the different circumferences of the inner tube 114, or may be alternately disposed, or/and the second holes 113 with different circumferences of the outer tube 115 may be simultaneously disposed at the positions corresponding to the angles of the different circumferences of the outer tube 115, or may be alternately disposed. Thus, the gas entering from the tail 1112 is mixed with the high-temperature gas in the combustion chamber 111 more sufficiently, and the combustion efficiency of the fuel is improved.

Referring to fig. 15, in some embodiments, the main body 11 further includes a baffle 118 extending from the sidewalls of the outer cylinder 115 and the inner cylinder 114 to the combustion chamber 111, the baffle 118 on the inner cylinder 114 corresponds to the position of the first hole 112 of the inner cylinder 114, and the baffle 118 on the outer cylinder 115 corresponds to the position of the first hole 112 of the outer cylinder 115. Each baffle 118 is a continuous layered structure. The included angle between the baffle 118 on the outer cylinder 115 and the outer cylinder 115, and the included angle between the baffle 118 on the inner cylinder 114 and the inner cylinder 114 are acute angles. The baffle 118 of the inner cylinder 114 corresponds to the position of the first hole 112 of the inner cylinder 114, and the baffle 118 of the outer cylinder 115 corresponds to the position of the first hole 112 of the outer cylinder 115, so as to guide the flow of the gas entering the combustion chamber 111 from the first hole 112 of the inner cylinder 114 and the first hole 112 of the outer cylinder 115, so that the gas entering from the first hole 112 of the inner cylinder 114 and the first hole 112 of the outer cylinder 115 forms a film on the sidewalls of the outer cylinder 115 and the inner cylinder 114, thereby cooling the outer cylinder 115 and the inner cylinder 114.

Referring to fig. 14 and 15, in some embodiments, the through hole 110 further includes at least two third holes 119 formed at a position between the inner cylinder 114 and the outer cylinder 115, and the third holes 119 correspond to the afterburning zone. The at least two third apertures 119 of the inner barrel 114 are disposed between the first aperture 112 of the inner barrel 114 and the second aperture 113 of the inner barrel 114, or/and the at least two third apertures 119 of the outer barrel 115 are disposed between the first aperture 112 of the outer barrel 115 and the second aperture 113 of the outer barrel 115. On one hand, the gas with lower temperature enters the combustion chamber 111 through the third holes 119 of the inner cylinder 114 and the outer cylinder 115 to further cool the inner cylinder 114 and the outer cylinder 115; on the other hand, the gas introduced into the combustion chamber 111 is further mixed with the fuel and gas from the head 1111, and serves to supplement the combustion.

Referring to fig. 17 and 18, in some embodiments, the number of nozzles 20 is at least two, and at least two nozzles 20 are disposed around the inner cylinder 114. Specifically, the Q nozzles 20 are provided at the joint between the inner cylinder 114 and the outer cylinder 115 at an angle θ Q of 360 °/Q (Q ≧ 2, Q being a positive integer, e.g., 2, 3, 4). For example, 12 nozzles 20 are arranged at intervals of 30 ° on the circumference of the inner cylinder 114. In this way, the nozzle 20 provided at the head of the main body 11 can uniformly inject the fuel-air mixture into the combustion chamber 111, thereby burning the fuel and the mixture in the combustion chamber 111 with a greater composition. The nozzle 20 and the liner 10 may be connected in a manner including, but not limited to, fusion, cladding, mounting, multi-point support, and a combination thereof. For example, the head of the liner 10 is provided with a plurality of mounting slots that wrap the entire nozzle sidewall 21 to secure the nozzle 20 to the head of the liner 10; or the mounting slot may simply wrap around the bottom of the nozzle 20 to nest the nozzle 20 within the mounting slot. For another example, the inner cylinder 114 and the outer cylinder 115 of the combustor basket 10 are each provided with a plurality of claw-like support brackets, the claw-like support brackets on the inner cylinder 114 extend along the nozzle side wall 21 and abut against the nozzle bottom wall 26, and the claw-like support brackets on the outer cylinder 115 extend along the nozzle side wall 21 and abut against the nozzle top wall 25, so as to fix the nozzle 20 to the head of the combustor basket 10.

Referring to fig. 1 and fig. 15, in some embodiments, the combustion assembly 100 further includes a turbine guide vane 30, the turbine guide vane 30 is disposed on the tail 1112 and connects the inner cylinder 114 and the outer cylinder 115, the turbine guide vane 30 is located between the combustor basket 10 and the turbine 700, and the turbine guide vane 30 and the combustor basket 10 are integrated into a whole and are integrally manufactured by an additive manufacturing technology.

The turbine guide vane 30 has the function of accelerating expansion of a high-temperature and high-pressure gas working medium (working substance for realizing heat and power conversion) to obtain kinetic energy to push the movable vane 710 of the turbine 700 to do work, and meanwhile, the temperature of the expanded working medium is reduced, so that the condition of the inlet working medium of the movable vane 710 can be improved, and the service life and the safety of the movable vane 710 of the turbine 700 can be improved.

Specifically, the turbine vane 30 includes a first connection end 31, a second connection end 32, and a film hole 33. The first connecting end 31 is connected to the outer cylinder 115 near the tail 1112, and the second connecting end 32 is connected to the inner cylinder 114 near the tail 1112. The turbine vane 30 is hollow inside. The number of the film holes 33 is at least two. At least two film holes 33 are arranged in an array on a side of the turbine vane 30 adjacent to the combustion chamber 111. The film holes 33 communicate between the inside of the turbine vane 30 and the outside of the turbine vane 30. The turbine guide vane 30 is internally ventilated with cooling air, and the cooling air is ejected from the film holes 33 to form a film on the surface of the turbine guide vane 30, so as to cool and protect the turbine guide vane 30 and reduce the temperature of the outlet gas of the combustion chamber 111. In certain embodiments, at least two film holes 33 are arranged in an array on a side of the turbine vane 30 near the turbine 700, and the number of film holes 33 near the combustion chamber 111 is greater than the number of film holes 33 near the turbine 700, so as to further protect the turbine vane 30 from cooling and reduce the temperature of the exit gas of the combustion chamber 111.

The integrated design and manufacturing method of the combustion assembly 100 of the micro turbojet engine 1000 according to the embodiment of the invention further comprises the following steps:

the flame tube 10 and the turbine guide vane 30 are integrated into a whole, and the flame tube 10 and the turbine guide vane 30 are integrally designed and manufactured through an additive manufacturing technology. The liner 10 includes a body 11, the body 11 defining a combustion chamber 111, the combustion chamber 111 including opposing head 1111 and tail 1112, gas entering the liner 10 from the head 1111 and exiting the liner 10 from the tail 1112. The turbine vane 30 is disposed at the tail 1112 and connects the inner barrel 114 with the outer barrel 115. That is, the turbine guide vane 30 and the combustor basket 10 are integrated into one component.

The combustion assembly 100 of the micro turbojet engine 1000 is integrally designed and manufactured by using an additive manufacturing technology, the flame tube 10 and the turbine guide vane 30 are integrated, the structure of the combustion assembly 100 can be simplified, the supporting and connecting structures among all parts of the combustion assembly 100 are reduced, the processing is convenient, the weight is reduced, the reliability is improved, and the processing and maintenance cost is reduced.

Referring to FIG. 15, in some embodiments, the inner barrel 114 further includes an annular base 1141, and the base 1141 is connected to the second connection end 32. The base 1141 is provided with a mounting hole 1142. The mounting holes 1142 are used to mount the turbine 700. A connecting shaft 820 surrounded by the sleeve 812 extends through the interior 116 and is connected to the turbine 700. As such, the base 1141 increases the support strength of the combustor basket 10 to better support the turbine vane 30 and the turbine 700. In the embodiment of the present invention, the number of the mounting holes 1142 is three, but of course, in other embodiments, the number of the mounting holes 1142 is not limited to 3, such as 2, 4 or more.

Referring to fig. 19 and 20, in some embodiments, the combustion assembly 100 further includes a fuel line 40, the fuel line 40 is disposed on a side wall of the outer cylinder 115, and the fuel line 40 and the flame tube 10 are integrated into a single body and are integrally manufactured by an additive manufacturing technique. The fuel line 40 functions to preheat and vaporize fuel, i.e., to preheat the vaporizing tube, during operation of the combustion assembly 100. Meanwhile, the fuel pipeline 40 also has the effect of increasing the strength of the outer cylinder 115 with a thin-wall structure, namely, has the function of reinforcing the outer cylinder 115.

Specifically, the fuel line 40 includes a main pipe 41, a distribution chamber 42, and a branch pipe 43.

The main tube 41 is provided on the side wall of the outer cylinder 115, extending in a direction in which the head 1111 is directed to the tail 1112. One end of the main pipe 41 is used for connecting an external fuel source. In the embodiment of the present invention, the number of the main pipes 41 is one, but of course, in other embodiments, the number of the main pipes 41 may be plural.

The distribution chamber 42 extends in a direction perpendicular to the head 1111 toward the tail 1112 and communicates with the other end of the main tube 41. The dispensing chamber 42 is circumferentially disposed on the outer barrel 115.

The branch pipe 43 extends in a direction from the head 1111 toward the tail 1112, and one end of the branch pipe 43 communicates with the distribution chamber 42 and the other end communicates with the nozzle 20. The branch pipes 43 are provided on the inner side surface of the outer cylinder 115. The number of branch pipes 43 is at least two. The number of branch pipes 43 is equal to the number of nozzles 20 and corresponds in position. At least two branch pipes 43 are provided on the outer cylinder 115 at an angle θ W of 360 °/W (W ≧ 2, W being a positive integer, e.g., 2, 3, 4). The fuel supplied from the external fuel source is preheated and evaporated while passing through the main pipe 41, and then enters the plurality of branch pipes 43 through the distribution chamber 42, is further evaporated while passing through the plurality of branch pipes 43, and then enters the injection nozzle 20.

The integrated design and manufacturing method of the combustion assembly 100 of the engine 1000 according to the embodiment of the present invention further includes the steps of:

the flame tube 10 and the fuel oil pipeline 40 are integrated into a whole, and the flame tube 10 and the fuel oil pipeline 40 are integrally designed and manufactured through an additive manufacturing technology. The liner 10 includes a body 11, the body 11 defining a combustion chamber 111, the combustion chamber 111 including opposing head 1111 and tail 1112, gas entering the liner 10 from the head 1111 and exiting the liner 10 from the tail 1112. The fuel line 40 is disposed on a side wall of the outer barrel 115. The fuel line 40 includes a main pipe 41, a distribution chamber 42, and a branch pipe 43. A main tube 41 extends in a direction from the head 1111 to the tail 1112, and one end of the main tube 41 is used for connecting an external fuel source. The distribution chamber 42 extends in a direction perpendicular to the head 1111 toward the tail 1112 and communicates with the other end of the main tube 41. The branch 43 extends in a direction from the head 1111 towards the tail 1112, one end of the branch 43 communicating with the distribution chamber 42 and the other end communicating with the nozzle 20. That is, the fuel line 40 and the liner 10 are integrated into one component.

The combustion assembly 100 of the engine 1000 is integrally manufactured by using an additive manufacturing technology, the flame tube 10 and the fuel oil pipeline 40 are integrated into a whole, the structure of the combustion assembly 100 can be simplified, the supporting and connecting structures among all parts of the combustion assembly 100 are reduced, the processing is convenient, the weight is reduced, the reliability is improved, and the processing and maintenance cost is reduced.

In certain embodiments, the nozzle 20 and the liner 10 are integrally designed and manufactured by additive manufacturing techniques; or/and the turbine guide vane 30 and the flame tube 10 are integrally designed and manufactured through an additive manufacturing technology; or/and the fuel pipeline 40 and the flame tube 10 are integrally designed and manufactured through an additive manufacturing technology. Specifically, the nozzle 20, the turbine guide vane 30, and the fuel line 40 may be integrally designed and manufactured with the combustor basket 10 at the same time by additive manufacturing techniques; or the nozzle 20, the fuel pipeline 40 and the flame tube 10 are integrally designed and manufactured through an additive manufacturing technology, and then the turbine guide vane 30 manufactured through the additive manufacturing technology is assembled on the flame tube 10; or the turbine guide vane 30 and the fuel pipeline 40 are integrally designed and manufactured with the flame tube 10 by an additive manufacturing technology, and then the nozzle 20 manufactured by the additive manufacturing technology is assembled on the flame tube 10.

The invention utilizes the additive manufacturing technology to carry out integrated design and manufacture on the combustion assembly 100 of the micro turbojet engine 1000, and integrates the flame tube 10, the nozzle 20, the turbine guide vane 30 and the fuel oil pipeline 40 into a whole, thereby simplifying the structure of the combustion assembly 100, reducing the supporting and connecting structures among all parts of the combustion assembly 100, facilitating the processing, being beneficial to reducing weight, improving the reliability and reducing the processing and maintenance cost.

Referring to fig. 21, 22 and 23, in some embodiments, the liner 10 is designed to have one or more sections according to requirements of vibration characteristics, strength, thermal deformation, etc., that is, the liner 10 has a one-section structure or the liner 10 has a multi-section structure. The multiple sections mean two or more sections.

Specifically, the nozzle 20, the turbine guide vane 30, the fuel pipeline 40, and the combustor basket 10 are integrally and simultaneously manufactured by an additive manufacturing technology, and the combustor basket 10 has a one-stage structure.

The two-stage flame tube 10 includes a first stage 12 and a second stage 13. The head 1111 is formed at the first section 12, the first section 12 is formed with a first opening 121 opposite to the head 1111, and the first section 12 is formed with a groove 122 on the outer wall thereof. The tail 1112 is formed on the second section 13, the second section 13 is formed with a second opening 131 opposite to the tail 1112, a protrusion 132 is formed on the outer wall of the second section 13, and the protrusion 132 is matched with the groove 122 to communicate the first opening 121 and the second opening 131 (as shown in fig. 24). The number of the grooves 122 may be plural, and the number of the protrusions 132 is equal to the number of the grooves 122 and corresponds to the position. The groove 122 is provided at an angle θ R of 360 °/R (R ≧ 2, R being a positive integer, e.g., 2, 3, 4) at a position of the first section 12 near the first opening 121, and the projection 132 is provided at an angle θ R of 360 °/R at a position of the second section 13 near the second opening 131. For example, 3 recesses 122 are respectively provided at 120 ° intervals at positions of the first section 12 near the first opening 121, and 3 protrusions 132 are correspondingly provided at positions of the second section 13 near the second opening 131.

Referring to fig. 22, in some embodiments, a positioning block 123 is formed on the first section 12 near the first opening 121. The number of the positioning blocks 123 is at least two. When the first section 12 and the second section 13 are assembled, the positioning block 123 abuts against the second section 13, so that the protrusion 132 of the second section 13 is conveniently clamped into the groove 122 of the first section 12.

The structure of the multi-section flame tube 10 is similar to that of the two-section flame tube 10 in the above embodiment. The flame tube 10 is designed into multiple sections, and has the following beneficial effects:

1. from the viewpoint of vibration characteristics: the flame tube 10 is designed in sections, and the natural frequency of the flame tube 10 is easy to change according to the requirement of the vibration characteristic of the flame tube 10, so that a quick and effective means is provided for solving the problem of thermoacoustic oscillation in the design process of the combustion chamber 111 in engineering.

2. From the strength and rigidity point of view: the sectional design of the flame tube 10 can change the rigid constraint condition of the whole flame tube 10, reduce the rigidity of the whole structure, facilitate to reduce the stress level when the flame tube 10 is loaded externally, and prolong the service life.

3. From the point of view of thermal deformation and thermal stress: the liner 10 is subjected to high temperature and thermally deforms when in an operating state, and thermal stress is generated when thermal deformation is restrained. The sectional design of the flame tube 10 can change the rigid constraint condition when the flame tube 10 is subjected to thermal deformation, which is beneficial to reducing the thermal stress level when the flame tube 10 is in a working state and prolonging the service life.

The integrated design and manufacturing method of the micro turbojet engine 1000 according to the embodiment of the present invention includes the following steps:

the motor bracket 610 is integrally formed by an additive manufacturing technique.

The air inlet duct 200 is integrally formed by an additive manufacturing technique.

The diffuser is formed integrally by fusing the diffuser portion and the connecting portion into a whole through an additive manufacturing technology.

The casing 400 is integrally formed by an additive manufacturing technique.

The jet nozzle 500 is integrally formed by additive manufacturing techniques.

The flame tube 10 and the fuel oil pipeline 40 are integrated into a whole, and the flame tube 10 and the fuel oil pipeline 40 are integrally designed and manufactured through an additive manufacturing technology. That is, the fuel line 40 and the liner 10 are integrated into one component.

The turbine 700 is integrally formed by additive manufacturing techniques.

The rotor support is integrally formed by an additive manufacturing technology.

The invention integrally manufactures a combustion assembly 100, an air inlet 200, a radial diffuser 320, a casing 400, a tail nozzle 500, a motor support 610, a turbine 700 and a rotor support of a micro turbojet engine 1000 by using an additive manufacturing technology, and integrally manufactures a plurality of separately assembled components, wherein each component comprises a plurality of sub-components, such as: the casing 400 includes a casing sidewall 410, a mesh reinforcement member 420, a limiting member 430, a mounting hole 440, a first end surface 460, a first fixing hole 462 and a fastening member 464, and these sub-components that are separately assembled or need to be reprocessed by other processes are integrally manufactured, so that the supporting and connecting structures among the components are reduced, the processing is facilitated, the weight reduction is facilitated, and the cost and difficulty of the processing and maintenance are reduced. The whole micro turbojet engine 1000 provided by the invention has a simple structure, only comprises not more than 15 3D printing structural components, and comprises 2 motor supports 610 (namely a first mounting part 612 and a second mounting part 614), a motor 620, a bearing and less than 30 connecting pieces 900 (such as bolts).

The additive manufacturing technology of the embodiment of the invention comprises the following processes:

the three-dimensional CAD design drawing is stored in a format which can be identified by the slicing software of the additive manufacturing equipment, the file is imported into the slicing software for slicing, and the 3D printer executes codes generated by the slicing software for 3D printing.

The integrated design and manufacturing method of the additive manufacturing technology of the embodiment of the invention is that the selective laser melting: and slicing and layering the three-dimensional CAD model of the part through slicing software, focusing a high-energy laser beam on an area to be formed after contour data of each section is obtained, selectively melting metal powder layer by layer, and finishing additive manufacturing in a mode of spreading powder layer by layer and melting, solidifying and accumulating layer by layer. The metal material according to the embodiment of the present invention is a titanium alloy, a nickel alloy, or the like.

Specifically, the flow of the additive manufacturing technique of the embodiment of the present invention includes the following steps:

1. determining the pneumatic appearance of the micro turbojet engine 1000 according to the performance index requirements of the micro turbojet engine 1000, and completing the design of a macroscopic outline;

2. according to the weight reduction, strength, cooling and material increase manufacturing process of the micro turbojet engine 1000, the integrated design of the combustion assembly 100, the air inlet channel 200, the radial diffuser 320, the casing 400, the tail nozzle 500, the motor support 610, the turbine 700 and the rotor support is completed;

3. and performing numerical simulation, checking function and structural strength on the design model completed in the steps. And when any one of the technical indexes does not meet the requirement, returning to the previous step for optimization design, and entering the next step until all simulation analysis results are qualified.

4. And (3) performing additive manufacturing on all parts meeting the design requirements of the product, and performing subsequent processes such as heat treatment, wire cutting, machining and the like until the assembly requirements of the parts are met.

In summary, the micro turbojet engine 1000 according to the embodiment of the present invention has the following beneficial effects:

1. the structure of the micro turbojet engine 1000 is simplified, and the overall weight of the micro turbojet engine 1000 is reduced;

2. the structure of the micro turbojet engine 1000 is simpler through the integrated molding of the additive manufacturing technology, and the structural stability of the micro turbojet engine 1000 is good while the performance of the micro turbojet engine 1000 is ensured;

3. the manufacturing cost of the combustion assembly 100 of the micro turbojet engine 1000 is greatly reduced through the integrated molding of the additive manufacturing technology, and meanwhile, the later maintenance cost is reduced;

4. the intermediate links of design, manufacture and experiment are reduced, the flow is simplified, and the research and development period is shortened.

In the description of the specification, reference to the terms "certain embodiments," "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a particular feature, structure, material, or characteristic described in connection with the embodiments or examples is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, unless specifically limited otherwise.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and those skilled in the art can make changes, modifications, substitutions and alterations to the above embodiments within the scope of the present invention, which is defined by the claims and their equivalents.

Claims

1. A micro turbojet engine of additive design, said micro turbojet engine comprising:

a case;

the radial diffuser is connected with the head of the casing, and the radial diffuser and the casing are integrally manufactured by an additive manufacturing technology;

the flame tube is arranged in the casing, the main body of the flame tube comprises an inner tube and an outer tube, the inner tube is positioned in the outer tube, and a combustion cavity is formed between the inner tube and the outer tube; and

the nozzle is connected with the inner cylinder and the outer cylinder, the number of the nozzles is at least two, the at least two nozzles are arranged around the inner cylinder, each nozzle comprises a nozzle side wall, a nozzle top wall, a nozzle bottom wall and at least two hollow spiral pipes arranged in the nozzle side wall, the side walls of the spiral pipes are provided with jet holes, so that the inside of each spiral pipe and the outside of each spiral pipe are communicated, the at least two spiral pipes are communicated with the outside of the flame tube and the combustion chamber, and the side walls of the spiral pipes, the nozzle side walls, the nozzle top wall and the nozzle bottom wall form an oil injection chamber together;

the nozzle also comprises a nozzle inlet and a nozzle outlet, and the gas input from the radial diffuser enters the spiral pipe from the nozzle inlet and is emitted to the combustion chamber from the nozzle outlet; fuel is injected into the spiral pipe through the injection hole to be mixed with gas in the spiral pipe to form fuel-air mixed gas;

the radial diffuser comprises a diffuser top wall, an inner cylinder wall extending from the diffuser top wall and an outer cylinder wall extending from the diffuser top wall and surrounding the inner cylinder wall; the connecting part extends from the outer cylinder wall, the connecting part comprises an installation column extending from the inner side wall, the installation column comprises an installation section and a reinforcing section, an installation hole is formed in one end, connected with the radial diffuser, of the casing, the micro turbojet engine further comprises a connecting piece, and the connecting piece penetrates through the installation hole and the installation section to connect the radial diffuser and the casing; the reinforcing section is of a wedge-shaped structure.

2. The micro turbojet engine of claim 1 wherein the case includes a case sidewall and a web reinforcement extending from an inner surface of the case sidewall.

3. The micro turbojet engine of claim 1, further comprising a retainer extending from an inner surface of the side wall of the case, the micro turbojet engine further comprising a combustion assembly disposed within the case, the retainer being configured to retain the combustion assembly.

4. The micro turbojet engine of claim 1, wherein the diffuser portion and the connecting portion are integrally formed by an additive manufacturing technique.

5. The micro turbojet engine of claim 1, wherein a receiving space is formed between the inner and outer cylindrical walls, the diffuser further including a plurality of vanes extending from the diffuser top wall and received in the receiving space, the plurality of vanes configured to restrict a flow direction of the airflow.

6. The micro turbojet engine of claim 1, further comprising a motor bracket and a motor, wherein the motor bracket includes a first mounting portion and a second mounting portion, when the first mounting portion is coupled to the second mounting portion, an accommodating cavity is formed between the first mounting portion and the second mounting portion, the motor is accommodated in the accommodating cavity, and the first mounting portion and the second mounting portion are integrally formed by an additive manufacturing technique.

7. The micro turbojet engine of claim 6, further comprising an inlet duct, one end of the inlet duct being connected to the motor support, the other end of the inlet duct being connected to the diffuser, the micro turbojet engine further comprising a compressor, the compressor being connected to the motor and penetrating the inlet duct.

8. The micro turbojet engine of claim 1 further comprising a jet nozzle fixedly attached to the other end of the case, the jet nozzle being integrally formed by additive manufacturing techniques.

9. The micro turbojet engine of claim 8, wherein the rear portion of the casing defines a first end surface, the first end surface defines a plurality of first fastening holes, the end of the tailpipe coupled to the casing defines a flange extending from a sidewall of the tailpipe, the flange includes a second end surface engaged with the first end surface, the second end surface defines a plurality of second fastening holes, and the coupling member extends through the second fastening holes and the first fastening holes to fixedly couple the tailpipe to the casing.