3D printing based two-component centrifugal ignition nozzle and engine head injector

Abstract

The application discloses a kind of based on 3D printing's two-component coaxial centrifugal ignition nozzle and direct-flow type head injector using self-ignition igniter ignition. Among them, the ignition nozzle includes shell, liquid oxygen flow passage, kerosene and igniter flow passage, liquid oxygen flow passage is arranged at the center position of shell, kerosene and igniter flow passage is arranged at the ring direction position of shell.The ignition nozzle and injector provided by the application have strong structural rigidity, lightweight design, simple heat protection, good product consistency, effectively solve the current vortex ignition nozzle in long-range work often occurs nozzle end surface ablation, make the engine have multiple stable and reliable ignition capacity, at the same time, the lightweight design of injector solves the problem of large machining difficulty and long production cycle of traditional injector.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of liquid rocket engine, and particularly relates to a double-component centrifugal ignition nozzle based on 3D printing and an engine head injector. BACKGROUND

[0002] The commonly used ignition modes of liquid rocket engine include electric spark ignition, torch ignition, solid gunpowder ignition and self-ignition agent ignition. For liquid oxygen kerosene engine, the propellant is non-self-igniting propellant, and a corresponding igniter is needed to ignite and burn and generate thrust. The most commonly used ignition mode for liquid oxygen kerosene engine is self-ignition agent ignition. Since no energy stimulation is needed, the ignition agent can spontaneously burn after contacting with oxygen, realizing the ignition of liquid oxygen and kerosene. This scheme is simple and reliable, and can be ignited multiple times.

[0003] For liquid oxygen kerosene engine with straight-flow injector and self-ignition agent ignition at the head, the ignition nozzles and injectors produced by traditional processing mode have the following shortcomings:

[0004] 1. The traditional centrifugal ignition nozzle mainly performs centrifugal atomization through the vortex structure arranged in the shell. However, the size of the swirl chamber and the swirl structure will affect the outlet velocity. The helix angle and the number of grooves of the swirl will significantly affect the atomization angle of the nozzle, thereby resulting in high requirement for the machining precision of this structure, and the parts can only be assembled after precision machining, so the structure cannot adapt to the 3D printing integrated molding technology.

[0005] 2. The ignition mode of the thrust chamber is related to the ignition performance and reliability of the thrust chamber, and therefore it is required to be able to quickly ignite, reliably start and stably work. For liquid oxygen kerosene engine with large thrust, the structure with straight-flow impingement type injector and self-ignition agent ignition is particularly critical for stable and reliable ignition. The traditional structure commonly uses vortex type ignition nozzle for ignition. The kerosene and the ignition agent share one flow channel, i.e. they are sprayed out from the inner flow channel through the vortex. When the engine ignites, the ignition agent is first atomized and sprayed out from the inner flow channel, and then self-ignites after encountering the oxygen sprayed out from the nearby nozzle. After successful ignition, the kerosene and the ignition agent are switched, and the kerosene atomized and sprayed out from the inner flow channel mixes with the oxygen sprayed out from the outer flow channel to ignite the entire combustion chamber. When the traditional vortex type ignition nozzle ignites, the oxygen is sprayed out from the outer gap of the nozzle, and an oxygen-rich environment is formed around the spray. The end face in the center is insufficiently cooled, which to some extent leads to the phenomenon of end face ablation of the ignition nozzle during the hot test, and in severe cases, it may cause the ablation of the injection surface, and therefore it cannot meet the use requirement of the engine with multiple stable and reliable start ignitions.

[0006] 3. The blanks of the head injectors of traditional direct current nozzles are mostly made of castings, forgings or thick plates, and then the injectors are produced as a whole through finishing and brazing. Due to process limitations, this method has a relatively small overall structure and is suitable for the production of small pulse engines or small thrust engine heads. For high-thrust engines, due to the larger engine structure, structural stiffness, lightweight design, thermal protection and performance issues must be considered. In addition, the complexity of machining, welding and other processes brought about by structural changes increases dramatically, which not only greatly reduces reliability, but also increases production cycle and cost. At the same time, due to the limitations of traditional machining processes, the injector flow path cannot be arranged compactly, resulting in a relatively large head structure and mass. Therefore, traditional production methods are no longer suitable for the production of high-thrust direct current injectors.

[0007] 4. Traditional DC engine head injectors generally use castings, forgings or thick plates for their main parts. For injectors with disc and ring structures, after the injector disc blank is machined on the forging, radial holes are finely machined along the circumference of the side wall surface, and annular grooves of different sizes for the flow of oxidizer and fuel are milled on the back of the injector disc. Then, the machined nozzle hole and nozzle ring are embedded in the grooves and connected by brazing. Finally, the oxygen chamber shell and fuel ring and other components are welded. When machining the radial hole of the injector disc, due to the small center hole diameter, the machining is difficult, the precise machining of the positioning surface is labor-intensive and time-consuming, and the process is complicated.

[0008] 5. To ensure the flow characteristics and sealing requirements of the propellant, welding quality is also required to be extremely high. Traditional methods often have high welding process requirements, multiple welds, and differences in mechanical properties between the base material and the brazing material, which leads to stress concentration at the brazing seams. In addition, there are still many welding steps after brazing, which easily cause the injector to deform and crack, resulting in poor injector reliability.

[0009] With the advancement of 3D additive technology, parts with complex structures and high machining difficulty have become a better choice through one-piece molding using 3D additive technology, which can reduce production costs while improving work reliability. Summary of the Invention

[0010] In view of this, the main purpose of the present invention is to provide a two-component centrifugal ignition nozzle and engine head injector based on 3D printing.

[0011] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0012] A two-component centrifugal ignition nozzle based on 3D printing, characterized in that it includes a shell, a liquid oxygen circulation channel, and a kerosene and ignition agent circulation channel. The liquid oxygen circulation channel is arranged at the center position of the shell, and the kerosene and ignition agent circulation channel is arranged at a circumferential position of the shell.

[0013] Further, the liquid oxygen flow passage comprises a central hole, a liquid oxygen inlet passage and a liquid oxygen outlet passage, the central hole is vertically arranged at the center of the lower part of the shell, the liquid oxygen inlet passage is arranged in several and arranged along the ring direction of the shell, the liquid oxygen inlet passage is communicated with the upper side of the central hole, the liquid oxygen outlet passage is arranged in several and arranged along the ring direction of the shell, the liquid oxygen outlet passage is communicated with the lower side of the central hole.

[0014] Further, the liquid oxygen inlet passage is tangent to the ring direction of the shell.

[0015] Further, the kerosene and ignition agent flow passage comprises a flow passage, a kerosene and ignition agent inlet passage and a kerosene and ignition agent outlet passage, the flow passage is vertically arranged at the center of the upper part of the shell, the kerosene and ignition agent inlet passage is arranged in several and arranged along the ring direction of the shell, the kerosene and ignition agent inlet passage is communicated with the flow passage, the kerosene and ignition agent outlet passage is arranged in several and arranged along the ring direction of the shell.

[0016] Further, the kerosene and ignition agent outlet passage is tangent to the ring direction of the shell.

[0017] Further, the position of the liquid oxygen outlet passage is higher than that of the kerosene and ignition agent outlet passage.

[0018] The application also provides a 3D printing-based engine head injector, characterized in that it comprises the ignition nozzle, the flow equalizing shell, the outer bottom, the middle bottom and the inner bottom as described above, the ignition nozzle is arranged at the center of the outer bottom through the flow equalizing shell; the outer bottom and the middle bottom enclose a columnar cavity, the inner bottom separates the cavity, the upper part forms a liquid oxygen cavity and the lower part forms a combustion chamber, the middle bottom has an annular fuel cavity on the outer periphery of the inner bottom, a plurality of fuel ring cavities and liquid oxygen ring cavities are arranged in an annular array on the inner bottom at one end of the combustion chamber, a plurality of fuel radial drainage holes are arranged in a radial circumferential array on the inner bottom at one end of the liquid oxygen cavity, a plurality of liquid oxygen flow guide holes are arranged in an axial circumferential array on the inner bottom at one end of the liquid oxygen cavity, the outer end of the fuel radial drainage hole is communicated with the fuel cavity, the inner end is communicated with the corresponding lower fuel ring cavity on one side, the upper end of the liquid oxygen flow guide hole is communicated with the liquid oxygen cavity, and the lower end is communicated with the corresponding lower liquid oxygen ring cavity; the outer bottom, the flow equalizing shell, the middle bottom and the inner bottom are integrally formed with the ignition nozzle, the fuel ring cavity and the liquid oxygen ring cavity.

[0019] Further, the fuel ring cavity and the liquid oxygen ring cavity are arranged in sequence according to concentric circles, so that the liquid oxygen and kerosene can be atomized and mixed at different positions of the injector.

[0020] Further, the injector is integrally formed with the middle bottom, the inner bottom and the ignition nozzle, the fuel ring cavity and the liquid oxygen ring cavity by combining 3D additive technology, and is subjected to air tightness test detection through a tool, after the detection is completed, the middle bottom and the inner bottom are processed, the ignition nozzle assembly hole is machined, after assembly, electron beam welding or laser welding is adopted for welding, and finally, the outer bottom and the remaining parts are welded by adopting hand argon welding to form the injector.

[0021] Compared with the prior art, the present application has the following advantages and effects:

[0022] (1) Compared with the prior art, the ignition nozzle based on 3D printing avoids the problems of high requirement of traditional processing technology, many welds and complex process, adopts the coaxial double centrifugal retraction ignition nozzle structure, reduces the area of the injection end surface of the ignition nozzle, the liquid oxygen flows through the inner flow channel, the kerosene and the ignition agent switch in the outer flow channel, the cooling property of the ignition nozzle is enhanced, the end surface ablation problem of the ignition nozzle is effectively solved, and the engine has the requirement of multiple ignition.

[0023] (2) Compared with the traditional nozzle structure, the nozzle integrally printed by using the 3D additive printing technology has the characteristics of good consistency and high coaxiality, can reduce the problems of poor uniformity and consistency of the vortex generator caused by the traditional machining and welding scheme, is integrally formed with the radial hole and the oxygen flow guide hole, obviously reduces the welds, reduces the production cost, shortens the production and processing cycle, and meets the low-cost and high-efficiency industry demand.

[0024] (3) The direct-flow engine head injector provided by the present application is no longer limited by machining, welding and other processes in structure, can be integrally formed by 3D printing, solves the heat protection problem through the fuel cavity and oxygen cavity structure arranged in the injector, has high integrity and good rigidity, greatly meets the design requirement of light weight, and since the angle and position degree of the outlet hole are required to be very high in the direct-flow impingement type injection mode, the impingement atomization effect of the propellant is ensured, therefore, the injection ring adopts fine machining punching or brazing direct-flow nozzle to ensure high-quality impingement atomization.

[0025] (4) Compared with the traditional direct-flow engine head injector, the fuel cavity and oxygen cavity structure arranged in the engine head injector of the present application achieves the effect of uniform flow of the propellant, avoids the flow pulsation of the cavity, enhances the anti-interference ability of the outlet, makes the outlet flow atomization stable and uniform, and significantly improves the stability of combustion. At the same time, the closed cavity can be subjected to hydraulic air tightness detection, which not only judges the quality of the printed product, but also provides a judgment basis for judging whether the oxidizing agent cavity and the fuel cavity are in series. Compared with the traditional welding structure, the risk of series cavity is greatly avoided, and for the large-thrust engine, the stability and reliability of the engine are ensured.

[0026] (5) The 3D printing based engine head injector provided by the application is not limited in structure by machining, welding and other processes, is integrally formed by 3D printing, solves the heat protection problem through the inner cavity structure of the injector, has high integrity, good rigidity, compact structure and greatly meets the design requirement of light weight. BRIEF DESCRIPTION OF DRAWINGS

[0027] The drawings described herein are used to disclose further understanding of the application, constitute a part of the application, the illustrative embodiments of the application and the description thereof are used to explain the application and do not constitute improper limitation on the application. In the drawings:

[0028] Figure 1 The first sectional view of the 3D printing based double-component centrifugal ignition nozzle is provided for the embodiment of the application.

[0029] Figure 2 The second sectional view of the 3D printing based double-component centrifugal ignition nozzle is provided for the embodiment of the application. Figure 1 The sectional view of the F-F direction.

[0030] Figure 3 The second sectional view of the 3D printing based double-component centrifugal ignition nozzle is provided for the embodiment of the application.

[0031] Figure 4 The sectional view of the C-C direction. Figure 1 The sectional view of the O-O direction.

[0032] Figure 5 The sectional view of the O-O direction. Figure 1 The sectional view of the O-O direction.

[0033] Figure 6 The sectional view of the 3D printing based engine head injector is provided for the embodiment of the application.

[0034] Figure 7 The sectional view of the A-A direction. Figure 6 The sectional view of the A-A direction.

[0035] Figure 8 The sectional view of the B-B direction. Figure 6 The sectional view of the B-B direction.

[0036] Figure 9 The sectional view of the C-C direction. Figure 6 The sectional view of the C-C direction.

[0037] Figure 10 The sectional view of the D-D direction. Figure 6 The sectional view of the D-D direction.

[0038] Reference signs:

[0039] 1-shell; 2-liquid oxygen circulation channel; 3-ignition agent circulation channel; 31-flow channel; 32-kerosene and ignition agent inlet channel; 33-kerosene and ignition agent outlet channel; 4-fire nozzle; 5-fuel ring cavity; 6-liquid oxygen ring cavity; 7-inner bottom; 8-outer bottom; 9-flow uniform shell; 10-middle bottom; 11-injection surface; 21-center channel; 22-liquid oxygen inlet channel; 23-liquid oxygen outlet; 51-fuel injection ring; 52-fuel injection hole, 53-fuel tangential hole, 61-liquid oxygen injection ring; 62-liquid oxygen injection hole; 63-liquid oxygen tangential hole; 71-fuel radial diversion hole, 72-liquid oxygen guide hole, 81-liquid oxygen cavity; 82-fuel cavity, 821-first fuel fuel cavity; 822-second fuel fuel cavity, 83-combustion chamber. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0041] The same or similar numbers in the drawings of this embodiment correspond to the same or similar parts; in the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", "inner", "outer", etc. indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0042] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, article, or device comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, article, or device comprising the element.

[0043] like Figures 1-5 An embodiment of the present invention provides a 3D-printed bi-component centrifugal ignition nozzle, comprising a housing 1, a liquid oxygen flow channel 2, and a kerosene and ignition agent flow channel 3. The liquid oxygen flow channel 2 is disposed at the center of the housing 1, and the kerosene and ignition agent flow channel 3 is disposed circumferentially around the housing 1.

[0044] The liquid oxygen circulation channel 2 includes a central channel 21, a liquid oxygen inlet channel 22, and a liquid oxygen outlet channel 23. The central channel 21 is vertically arranged at the center of the lower part of the shell 1. A plurality of liquid oxygen inlet channels 22 are provided and arranged along the circumferential direction of the shell 1. The liquid oxygen inlet channels 22 are all connected to the upper side of the central channel 21. A plurality of liquid oxygen outlet channels 23 are provided and arranged along the circumferential direction of the shell 1. The liquid oxygen outlet channels 23 are all connected to the lower side of the central channel 21.

[0045] The liquid oxygen inlet channel 22 is tangential to the annular direction of the shell 1 .

[0046] The kerosene and ignition agent circulation channel 3 includes an overflow channel 31, a kerosene and ignition agent inlet channel 32, and a kerosene and ignition agent outlet channel 33. The overflow channel 31 is vertically arranged at the center of the upper part of the shell 1. Several kerosene and ignition agent inlet channels 32 are vertically arranged and arranged along the circumferential direction of the shell 1. The kerosene and ignition agent inlet channels 32 are all connected to the overflow channel 31. Several kerosene and ignition agent outlet channels 33 are arranged and arranged along the circumferential direction of the shell 1.

[0047] The kerosene and ignition agent outlet passage 33 is tangential to the annular direction of the housing 1 .

[0048] The position of the liquid oxygen outlet channel 23 is higher than the positions of the kerosene and ignition agent outlet channels 33 .

[0049] The ignition agent flowing in from the kerosene and ignition agent circulation channel 3 enters the annular cavity through the flow channel, and then is sprayed out and atomized through the kerosene and ignition agent outlet channel 33, and spontaneously ignites. After the ignition is completed, the kerosene and ignition agent circulation channel 3 is switched, and the sprayed kerosene is mixed with the oxygen atomized sprayed from the liquid oxygen outlet channel 23 and burns.

[0050] like Figures 6-10 As shown. An embodiment of the present invention also provides an engine head injector based on 3D printing, comprising an ignition nozzle 4, a fuel annulus 5, a liquid oxygen annulus 6, an inner bottom 7, an outer bottom 8, a flow balancing shell 9, and a middle bottom 10. The inner bottom 7, middle bottom 10, and outer bottom 8 are arranged sequentially from bottom to top and are integrally formed with the ignition nozzle 4, the fuel annulus 5, and the liquid oxygen annulus 6. The ignition nozzle 4 is arranged at the center of the outer bottom 8 through the flow balancing shell 9. The fuel annulus 5 and the liquid oxygen annulus 6 are arranged in an annular array on the inner circumference of the inner bottom 7. The bottom surface of the inner bottom 7 forms an injection surface 11. The port arrays of the fuel annulus 5 and the liquid oxygen annulus 6 are spaced apart and distributed on the surface of the injection surface 11.

[0051] The outer sole 8 is a spherical cap surface, the outer periphery of the middle sole 10 is formed into a drum-shaped curved surface, the inner layer 7 is arranged in the inner periphery of the middle sole 10, and the upper end of the middle sole 10 is connected with the outer sole 8 into an integrated whole. The outer sole 8 and the middle sole 10 are formed into a cap cylindrical cavity, and the inner layer 7 separates the inside of the cavity. The inner cavity above the inner layer 7 is formed into a liquid oxygen cavity 81, the inner cavity below the inner layer 7 is formed into a combustion chamber 83, and the drum-shaped curved surface of the middle sole 10 inside the outer periphery of the inner layer 7 is provided with an annular fuel cavity 82. The liquid oxygen cavity 81 is annularly sleeved on the outer periphery of the flow equalizing shell 9 to form an annular cavity.

[0052] The fuel cavity 82 comprises a first fuel cavity 821 and a second fuel cavity 822. The first fuel cavity 821 is in a fan-shaped structure in cross section, and is arranged below the drum-shaped curved surface of the outer periphery of the inner layer 7. The second fuel cavity 822 is in a polygonal structure in cross section, and is arranged above the first fuel cavity 821. The first fuel cavity 821 and the second fuel cavity 822 are in communication through an annular overflow hole. The outer periphery of the first fuel cavity 821 is provided with a fuel adding port, and fuel enters the second fuel cavity 822 from the first fuel cavity 821. The first fuel cavity 821 and the second fuel cavity 822 are arranged in a ring shape to form a liquid collecting ring cavity in the outer periphery of the middle sole 10.

[0053] A plurality of liquid oxygen ring cavities 6 are arranged in an annular array to form a liquid oxygen cavity group ring, and a plurality of fuel ring cavities 5 are arranged in an annular array to form a fuel cavity group ring. The liquid oxygen cavity group ring and the fuel cavity group ring are arranged in a concentric distribution.

[0054] The liquid oxygen cavity group ring and the fuel cavity group ring are arranged in a spaced array in the entire axial direction of the inner layer 7. One end of each of the liquid oxygen ring cavities 6 and the fuel ring cavities 5 is located on the injection surface 11 of the inner layer 7.

[0055] One end of each of the fuel ring cavities 5, which communicates with the injection surface 11, is provided with a fuel injection ring 51. The fuel injection ring 51 is provided with fuel injection holes 52 in the axial direction and penetrates the fuel ring cavity 5. One end of each of the liquid oxygen ring cavities 6, which communicates with the injection surface 11, is provided with a liquid oxygen injection ring 61. The liquid oxygen injection ring 61 is provided with liquid oxygen injection holes 62 in the axial direction and penetrates the liquid oxygen ring cavity 6.

[0056] Axial liquid oxygen flow guide holes 72 are arranged in a circumferential array on the upper end surface of the inner layer 7. A plurality of liquid oxygen flow guide holes 72 are arranged in a circumferential array to form a liquid oxygen flow guide hole group ring. The number of the liquid oxygen flow guide hole group ring is consistent with that of the liquid oxygen cavity group ring. A plurality of liquid oxygen flow guide hole group rings are arranged in a concentric manner. The lower end of each of the liquid oxygen flow guide holes 72 communicates with the upper end of the liquid oxygen ring cavity 6 through a liquid oxygen tangential hole 63. The upper ends of all the liquid oxygen flow guide holes 72 communicate with the liquid oxygen cavity 81.

[0057] The inner bottom 7 is provided with a plurality of fuel radial flow holes 71 arranged in a circumferential array in the horizontal radial direction. One end of the fuel radial flow hole 71 is in communication with the first fuel fuel cavity, and the other end of the fuel radial flow hole 71 extends along the ignition nozzle 4 end of the center of the inner bottom 7. Each fuel radial flow hole 71 is spaced apart from the liquid oxygen flow hole 72 in sequence. The outer periphery of each fuel radial flow hole 71 is provided with a fuel tangential hole 53 and an upper end of the fuel annular cavity 5 in sequence.

[0058] As shown again in Figures 1-5 The ignition nozzle 4 includes a shell 1, a liquid oxygen flow passage 2, and a kerosene and igniter flow passage 3. The liquid oxygen flow passage 2 is arranged at the center of the shell 1, and the kerosene and igniter flow passage 3 is arranged at the annular position of the shell 1.

[0059] The liquid oxygen flow passage 2 includes a central channel 21, a liquid oxygen inlet passage 22, and a liquid oxygen outlet passage 23. The central channel 21 is arranged vertically at the center of the lower part of the shell 1. A plurality of liquid oxygen inlet passages 22 are arranged annularly along the shell 1, and each is in communication with the upper side of the central channel 21. A plurality of liquid oxygen outlet passages 23 are arranged annularly along the shell 1, and each is in communication with the lower side of the central channel 21.

[0060] The liquid oxygen inlet passage 22 is tangent to the annular direction of the shell 1.

[0061] The kerosene and igniter flow passage 3 includes a flow passage 31, a kerosene and igniter inlet passage 32, and a kerosene and igniter outlet passage 33. The flow passage 31 is arranged vertically at the center of the upper part of the shell 1. A plurality of kerosene and igniter inlet passages 32 are arranged vertically and annularly along the shell 1, and each is in communication with the flow passage 31. A plurality of kerosene and igniter outlet passages 33 are arranged annularly along the shell 1.

[0062] The kerosene and igniter outlet passage 33 is tangent to the annular direction of the shell 1.

[0063] The position of the liquid oxygen outlet passage 23 is higher than that of the kerosene and igniter outlet passage 33.

[0064] The igniter flowing from the kerosene and igniter flow passage 3 enters the annular cavity through the flow channel, and is sprayed and atomized through the kerosene and igniter outlet passage 33. The oxygen is self-ignited when it meets the oxygen, and after the ignition is completed, the kerosene and igniter flowing from the kerosene and igniter flow passage 3 is mixed with the oxygen atomized from the liquid oxygen outlet passage 23 and burns.

[0065] Liquid oxygen ring cavity 6 and fuel ring cavity 5 are arranged in sequence in concentric circles, so that liquid oxygen and kerosene can be uniformly atomized and mixed at the injection surface of the injector, the combustion efficiency is enhanced, and guarantee conditions are provided for high-efficiency and stable combustion of liquid oxygen and kerosene under a large range of variable conditions.

[0066] Liquid oxygen inlets are arranged on the flow equalizing shell 9 and communicate with the liquid oxygen cavity 81, so that the liquid oxygen inlets form ring cavities through the flow equalizing shell, the fuel inlets are provided with fuel cavities 82 to form liquid collecting ring cavities, flow pulsation of the cavities is avoided, the anti-interference capability of the outlet is enhanced, the atomized and stable and uniform outlet flow is achieved, and the stability of combustion is significantly improved.

[0067] The boss structure is arranged at the outlet of the ignition nozzle 4, the inner surface of the nozzle outlet is easy to be scratched during machining and test experiments, the atomization performance of the nozzle is affected, a large ignition impact is caused, and combustion instability occurs during operation, the boss is processed in the last machining process, the inner surface of the nozzle outlet is effectively ensured, and the performance influence of the nozzle caused by scratching is avoided.

[0068] The fuel ring cavity 5 and the liquid oxygen ring cavity 6 are arranged in the inner circle of the concentric circles, the injection performance of the injector is significantly improved due to good atomization performance, and the combustion efficiency is enhanced.

[0069] The ignition nozzle 4 meets the head structure design of the coaxial double-centrifugal injector arrangement and self-ignition, the ignition agent and kerosene are switched while the stable ignition requirement is met, and ablation of the injection surface of the engine during operation after switching is avoided.

[0070] The engine head injector in the above-mentioned embodiment is also provided, the injector is integrally formed by combining 3D additive technology, the outer bottom 8, the middle bottom 10, the inner bottom 7, the ignition nozzle 4, the fuel ring cavity 5 and the liquid oxygen ring cavity 6, the fuel cavity 82 and the liquid oxygen cavity 81 are subjected to airtight test detection through a tool, the risk of cavity connection is effectively avoided, the reliability of the injector work is improved, the middle bottom 10 and the inner bottom 7 are processed after detection, the ignition nozzle assembly hole is machined, after assembly, the electron beam welding or laser welding with small welding stress is adopted, the injector cracking caused by the large welding stress generated by the traditional hand argon welding is avoided, finally, the outer bottom and the remaining parts are welded by using the hand argon welding mode, the closed cavity and each nozzle can be detected by adopting the processing mode of combining the 3D printing process, the difficult brazing process is avoided, the welding seam is reduced, the production and processing cycle is shortened, and the low-cost and high-efficiency industry demand is met.

[0071] The 3D additive technology is used for integrated printing, the uniformity and consistency problem caused by the machining and welding scheme is reduced, under the condition that the roughness meets the requirement, the flow characteristics of the fluid deviating from the design due to defects of the nozzle itself in the production process are avoided.

[0072] The application is integrally formed in combination with 3D additive technology, avoids the complexity of traditional production process, significantly reduces the welding seam, reduces the production cost, shortens the processing cycle, and improves the working reliability.

[0073] The 3D additive technology can realize the detection of the closed cavity of the head and each nozzle, avoid the complex process that each nozzle needs to be connected by brazing, and avoid the stress concentration caused by the brazing filler and the inconsistent mechanical properties of the base body, which provides a judgment basis for judging whether the oxidizing agent cavity and the fuel cavity are connected.

[0074] The above is only a preferred embodiment of the application, and is not used to limit the protection scope of the application.

Claims

1. A 3D printing based engine head injector characterized in that, The ignition nozzle, the flow equalizing shell, the outsole, the midsole and the insole, the ignition nozzle is arranged in the center of the outsole through the flow equalizing shell; the outsole and the midsole enclose a columnar cavity, and the insole separates the cavity, the upper part forms a liquid oxygen cavity, the lower part forms a combustion chamber, the midsole on the outer periphery of the insole has an annular fuel cavity, a plurality of fuel ring cavities and liquid oxygen ring cavities are distributed in an annular array on the insole at one end of the combustion chamber, a plurality of fuel radial drainage holes are arranged in a radial circumferential array on the insole at one end of the liquid oxygen cavity, a plurality of liquid oxygen flow guide holes are arranged in an axial circumferential array on the insole at one end of the liquid oxygen cavity, the outer end of the fuel radial drainage hole is communicated with the fuel cavity, the inner end is communicated with the corresponding lower fuel ring cavity on one side, the upper end of the liquid oxygen flow guide hole is communicated with the liquid oxygen cavity, and the lower end is communicated with the corresponding lower liquid oxygen ring cavity; the outsole, the flow equalizing shell, the midsole, the insole, the ignition nozzle, the fuel ring cavity and the liquid oxygen ring cavity are integrally formed; The ignition nozzle comprises a shell, a liquid oxygen flow passage and a kerosene and ignition agent flow passage, the liquid oxygen flow passage is arranged at the center position of the shell, and the kerosene and ignition agent flow passage is arranged at the annular position of the shell; The ignition nozzle adopts a coaxial double-centrifugal retracted ignition nozzle structure; the liquid oxygen flows through the inner flow channel, and the kerosene and ignition agent flow through the outer flow channel and are switched; The liquid oxygen cavity is annularly sleeved on the outer periphery of the flow equalizing shell to form an annular cavity; The ignition agent flowing from the kerosene and ignition agent flow passage enters the annular cavity through the flow channel, is then sprayed and atomized through the kerosene and ignition agent outlet passage, is self-ignited when meeting oxygen, and the kerosene sprayed from the kerosene and ignition agent flow passage is mixed and burned with the oxygen sprayed from the liquid oxygen outlet passage after the ignition is completed; A liquid oxygen inlet is arranged on the flow equalizing shell, the liquid oxygen inlet is communicated with the liquid oxygen cavity, an annular cavity is formed by the flow equalizing shell at the liquid oxygen inlet, and a fuel cavity is arranged at the fuel inlet to form a liquid collecting annular cavity.

2. The 3D printing based engine head injector of claim 1, wherein, The liquid oxygen flow passage comprises a center hole, a liquid oxygen inlet passage and a liquid oxygen outlet passage, the center hole is arranged at the center of the lower part of the shell along the vertical direction, a plurality of liquid oxygen inlet passages are arranged and arranged along the annular direction of the shell, the liquid oxygen inlet passages are all communicated with the upper side of the center hole, a plurality of liquid oxygen outlet passages are arranged and arranged along the annular direction of the shell, and the liquid oxygen outlet passages are all communicated with the lower side of the center hole.

3. The 3D printing based engine head injector of claim 2, wherein, The liquid oxygen inlet passage is tangent to the annular direction of the shell.

4. The 3D printing based engine head injector of claim 3, wherein, The kerosene and ignition agent flow passage comprises a flow passage, a kerosene and ignition agent inlet passage and a kerosene and ignition agent outlet passage, the flow passage is arranged at the center of the upper part of the shell along the vertical direction, a plurality of kerosene and ignition agent inlet passages are arranged along the vertical direction and arranged along the annular direction of the shell, the kerosene and ignition agent inlet passages are all communicated with the flow passage, and a plurality of kerosene and ignition agent outlet passages are arranged and arranged along the annular direction of the shell.

5. The 3D printing based engine head injector of claim 4, wherein, The kerosene and ignition agent outlet passage is tangent to the annular direction of the shell.

6. The 3D printing based engine head injector of claim 5, wherein, The position of the liquid oxygen outlet passage is higher than that of the kerosene and ignition agent outlet passage.

7. The 3D printing based engine head injector of claim 1, wherein, The fuel ring cavity and the liquid oxygen ring cavity are arranged in sequence according to concentric circles, so that the liquid oxygen and the kerosene can be atomized and mixed at different positions of the injector.

8. The 3D printing based engine head injector of claim 1, wherein, The injector is integrally formed by combining 3D additive technology, a middle bottom, an inner bottom, an ignition nozzle, a fuel ring cavity and a liquid oxygen ring cavity, and is subjected to airtight test detection by a tool, after the detection is completed, the middle bottom and the inner bottom are processed, the ignition nozzle assembly hole is machined, after assembly, electron beam welding or laser welding is adopted for welding, and finally hand argon welding is adopted for welding the outer bottom and the remaining parts to form the injector.

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