Pintle injector and liquid rocket engine

Abstract

The utility model relates to a pintle injector and a liquid rocket engine. The pintle injector comprises a needle valve (10) and a shell (11). A plurality of flow guide vertical grooves (15) are formed in the outer surface of the positioning guide cylinder (13) at intervals in the circumferential direction of the positioning guide cylinder (13); an outer ring propellant is introduced from an outer ring propellant inlet (17) in a shell (11), enters a ring groove (16) and is sprayed out from an outer ring spray hole (20) after being guided by flow guide vertical grooves (15), and meanwhile, the outer surface of a vertical partition plate between every two adjacent flow guide vertical grooves (15) is in contact with the inner surface of the shell (11), so that the coaxial matching degree between a needle valve (10) and the shell (11) can be improved without higher machining precision, and the machining efficiency is improved. The gap uniformity of the outer ring spray holes (20) between the outer conical surface (18) and the inner conical surface (19) is guaranteed, the injection uniformity of outer ring propellants is prevented from being affected, the assembly effect is structurally guaranteed, the manufacturing cost is reduced, and the manufacturing period is shortened.

Description

Technical Field

[0001] The utility model relates to the technical field of pintle injectors, in particular to a pintle injector and a liquid rocket engine. Background Art

[0002] The collision form of the two-way propellant of the pintle injector is generally: the center-way slot (or circular hole) structure and the outer ring integral annular seam structure, the center-way propellant is injected along the radial direction of the injector, and the outer ring propellant is injected along the axial direction of the injector, and the two-way propellant completes combustion after collision. When assembling the pintle injector, in order to ensure that the gap between the needle valve and the cone surface of the shell is uniform, so as to avoid affecting the injection uniformity of the outer ring propellant, it is necessary to improve the processing accuracy of the parts, thereby improving the coaxial fit during assembly, increasing the manufacturing cost and cycle. Utility Model Content

[0003] The technical problem to be solved by the utility model is that during the assembly of the existing needle bolt injector, in order to ensure that the gap between the needle valve and the conical surface of the shell is uniform so as to avoid affecting the injection uniformity of the outer ring propellant, it is necessary to improve the processing accuracy of the parts, thereby improving the coaxial fit during assembly, which increases the manufacturing cost and cycle.

[0004] In order to solve the above problems, the utility model provides a needle plug injector, including a needle valve and a shell. The needle valve is inserted into the shell. The needle valve includes an end seat, a positioning guide cylinder and a needle head which are arranged in sequence from top to bottom. The end seat is connected to the upper end of the shell. The outer surface of the positioning guide cylinder is provided with a plurality of guide vertical grooves spaced along its circumference. The inner surface of the shell is provided with an annular groove which is connected with the guide vertical groove. The shell is provided with an outer ring propellant inlet which is connected with the annular groove. An outer conical surface is formed between the positioning guide cylinder and the needle head. The inner surface of the shell is provided with an inner conical surface. The inner conical surface and the outer conical surface are gap-matched to form an outer ring spray hole. The outer ring spray hole is connected with the guide vertical groove.

[0005] The needle bolt injector provided by the utility model also has the following technical features:

[0006] A central passage is formed inside the needle valve, a central propellant inlet communicating with the central passage is arranged at the upper end of the needle valve, and an annular radial spray hole is arranged at the lower end of the needle valve, which is communicated with the central passage.

[0007] A central rod is arranged inside the needle valve, a baffle is arranged at the lower end of the central rod, the lower end of the needle valve is open, and an annular radial spray hole is formed between the lower end of the needle valve and the baffle.

[0008] The upper end of the needle valve is provided with a connecting cylinder, which is arranged inside the needle valve through a plurality of ribs, a central propellant inlet is formed between adjacent ribs, and the upper end of the central rod is inserted into the connecting cylinder.

[0009] The end seat is connected to the upper end of the shell through bolts, and a fastening gasket is sleeved on the bolts.

[0010] A first mounting groove is provided at the upper end of the housing, a supporting gasket is provided in the first mounting groove, and the supporting gasket is in contact with the end seat;

[0011] A connecting section is provided between the end seat and the positioning guide cylinder, a mounting step is formed between the connecting section and the positioning guide cylinder, a second mounting groove is formed on the housing, and a sealing gasket is provided in both the mounting step and the second mounting groove.

[0012] The utility model has the following beneficial effects: the outer ring propellant is introduced into the annular groove through the outer ring propellant inlet on the outer shell, and is sprayed out from the outer ring spray hole after being guided by the guide vertical groove. At the same time, the outer surface of the vertical partition between adjacent guide vertical grooves contacts the inner surface of the outer shell, so that the coaxial fit between the needle valve and the outer shell can be improved without higher processing accuracy, so as to ensure the uniformity of the gap between the outer cone surface and the inner cone surface of the outer ring spray hole, avoid affecting the uniformity of the injection of the outer ring propellant, ensure the assembly effect from the structural point of view, and reduce the manufacturing cost and cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a cross-sectional view of the utility model;

[0014] Figure 2 for Figure 1 A partial enlarged view of

[0015] Figure 3 A partial cross-sectional view of a needle valve. DETAILED DESCRIPTION

[0016] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0017] like Figures 1 to 3 As shown, the first embodiment of the utility model provides a needle plug injector, including a needle valve 10 and a shell 11. The needle valve 10 is inserted into the shell 11. The needle valve 10 includes an end seat 12, a positioning guide cylinder 13 and a needle head 14 which are arranged in sequence from top to bottom. The end seat 12 is connected to the upper end of the shell 11. The outer surface of the positioning guide cylinder 13 is provided with a plurality of guide vertical grooves 15 spaced along its circumferential direction. The inner surface of the shell 11 is provided with an annular groove 16, which is communicated with the guide vertical groove 15. The shell 11 is provided with an outer ring propellant inlet 17 which is communicated with the annular groove 16; an outer cone 18 is formed between the positioning guide cylinder 13 and the needle head 14, and an inner cone 19 is provided on the inner surface of the shell 11. The inner cone 19 and the outer cone 18 are clearance-matched to form an outer ring spray hole 20, and the outer ring spray hole 20 is communicated with the guide vertical groove 15.

[0018] The outer ring propellant is introduced into the annular groove 16 through the outer ring propellant inlet 17 on the outer shell 11, and is sprayed out from the outer ring spray hole 20 after being guided by the guide vertical groove 15. At the same time, the outer surface of the vertical partition between adjacent guide vertical grooves 15 contacts the inner surface of the outer shell 11, so that the coaxial fit between the needle valve 10 and the outer shell 11 can be improved without higher processing accuracy, so as to ensure the uniformity of the gap of the outer ring spray hole 20 between the outer cone surface 18 and the inner cone surface 19, avoid affecting the uniformity of the injection of the outer ring propellant, ensure the assembly effect from the structural point of view, and reduce the manufacturing cost and cycle.

[0019] The specific size and spacing of the guide grooves 15 can be set according to actual application. The multiple guide grooves 15 have the same size, and the width of the guide grooves 15 and the spacing between adjacent guide grooves 15 are small, so as to form a circumferential liquid film.

[0020] The inner surface of the lower end of the housing 11 is also provided with an annular surface, and the annular surface and the outer conical surface 18 of the outer surface of the needle valve 10 form an axial spray hole, so that the outer ring spray hole 20 can spray the outer ring propellant in the axial direction.

[0021] Preferably, a central passage 21 is formed inside the needle valve 10 , a central propellant inlet 22 communicating with the central passage 21 is provided at the upper end of the needle valve 10 , and an annular radial spray hole 23 is provided at the lower end of the needle valve 10 , and the radial spray hole 23 is communicated with the central passage 21 .

[0022] An annular radial spray hole 23 is provided at the lower end of the needle valve 10 to ensure that the central propellant sprayed from the radial spray hole 23 collides with the outer ring propellant sprayed from the outer ring spray hole 20 to form a circumferentially mixed liquid film, thereby improving the combustion stability.

[0023] Preferably, a center rod 24 is provided inside the needle valve 10 , a baffle 25 is provided at the lower end of the center rod 24 , and the lower end of the needle valve 10 is open, and an annular radial spray hole 23 is formed between the baffle 25 .

[0024] The center rod 24 can be configured to slide up and down along the needle valve 10, and a corresponding driving mechanism, such as a hydraulic drive, pneumatic or electric push rod, is disposed at the upper end of the center rod 24 to adjust the height of the radial spray hole 23, thereby changing the injection amount of the central propellant.

[0025] Preferably, see Figure 3 The upper end of the needle valve 10 is provided with a connecting tube 26, which is arranged inside the needle valve 10 through a plurality of ribs 27. A central propellant inlet 22 is formed between adjacent ribs 27, and the upper end of the central rod 24 is passed through the connecting tube 26.

[0026] The center rod 24 can slide up and down along the connecting tube 26 .

[0027] Of course, the connecting tube 26 can be directly fixed to the needle valve 10, and a guide hole can be opened on the inner wall of the connecting tube 26 or the outer wall of the center rod 24 to form a central propellant inlet.

[0028] Preferably, the end seat 12 is connected to the upper end of the housing 11 via a bolt 28 , and a fastening gasket 29 is sleeved on the bolt 28 .

[0029] Preferably, a first mounting groove 30 is provided at the upper end of the housing 11, a supporting gasket 31 is provided in the first mounting groove 30, and the supporting gasket 31 is in contact with the end seat 12;

[0030] A connecting section 32 is provided between the end seat 12 and the positioning guide cylinder 13 , and a mounting step 33 is formed between the connecting section 32 and the positioning guide cylinder 13 . A second mounting groove 34 is formed on the housing 11 , and a sealing gasket 35 is provided in both the mounting step 33 and the second mounting groove 34 .

[0031] The supporting gasket 31 is a metal gasket to adjust the assembly gap between the outer cone surface 18 and the inner cone surface 19 ; the sealing gasket 35 is a non-metallic gasket, such as polytetrafluoroethylene, to achieve a sealing effect between the needle valve 10 and the housing 11 .

[0032] Preferably, a combustion chamber 36 is formed at the lower end of the housing 11 .

[0033] The second embodiment of the present utility model provides a liquid rocket engine, which adopts the pintle injector described in the first embodiment. Other structures of the liquid rocket engine are prior art and will not be described in detail here.

[0034] The working principle of the needle bolt injector of the utility model is as follows:

[0035] The outer ring propellant is introduced from the outer ring propellant inlet 17 on the outer shell 11, and enters the annular groove 16, and is sprayed from the outer ring spray hole 20 after being guided by the guide vertical groove 15. The central propellant is introduced from the central propellant inlet 22 at the upper end of the needle valve 10, passes through the central passage 21 and is sprayed from the annular radial spray hole 23, and collides with the outer ring propellant to form a circumferentially mixed and uniform liquid film, thereby improving the combustion stability; at the same time, the outer surface of the vertical partition between the adjacent guide vertical grooves 15 contacts the inner surface of the outer shell 11, so that the coaxial fit between the needle valve 10 and the outer shell 11 can be improved without higher processing accuracy, so as to ensure the uniformity of the gap of the outer ring spray hole 20 between the outer cone surface 18 and the inner cone surface 19, avoid affecting the injection uniformity of the outer ring propellant, ensure the assembly effect from the structural point of view, and reduce the manufacturing cost and cycle.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A pintle injector, characterized in that: The needle valve (10) comprises a needle valve (10) and a housing (11). The needle valve (10) is inserted into the housing (11). The needle valve (10) comprises an end seat (12), a positioning guide cylinder (13) and a needle head (14) arranged in sequence from top to bottom. The end seat (12) is connected to the upper end of the housing (11). The outer surface of the positioning guide cylinder (13) is provided with a plurality of flow guide vertical grooves (15) spaced apart along its circumferential direction. The inner surface of the housing (11) is provided with an annular groove (16). (16) is connected to the flow guide vertical groove (15), and the outer shell (11) is provided with an outer ring propellant inlet (17) connected to the annular groove (16); an outer cone surface (18) is formed between the positioning guide cylinder (13) and the needle head (14), and an inner cone surface (19) is provided on the inner surface of the outer shell (11), and the inner cone surface (19) and the outer cone surface (18) are clearance-matched to form an outer ring spray hole (20), and the outer ring spray hole (20) is connected to the flow guide vertical groove (15).

2. The pintle injector according to claim 1, characterized in that: A central passage (21) is formed inside the needle valve (10), a central propellant inlet (22) communicating with the central passage (21) is provided at the upper end of the needle valve (10), and an annular radial spray hole (23) is provided at the lower end of the needle valve (10), the radial spray hole (23) communicating with the central passage (21).

3. The pintle injector according to claim 2, characterized in that: A central rod (24) is provided inside the needle valve (10), a baffle (25) is provided at the lower end of the central rod (24), and the lower end of the needle valve (10) is open, forming an annular radial spray hole (23) between the lower end of the needle valve (10) and the baffle (25).

4. The pintle injector according to claim 3, characterized in that: A connecting tube (26) is provided at the upper end of the needle valve (10). The connecting tube (26) is arranged inside the needle valve (10) via a plurality of ribs (27). A central propellant inlet (22) is formed between adjacent ribs (27). The upper end of the central rod (24) is inserted into the connecting tube (26).

5. The pintle injector according to claim 1, characterized in that: The end seat (12) is connected to the upper end of the housing (11) via a bolt (28), and a fastening gasket (29) is sleeved on the bolt (28).

6. The pincer injector according to claim 1, characterized in that: A first mounting groove (30) is provided at the upper end of the housing (11), a supporting gasket (31) is provided in the first mounting groove (30), and the supporting gasket (31) is in contact with the end seat (12); A connecting section (32) is provided between the end seat (12) and the positioning guide cylinder (13), a mounting step (33) is formed between the connecting section (32) and the positioning guide cylinder (13), a second mounting groove (34) is formed on the housing (11), and a sealing gasket (35) is provided in both the mounting step (33) and the second mounting groove (34).

7. The pintle injector according to claim 1, characterized in that: A combustion chamber (36) is formed at the lower end of the housing (11).

8. A liquid rocket engine, characterized in that: A pincer injector comprising the pincer injector according to any one of claims 1 to 7.

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