A three-shot injector

Abstract

A three-strike injector is composed of an injection disk, a fuel shell, a fuel nozzle and an oxidizer nozzle, wherein the middle part of the injection disk is conical, the interior is an oxidizer chamber, an upper boss is provided on the top of the injection disk, a circular hole is opened in the center of the upper boss, and the circular hole is connected to the oxidizer chamber; a lower boss is provided at the bottom of the injection disk, and regularly arranged flow channel holes, a three-strike injection hole group and a fuel cooling hole are provided in the lower boss; the fuel shell is fixedly connected to the upper boss and the lower boss of the injection disk by welding, the fuel shell and the conical side of the injection disk form a fuel chamber on the circumference, and are connected to the fuel nozzle by welding; the nozzle chamber of the fuel nozzle is connected to the fuel chamber; a circular groove is designed on the top of the fuel shell, which is fixedly connected to the oxidizer nozzle by welding. The present invention optimizes the injector structure, has a simple process and precise manufacturing, can efficiently atomize, mix and burn the propellant, and improves the combustion efficiency.

Description

Technical Field

[0001] The invention relates to a three-shot injector, which belongs to the technical field of aerospace and liquid rocket engines and is used for a power supply system of a liquid rocket engine. Background Art

[0002] Liquid rockets are generally composed of fairings, instrument cabins, interstages, oxidizer tanks and fuel tanks, pressurization and delivery systems, engines, tail sections, and other parts. Liquid rocket engines are mainly composed of gas generators, turbopumps, thrust chambers, and various valves and pipelines. The role of the gas generator in a liquid engine is to atomize, mix, and burn the propellant to produce high-temperature and high-pressure combustion gas with very high energy, which then expands further to do work and drive the turbine to run at high speed, thereby driving the turbopump to make the liquid rocket engine work and provide power for the entire rocket. The gas generator is mainly composed of an injector and a combustion chamber. Among them, the injector is a key component for atomizing and mixing the propellant, which directly affects the working performance of the gas generator;

[0003] At present, the injectors used in gas generators at home and abroad are mostly welded together from scattered sheet metal parts. They are not only complex in structure, but also difficult to manufacture. In particular, for a large number of welded nozzles, the welding accuracy is difficult to guarantee. There are problems with the propellant atomization and mixing effect, and the inability to burn efficiently in the combustion chamber. Some of them lead to low combustion efficiency, some lead to high temperature in the combustion chamber, and even burn the gas generator. Summary of the invention

[0004] The technical problem solved by the present invention is: it changes the design and manufacturing scheme of the injectors used in the existing gas generators, simplifies the structure of the injection disk, changes the method of atomizing and mixing the propellant, overcomes the problem of low combustion efficiency and even high temperature in the combustion chamber, which seriously affects the working performance of the gas generator, and proposes a new three-strike injector, which changes the roughly positioned welded nozzle into a single-module processed injection hole form, with simple process and precise manufacturing. Its unique three-strike injection hole group can achieve efficient atomization and mixing of the propellant in a limited space, thereby improving the combustion efficiency; at the same time, the fuel cooling hole provides liquid film cooling protection for the combustion zone, avoiding high temperature in the combustion chamber. This technical solution is suitable for injectors using fuel and oxidant bicomponent propellants, filling the design gap in this technical field at home and abroad;

[0005] The technical solution of the present invention is: a three-strike injector, comprising an injection disk (1), a fuel agent shell (2), a fuel agent nozzle (3) and an oxidant nozzle (4), wherein the middle portion of the injection disk (1) is conical, the interior of the cone is an oxidant chamber (13), an upper boss (11) is provided on the top of the injection disk (1), a circular hole (12) is opened in the center of the upper boss (11), and the circular hole (12) is connected to the oxidant chamber (13); the injection disk (1) ) is provided with a lower boss (14) at the bottom, and regularly arranged flow channel holes (15), a three-shot injection hole group (16) and a fuel agent cooling hole (19) are provided in the lower boss (14); the three-shot injection hole group (16) includes two fuel agent holes (17) and an oxidant hole (18), wherein the fuel agent hole (17) is connected to the flow channel hole (15), and the oxidant hole (18) is connected to the oxidant chamber (13); the fuel agent shell (2 ) is fixedly connected to the upper boss (11) and the lower boss (14) of the injection disk (1) by welding, the fuel shell (2) and the conical side of the injection disk (1) form a fuel cavity (21) on the circumference, the fuel cooling holes (19) are located in the bottom edge area of ​​the lower boss (14) of the injection disk (1) and are evenly distributed along the circumference and are connected to the fuel cavity (21); a side hole (22) is opened on one side of the fuel shell (2) and is connected to the fuel cavity (21). The fuel nozzle (3) is fixedly connected by welding; the fuel nozzle (3) is cylindrical, and has a nozzle cavity (31) inside, which is communicated with the fuel cavity (21); a circular groove (23) is provided on the top of the fuel shell (2), which is fixedly connected with the oxidant nozzle (4) by welding; the oxidant nozzle (4) is overall conical, and the nozzle cavity (41) inside is communicated with the circular hole (12) of the injection disk (1) and the oxidant cavity (13);

[0006] The flow channel holes (15) are evenly distributed along the conical side surface of the injection disk (1) and are connected to the fuel chamber (21);

[0007] There are three groups of flow channel holes (15), each group is evenly distributed along the circumference, wherein the length of the first group of flow channel holes (15) along the radial direction is 5 mm to 50 mm smaller than the radius of the injection disk (1); the length of the second group of flow channel holes (15) along the radial direction is 25 mm to 75 mm smaller than the radius of the injection disk (1); the length of the third group of flow channel holes (15) along the radial direction is 50 mm to 100 mm smaller than the radius of the injection disk (1); the flow channel holes (15) evenly distributed in the form of intervals in the first group of flow channel holes (15) or the second group of flow channel holes (15) are interconnected in the radial direction;

[0008] The one oxidant hole (18) is located between the two fuel holes (17), the axes of the two fuel holes (17) and the axis of the one oxidant hole (18) form an angle of 5° to 85°, and the three axes intersect at one point;

[0009] The fuel shell (2) is in the shape of a ring as a whole, and has a side hole (22) on the side; a circular groove (23) and an upper circular hole (24) are provided at the upper end, and a lower circular hole (25) is provided at the lower end, wherein the upper circular hole (24) is fixedly connected to the upper boss (11) of the injection disk (1) by welding, and the lower circular hole (25) is fixedly connected to the lower boss (14) of the injection disk (1) by welding;

[0010] The three-strike injector of the present invention has the following working process: when the fuel enters the annular fuel chamber (21) through the nozzle chamber (31) of the fuel nozzle (3), flows through the flow channel hole (15), and then is injected into the combustion chamber through the fuel hole (17) of the three-strike injection hole group (16); at the same time, the oxidant enters the circular hole (12) and the oxidant chamber (13) of the injection disk (1) through the nozzle chamber (41) of the oxidant nozzle (4), and then passes through the oxidant hole (17) of the three-strike injection hole group (16). The three-shot injection hole (18) is used to inject the fuel into the combustion chamber; the two fuels injected from the two fuel holes (17) of the three-shot injection hole group (16) and the one oxidant injected from the one oxidant hole (18) of the three-shot injection hole group (16) collide and atomize, mix and burn; at the same time, the fuel is directly injected into the combustion chamber through the fuel cooling hole (19) at the bottom edge area of ​​the injection disk (1), and the fuel evaporates at high temperature to form a cooling layer at the edge area, which not only reduces the wall temperature, but also enhances the mixing effect, thereby avoiding high temperature in the combustion chamber;

[0011] The advantages of the present invention compared with the prior art are: the present invention applies an injector with a single-module injection disk to the field of liquid rocket engine gas generators, which is not only easy to manufacture and simple to process, but also improves the positioning accuracy of the three-shot injection hole group, and can achieve efficient atomization, mixing and combustion of fuel and oxidizer, thereby improving combustion efficiency; at the same time, the fuel sprayed into the fuel cooling hole evaporates at high temperature to form a side cooling layer, which not only reduces the wall temperature but also enhances the mixing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a front cross-sectional view of a three-strike injector structure according to the present invention;

[0013] Figure 2 A front cross-sectional view of a fuel shell of a three-shot injector according to the present invention;

[0014] Figure 3 A three-dimensional cross-sectional view of an injection disk of a three-strike injector according to the present invention;

[0015] Figure 4 A front cross-sectional view of a fuel agent nozzle of a three-strike injector according to the present invention;

[0016] Figure 5A front cross-sectional view of an oxidant nozzle of a three-strike injector according to the present invention;

[0017] Figure 6 A bottom-view cross-sectional view of a first group of flow channel holes of an injection disk of a three-strike injector according to the present invention;

[0018] Figure 7 A bottom-view cross-sectional view of a second set of flow channel holes of an injection disk of a three-strike injector according to the present invention;

[0019] Figure 8 A bottom-view cross-sectional view of the third set of flow channel holes of the injection disk of a three-strike injector according to the present invention;

[0020] Fig. 9 A bottom-up cross-sectional view of a flow channel hole of an injection disk of a three-strike injector according to the present invention;

[0021] Fig.10 A three-dimensional diagram of an injection disk of a three-strike injector according to the present invention;

[0022] Fig.11 A bottom view of a three-strike injection hole group of an injection disk of a three-strike injector according to the present invention;

[0023] Fig.12 A bottom view of a partial view of a three-strike injection hole group of an injection disk of a three-strike injector according to the present invention;

[0024] Fig.13 A partial cross-sectional view of a three-strike injection hole group of an injection disk of a three-strike injector according to the present invention;

[0025] Fig.14 A bottom view of the fuel cooling hole of the injection disk of the three-shot injector of the present invention;

[0026] Fig.15 A bottom view of a partial view of a fuel cooling hole of an injection disk of a three-shot injector according to the present invention;

[0027] Fig.16 The present invention provides a bottom view of the injection disk of a triple-strike injector. DETAILED DESCRIPTION

[0028] The specific implementation of the present invention is described below in conjunction with the accompanying drawings;

[0029] The three-strike injector described in the present invention is used in a gas generator of a liquid rocket engine. The three-strike injector is located at the upper part of the gas generator, and a combustion chamber is arranged at the lower part. The bottom edge of the fuel shell (2) serves as the bottom connection part of the three-strike injector, and is welded to the top edge of the annular shell of the combustion chamber, forming a combustion chamber in which the space below the bottom of the injector is closed by the annular surface, so that the propellant injected by the three-strike injector can collide, atomize and burn in this space. In actual use, the fuel nozzle (3) of the three-strike injector is connected to the fuel tank through a pipeline, and the oxidant nozzle (4) is connected to the oxidant tank through a pipeline, thereby providing the three-strike injector with fuel and oxidant;

[0030] like Figure 1 As shown, the three-shot injector of the present invention comprises an injection disk (1), a fuel shell (2), a fuel nozzle (3) and an oxidant nozzle (4), wherein the middle portion of the injection disk (1) is conical, the interior of the cone is an oxidant chamber (13), an upper boss (11) is provided on the top of the injection disk (1), a circular hole (12) is opened in the center of the upper boss (11), and the circular hole (12) is connected to the oxidant chamber (13); A lower boss (14) is provided at the bottom, and regularly arranged flow channel holes (15), a three-shot injection hole group (16) and a fuel agent cooling hole (19) are provided in the lower boss (14); the three-shot injection hole group (16) includes two fuel agent holes (17) and an oxidant hole (18), wherein the fuel agent hole (17) is connected to the flow channel hole (15), and the oxidant hole (18) is connected to the oxidant chamber (13); the fuel agent shell (2) is connected to The upper boss (11) and the lower boss (14) of the injection disk (1) are fixedly connected by welding, and the fuel shell (2) and the conical side surface of the injection disk (1) form a fuel cavity (21) on the circumference. The fuel cooling holes (19) are located at the bottom edge area of ​​the lower boss (14) of the injection disk (1) and are evenly distributed along the circumference and are connected to the fuel cavity (21). A side hole (22) is opened on one side of the fuel shell (2) and is connected to the fuel cavity (21). The fuel nozzle (3) is connected by welding; the fuel nozzle (3) is cylindrical, and has a nozzle cavity (31) inside, which is connected to the fuel cavity (21); the top of the fuel shell (2) is designed with a circular groove (23), which is fixedly connected to the oxidant nozzle (4) by welding; the oxidant nozzle (4) is overall conical, and the nozzle cavity (41) inside is connected to the circular hole (12) of the injection disk (1) and the oxidant cavity (13);

[0031] like Figure 2The figure shows a front cross-sectional view of a fuel shell (2), wherein the fuel shell (2) is in an annular shape as a whole and has a side hole (22) on the side; a circular groove (23) and an upper circular hole (24) are provided at the upper end, and a lower circular hole (25) is provided at the lower end, wherein the upper circular hole (24) is fixedly connected to the upper boss (11) of the injection disk (1) by welding, and the lower circular hole (25) is fixedly connected to the lower boss (14) of the injection disk (1) by welding;

[0032] like Figure 3 The figure shows a front cross-sectional view of an injection disk (1), wherein the injection disk (1) is conical in the middle, an upper boss (11) is provided on the top, and a lower boss (14) is provided on the bottom, wherein the upper boss (11) and the lower boss (14) are respectively assembled with the upper circular hole (24) and the lower circular hole (25) of the fuel shell (2);

[0033] like Figure 4 As shown, it is a front cross-sectional view of the fuel agent nozzle (3), wherein the welding end of the fuel agent nozzle (3) is provided with a boss (32) which is in an assembly corresponding relationship with the side hole (22) of the fuel agent shell (2) and is fixedly connected by welding;

[0034] like Figure 5 As shown, it is a front cross-sectional view of the oxidant nozzle (4), wherein the welding end of the oxidant nozzle (4) is provided with a boss (42), which is in an assembly corresponding relationship with the circular groove (23) at the top of the fuel shell (2) and is fixedly connected by welding;

[0035] like Figure 6 The figure shows a bottom cross-sectional view of a first group of flow channel holes (15) of an injection disk (1). In this embodiment, the radius of the injection disk (1) is 125 mm. The first group of flow channel holes (15) are evenly distributed along the circumference at 8. The radial length of each flow channel hole (15) is 5 mm to 50 mm smaller than the radius of the injection disk (1) and is designed to be 100 mm. The aperture of each flow channel hole (15) is 10 mm. The first group of 8 flow channel holes (15) are designed along 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°, respectively. The four flow channel holes (15) along 45°, 135°, 225°, and 315° are interconnected, and the diameter of the connecting hole is 6 mm.

[0036] like Figure 7, which is a bottom-up cross-sectional view of the second group of flow channel holes (15) of the injection disk (1). In this embodiment, the second group of flow channel holes (15) are evenly distributed along the circumference of 8 holes. The radial length of each flow channel hole (15) is 25 mm to 75 mm smaller than the radius of the injection disk (1), and is designed to be 80 mm. The aperture of each flow channel hole (15) is 10 mm. The second group of 8 flow channel holes (15) are designed at 22.5°, 67.5°, 112.5°, 157.5°, 202.5°, 247.5°, 292.5°, and 337.5°, respectively.

[0037] like Figure 8 , which is a bottom-view cross-sectional view of the third group of flow channel holes (15) of the injection disk (1). In this embodiment, the third group of flow channel holes (15) are evenly distributed along the circumference of 16 holes. The radial length of each flow channel hole (15) is 50 mm to 100 mm smaller than the radius of the injection disk (1), and is designed to be 50 mm. The aperture of each flow channel hole (15) is 9 mm. The third group of 8 flow channel holes (15) are designed along 11.25°, 33.75°, 56.25°, 78.75°, 101.25°, 123.75°, 146.25°, 168.75°, 191.25°, 213.75°, 236.25°, 258.75°, 281.25°, 303.75°, 326.25°, and 348.75°, respectively.

[0038] like Fig. 9 As shown, Figure 6 , Figure 7 and Figure 8 A bottom-up cross-sectional view of the flow channel holes (15) on the combined injection disk (1), with a total of 32 flow channel holes (15) in three groups, and the flow channel holes (15) between groups are staggered and evenly distributed along the circumference;

[0039] like Fig.10 The figure shows a stereoscopic view of the injection disk (1), wherein the openings of the flow channel holes (15) are evenly distributed along the conical side of the injection disk (1). The fuel cooling holes (19) are evenly distributed along the circumference, and their openings are located in a spaced manner, with one portion located on the conical side of the injection disk (1) and one portion located within the opening edge of the flow channel holes (15);

[0040] like Fig.11 The figure shows a bottom view of a three-strike injection hole group (16) of an injection disk (1), wherein the bottom of the injection disk (1) is provided with 6 circles of three-strike injection hole groups (16) evenly distributed along the circumference, and the number of three-strike injection hole groups (16) included in each circle is 4, 8, 16, 16, 32, and 32 from the inside to the outside respectively; in order to ensure that the three-strike injection hole groups (16) are distributed relatively evenly on the bottom surface of the injection disk (1), the adjacent hole groups on the third circle and the fifth circle are arranged in an "eight" shape;

[0041] like Fig.12 , which is a partial bottom view of a three-shot injection hole group (16) of an injection disk (1). As can be seen from the figure, the three-shot injection hole group (16) includes two fuel holes (17) and one oxidant hole (18), wherein the two fuel holes (17) are located on both sides of the oxidant hole (18);

[0042] like Fig.13 As shown in FIG. 1 , a partial cross-sectional view of a three-strike injection hole group (16) of an injection disk (1) is shown. As can be seen from the figure, the one oxidant hole (18) is located between the two fuel holes (17), the axes of the two fuel holes (17) and the axis of the one oxidant hole (18) are at an angle of 5° to 85°, and the three axes intersect at one point. In this embodiment, the axes of the two fuel holes (17) and the axis of the one oxidant hole (18) are at an angle of 10°; the oxidant hole (18) is connected to the oxidant cavity (13), and the fuel hole (17) is connected to the flow channel hole (15); after multiple atomization and combustion tests, based on the combustion effect, it is determined that the optimal design diameters of the fuel hole (17) and the oxidant hole (18) are 1.1 mm and 1 mm, respectively;

[0043] like Fig.14 , which is a bottom view of the fuel agent cooling holes (19) of the injection disk (1). It can be seen from the figure that there are 64 fuel agent cooling holes (19) uniformly distributed along the circumference at the bottom edge area of ​​the lower boss (14) of the injection disk (1);

[0044] like Fig.15 As shown, it is a partial bottom view of the fuel agent cooling hole (19) of the injection disk (1). It can be seen from the figure that there is a certain distance between the fuel agent cooling hole (19) and the periphery of the lower boss (14) of the injection disk (1). After multiple atomization and combustion tests, according to the cooling effect of the fuel agent on the wall temperature, it is determined that the optimal design distance is 6 mm, and the diameter of the fuel agent cooling hole (19) is 1 mm;

[0045] like Fig.16 As shown, Fig. 9 , Fig.11 and Fig.14 A bottom view of the combined injection plate (1);

[0046] When the fuel is injected into the combustion chamber through the fuel hole (17) of the three-strike injection hole group (16), the oxidant is injected into the combustion chamber through the oxidant hole (18) of the three-strike injection hole group (16); two streams of fuel injected from the two fuel holes (17) of the three-strike injection hole group (16) and one stream of oxidant injected from the one oxidant hole (18) of the three-strike injection hole group (16) collide and atomize, mix and burn; at the same time, the fuel is directly injected into the combustion chamber through the fuel cooling hole (19), and the fuel evaporates at high temperature to form a side cooling layer, which not only reduces the wall temperature, but also enhances the mixing effect, thereby avoiding high temperature in the combustion chamber.

[0047] Practice has proved that the combustion efficiency of the gas generator using the injector of the present invention is at least 25% higher than that of the original gas generator, and can reach more than 95%; the bottom surface temperature of the injection disk is less than 60°C, and the cooling effect is good;

[0048] The above description is only a specific implementation mode of the present invention, but the protection of the present invention is not limited thereto. Any improvement without substantial change made by those skilled in the art without changing the principle and its application in the technical field of liquid rocket engine propellant gas generator should also be regarded as the protection scope of the present invention.

[0049] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in this field.

Claims

1. A three-strike injector, Features: The invention comprises an injection disk (1), a fuel shell (2), a fuel nozzle (3) and an oxidant nozzle (4), wherein the middle of the injection disk (1) is in a conical shape, the interior of the cone is an oxidant chamber (13), an upper boss (11) is provided on the top of the injection disk (1), a circular hole (12) is opened in the center of the upper boss (11), and the circular hole (12) is connected to the oxidant chamber (13); a lower boss (14) is provided on the bottom of the injection disk (1), and A regularly arranged flow channel hole (15), a three-shot injection hole group (16) and a fuel agent cooling hole (19) are provided in the lower boss (14); the three-shot injection hole group (16) includes two fuel agent holes (17) and one oxidant hole (18), wherein the fuel agent hole (17) is connected to the flow channel hole (15), and the oxidant hole (18) is connected to the oxidant chamber (13); the fuel agent housing (2) is connected to the upper boss of the injection disk (1). The upper and lower bosses (11) and the lower bosses (14) are fixedly connected by welding, and the fuel shell (2) and the conical side of the injection disk (1) form a fuel cavity (21) on the circumference, and the fuel cooling holes (19) are located in the bottom edge area of ​​the lower boss (14) of the injection disk (1) and are evenly distributed along the circumference and communicate with the fuel cavity (21); a side hole (22) is opened on one side of the fuel shell (2), and is fixedly connected to the fuel nozzle (3) by welding; the fuel nozzle (3) is cylindrical, and the interior is a first nozzle cavity (31), and the first nozzle cavity (31) is communicated with the fuel cavity (21); a circular groove (23) is provided on the top of the fuel shell (2), and is fixedly connected to the oxidant nozzle (4) by welding; the oxidant nozzle (4) is conical as a whole, and the second nozzle cavity (41) inside is communicated with the circular hole (12) of the injection disk (1) and the oxidant cavity (13).

2. The triple-strike injector according to claim 1, Features: The flow channel holes (15) are evenly distributed along the conical side surface of the injection disk (1) and are connected to the fuel chamber (21).

3. The triple-strike injector according to claim 1, Features: There are three groups of flow channel holes (15), each group is evenly distributed along the circumference, wherein the length of the first group of flow channel holes (15) along the radial direction is 5 mm to 50 mm smaller than the radius of the injection disk (1); the length of the second group of flow channel holes (15) along the radial direction is 25 mm to 75 mm smaller than the radius of the injection disk (1); the length of the third group of flow channel holes (15) along the radial direction is 50 mm to 100 mm smaller than the radius of the injection disk (1); the flow channel holes (15) evenly distributed in the form of intervals in the first group of flow channel holes (15) or the second group of flow channel holes (15) are interconnected in the radial direction.

4. The triple-strike injector according to claim 1, Features: The one oxidant hole (18) is located in the middle of the two fuel holes (17), the axes of the two fuel holes (17) form an angle of 5° to 85° with the axis of the one oxidant hole (18), and the three axes intersect at one point.

5. The triple-strike injector according to claim 1, Features: The fuel shell (2) is in the shape of a ring as a whole, with a side hole (22) opened on the side; a circular groove (23) and an upper circular hole (24) are provided at the upper end, and a lower circular hole (25) is provided at the lower end, wherein the upper circular hole (24) is fixedly connected to the upper boss (11) of the injection disk (1) by welding, and the lower circular hole (25) is fixedly connected to the lower boss (14) of the injection disk (1) by welding.

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