High-pressure large-flow pre-combustion chamber structure of afterburning cycle engine

Abstract

The invention discloses a high-pressure large-flow pre-combustion chamber structure of an afterburning cycle engine, and belongs to the technical field of machinery. The injector is of a three-cavity structure. And the uppermost part far away from the combustion chamber is the oxidant cavity, the oxidant cavity adopts a single-side inlet, and the flow of an oxidant in the oxidant cavity is more uniform through the flow equalizing plate in the oxidant cavity, so that the flow and the mixing ratio among the nozzles of the injector are uniform. A fuel secondary injection cavity is arranged at the lowermost part close to the combustion chamber, and the fuel subjected to secondary injection enters the combustion chamber through a plurality of self-impact injection holes in the injection panel. A fuel primary injection cavity is formed in the middle, and fuel injected for the first time enters the combustion chamber through a fuel nozzle. Fuel is divided into two independent cavities, mutual interference between the fuel in different injection modes is avoided, and stable combustion of the injector is facilitated.

Description

Technical Field

[0001] The invention relates to a high-pressure and high-flow pre-combustion chamber structure of a supplementary combustion cycle engine, belonging to the technical field of machinery. Background Art

[0002] As an important component of the regenerative cycle liquid rocket engine, the precombustion chamber is used to produce combustion gas with uniform temperature to work on the turbine. The turbine fluid then directly enters the thrust chamber and undergoes regenerative combustion in the combustion chamber. The precombustion chamber of a high-thrust liquid rocket engine is characterized by high chamber pressure, large flow, and high fuel richness. Under high fuel richness conditions, since the propellant equivalence ratio of the precombustion chamber seriously deviates from the chemical equivalence ratio, it is difficult to organize stable combustion and unstable combustion is very likely to occur. In addition, the large flow rate also has an adverse effect on the nozzle atomization, which directly affects the stable combustion of the precombustion chamber. At present, unstable combustion has occurred in the precombustion chamber of a high-thrust rocket engine during testing. Summary of the invention

[0003] The technical problem solved by the present invention is: to overcome the shortcomings of the prior art, to provide a high-pressure and high-flow precombustion chamber structure for a supplementary combustion cycle engine, to solve the problem of difficulty in organizing combustion under high chamber pressure, high flow and high-rich fuel conditions, to achieve efficient and stable combustion in the precombustion chamber, and to produce combustion gas with uniform temperature.

[0004] The technical solution of the present invention is: a high-pressure and high-flow pre-combustion chamber structure of a supplementary combustion cycle engine, comprising:

[0005] The fuel collector shell is a spherical structure with two openings at both ends, wherein the upper end is connected to the two bottoms, and the lower end is connected to the body. The cavity between the three is the fuel collector cavity, and a fuel inlet is provided on the side of the shell;

[0006] The top cover is provided with an oxidant inlet and an igniter inlet, and a flow equalizing plate is provided on the inner wall for the oxidant to flow through, and the other end of the igniter inlet is connected to the combustion chamber;

[0007] The second bottom is installed on the outer end of the top cover, including the second bottom outer ends, the upper support wall, the injection panel and the side support wall. The upper support wall, the injection panel and the side support wall constitute a fuel chamber; the fuel chamber includes a separated primary fuel injection chamber and a secondary fuel injection chamber; the second bottom outer ends are located at the connection between the upper support wall and the side support wall, and the fuel collector shell is installed respectively; the upper support wall and the top cover form an oxidant cavity; the injection panel is connected to the body, and a plurality of secondary fuel injection holes are arranged on it; the side support wall is provided with a primary fuel inlet and a secondary fuel inlet; a plurality of injection units are arranged in the fuel cavity Each injection unit penetrates the upper support wall and the injection panel, and an oxidant nozzle is provided at the place where the upper support wall is penetrated, so that the oxidant can enter the internal flow channel of the injection unit; the injection unit is provided with a fuel nozzle at the part of the primary fuel injection chamber; the first part of the fuel flows into the fuel nozzle through the primary fuel inlet, and is mixed and burned with the oxidant flowing through the oxidant nozzle at the flame nozzle where the injection unit penetrates the injection panel to form a flame; the second part of the fuel flows into the secondary fuel injection chamber through the secondary fuel inlet, and is sprayed into the combustion chamber from the secondary fuel injection hole on the injection panel, and is mixed with the flame at the flame nozzle to reduce the gas temperature;

[0008] The body has a combustion chamber inside and is connected to the fuel collector shell on the outside to form a fuel collection cavity for fuel input; the side wall of the body is provided with a tertiary fuel inlet, and the third part flows through the tertiary fuel inlet and is discharged into the combustion chamber to mix with the fuel gas.

[0009] Furthermore, a plurality of rectangular cooling channels are arranged on the inner wall of the body for the third part of the fuel to flow through.

[0010] Furthermore, the cooling channel inlet is connected to the fuel collector cavity through multiple tertiary fuel inlets, and the outlet is connected to the combustion chamber. The third part flows through the tertiary fuel inlets into the cooling channel, cools the inner wall of the body, and is discharged into the combustion chamber to mix with the fuel gas.

[0011] Furthermore, the body is cylindrical.

[0012] Furthermore, the secondary fuel injection holes on the injection panel are arranged in pairs and used in pairs.

[0013] Furthermore, the paired secondary fuel injection holes are arranged in an inverted eight shape and converge toward the combustion chamber.

[0014] Furthermore, the angle between the secondary fuel injection hole and the axis of the combustion chamber is 10° to 20°.

[0015] Furthermore, the oxidant nozzle and the fuel nozzle are coaxial nozzles, and the nozzle type is a centrifugal nozzle, a straight-flow nozzle or an annular gap nozzle. The flow rates flowing through the oxidant nozzle and the fuel nozzle are designed according to an equivalent ratio of 1 to 2.

[0016] Furthermore, the oxidant nozzle outlet is retracted relative to the fuel nozzle by a distance of 1 to 1.5 times the diameter of the oxidant nozzle.

[0017] Furthermore, the spherical diameter of the fuel collector is large enough to cover the rectangular cooling channel on the inner wall of the body.

[0018] The advantages of the present invention compared with the prior art are:

[0019] (1) The present invention solves the problem that it is difficult to organize efficient and stable combustion under high-flow and high-rich combustion conditions. To this end, the fuel is divided into three parts: the first part of the fuel burns with the oxidant at an equivalent ratio of 1 to 2 near the nozzle outlet to form a high-temperature stable flame; the second part of the fuel is formed through the injection holes on the injection panel, which are self-struck in pairs to form uniform droplets, and are mixed with the high-temperature flame near the nozzle outlet to form a combustion gas with uniform temperature; the third part of the fuel enters the combustion chamber through the cooling channel on the inner wall of the body to cool and protect the inner wall of the body.

[0020] (2) The present invention relates to a high-pressure, high-flow pre-combustion chamber structure of a supplemental combustion cycle engine, in which the injector adopts a three-chamber structure. The uppermost chamber, farthest from the combustion chamber, is the oxidant chamber, which adopts a single-side inlet, and the flow of the oxidant in the chamber is made more uniform by the flow equalizer in the oxidant chamber, which is beneficial to the uniformity of the flow rate and mixing ratio between the nozzles of the injector. The lowermost chamber, close to the combustion chamber, is the secondary fuel injection chamber, and the secondary injected fuel enters the combustion chamber through a plurality of self-impact injection holes on the injection panel. The middle chamber is the primary fuel injection chamber, and the primary injected fuel enters the combustion chamber through the fuel nozzle. The fuel is divided into two independent chambers to avoid mutual interference between fuels of different injection methods, which is beneficial to the stable combustion of the injector.

[0021] (3) The present invention relates to a high-pressure and high-flow pre-combustion chamber structure of a supplementary combustion cycle engine, wherein the nozzle adopts a coaxial nozzle structure. The inner nozzle is an oxidant nozzle, which can be a centrifugal nozzle or a direct current nozzle; the outer nozzle is a fuel nozzle, which can be a centrifugal nozzle or an annular gap nozzle. To ensure the flame stability at the nozzle outlet, the inner nozzle outlet should be retracted by 1 to 1.5 times the inner nozzle diameter compared to the outer nozzle. If the inner nozzle is retracted too small, it is not conducive to the flame stability at the nozzle outlet; if the retracted distance is too large, it may cause nozzle ablation.

[0022] (4) The present invention relates to a high-pressure and high-flow pre-combustion chamber structure of a supplementary combustion cycle engine, in which the fuel collector shell adopts a spherical structure. The spherical structure is conducive to withstanding high pressure and can minimize weight under the same pressure resistance conditions. In addition, the spherical structure of the fuel collector shell wraps the pre-combustion chamber part so that the inner wall of this part can only withstand the lower pressure difference between the fuel and the combustion chamber, thereby improving the working environment of the body and reducing the mechanical performance requirements of the body material.

[0023] (5) The present invention relates to a high-pressure, high-flow pre-combustion chamber structure of a regenerative cycle engine, the body of which adopts a cylindrical structure with a cooling channel. A small amount of fuel is used to cool the body, which can effectively prevent the inner wall of the body from being ablated. The fuel after cooling the body is discharged into the combustion chamber through the outlet of the cooling channel, and after mixing with the fuel gas, it drives the turbine to do work. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0025] Figure 1 This is a schematic diagram of the pre-combustion chamber of the patent of this invention.

[0026] Figure 2 This is a schematic diagram of the pre-combustion chamber injector of the patent of this invention.

[0027] Figure 3 This is a schematic diagram of the pre-combustion chamber injection panel of the patent of this invention. DETAILED DESCRIPTION

[0028] In order to better understand the above technical scheme, the technical scheme of the present invention is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical scheme of the present invention, rather than limitations on the technical scheme of the present invention. In the absence of conflict, the embodiments of the present invention and the technical features in the embodiments can be combined with each other.

[0029] The following is a further detailed description of a high-pressure and high-flow pre-combustion chamber structure of a supplementary combustion cycle engine provided by an embodiment of the present invention in conjunction with the accompanying drawings of the specification. The specific implementation method may include:

[0030] The fuel collector shell 3 is a spherical structure with two ends open, wherein the upper end is connected to the second bottom 2, and the lower end is connected to the body 4. The cavity between the three is the fuel collector cavity 10, and a fuel inlet is provided on the side of the shell;

[0031] The top cover 1 is provided with an oxidant inlet and an igniter inlet, and a flow equalizing plate 11 is provided on the inner wall for the oxidant to flow through, and the other end of the igniter inlet is connected to the combustion chamber 9;

[0032] The second bottom 2 is installed on the outer end of the top cover 1, including the second bottom outer end, the upper support wall, the injection panel 13 and the side support wall. The upper support wall, the injection panel 13 and the side support wall constitute a fuel chamber; the fuel chamber includes a separated fuel primary injection chamber 7 and a fuel secondary injection chamber 8; the second bottom outer end is located at the connection between the upper support wall and the side support wall, and the fuel collector shell 3 is installed respectively; the upper support wall and the top cover 1 form an oxidant chamber; the injection panel 13 is connected to the body 4, and a plurality of fuel secondary injection holes 17 are arranged on it; the side support wall is provided with a fuel primary inlet 14 and a fuel secondary inlet 15; a plurality of injection units are arranged in the fuel chamber Each injection unit penetrates the upper support wall and the injection panel 13, and an oxidant nozzle 5 is provided at the place where the upper support wall is penetrated, so that the oxidant can enter the internal flow channel of the injection unit; the injection unit is provided with a fuel nozzle 6 at the part located in the primary fuel injection chamber 7; the first part of the fuel flows into the fuel nozzle 6 through the primary fuel inlet 14, and is mixed and burned with the oxidant flowing through the oxidant nozzle 5 at the flame nozzle where the injection unit penetrates the injection panel 13 to form a flame; the second part of the fuel flows into the secondary fuel injection chamber 8 through the secondary fuel inlet 15, and is sprayed into the combustion chamber 9 from the secondary fuel injection hole 17 on the injection panel 13, and is mixed with the flame at the flame nozzle to reduce the gas temperature;

[0033] The body 4 has a combustion chamber 9 inside and is connected to the fuel collector shell 3 on the outside to form a fuel collection cavity for fuel input; a tertiary fuel inlet 16 is provided on the side wall of the body 4, and the third part flows through the tertiary fuel inlet 16 and is discharged into the combustion chamber 9 to be mixed with the fuel gas.

[0034] In the solution provided in the embodiment of the present invention, Figure 1 As shown, it includes a top cover 1, a second bottom 2, a fuel collector shell 3, a body 4, multiple oxidant nozzles 5, multiple fuel nozzles 6, and an injection panel 13. The top cover 1, the second bottom 2, the multiple oxidant nozzles 5, the multiple fuel nozzles 6, and the injection panel 13 are formed into an injector by welding or 3D printing. The injector is connected to the fuel collector shell 3 and the body 4 by welding. Figure 2 and Figure 3 As shown, the injection panel 13 is provided with a plurality of secondary fuel injection holes 17 , which are cylindrical through holes with an angle of 10° to 20° with the axis of the combustion chamber. The secondary fuel injection holes 17 form a pair and work in pairs.

[0035] The top cover 1 and the second bottom 2 form an oxidant chamber 12, and the equalizing plate 11 located on the top cover 1 divides the oxidant chamber into two parts, the upper part is connected to the oxidant inlet, and the lower part is connected to the oxidant nozzle 5. The structure of the equalizing plate 11 is a thin plate with multiple circles of circular through holes, which plays a role in rectifying the flow of the oxidant. The oxidant enters the upper part of the oxidant chamber from the oxidant inlet, enters the lower part of the oxidant chamber after being rectified by the equalizing plate 11, and is sprayed into the combustion chamber 9 through multiple oxidant nozzles 5, and burns with the fuel near the outlet of the oxidant nozzle.

[0036] The fuel enters the fuel collector chamber 10 from the fuel inlet. After deceleration and rectification in the fuel collector chamber 10, it is divided into three parts. The first part of the fuel enters the fuel primary injection chamber 7 through the fuel primary inlet 14, flows through multiple fuel nozzles 6 into the combustion chamber 9, and burns with the oxidant sprayed from the oxidant nozzle 5 near the nozzle outlet to form a high-temperature stable flame. The second part of the fuel flows through the fuel secondary inlet 15 into the fuel secondary injection chamber 8, and is sprayed into the combustion chamber 9 through multiple pairs of fuel secondary injection holes 17 on the injection panel 13, and is mixed with the high-temperature flame near the nozzle outlet to cool the fuel gas and form a fuel gas with uniform temperature that meets the requirements. The third part of the fuel flows through the fuel tertiary inlet 16 into the body cooling channel, cools the inner wall of the body, and then enters the combustion chamber 9 again from the cooling channel outlet to mix with the fuel gas. Finally, the fuel gas flows out through the fuel outlet to drive the turbine or other devices to do work.

[0037] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0038] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

[0039] The contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

Claims

1. A high-pressure and high-flow pre-combustion chamber structure for a supplementary combustion cycle engine, characterized in that: include: The fuel collector shell (3) is a spherical structure with two ends open, wherein the upper end is connected to the two bottoms (2), and the lower end is connected to the body (4). The cavity between the three is the fuel collector cavity (10), and a fuel inlet is provided on the side of the shell; The top cover (1) is provided with an oxidant inlet and an igniter inlet, and a flow equalizing plate (11) is provided on the inner wall for the oxidant to flow through, and the other end of the igniter inlet is connected to the combustion chamber (9); The second bottom (2) is installed at the outer end of the top cover (1), including the outer ends of the second bottom, the upper support wall, the injection panel (13) and the side support wall, the upper support wall, the injection panel (13) and the side support wall constitute a fuel chamber; the fuel chamber includes a separated primary fuel injection chamber (7) and a secondary fuel injection chamber (8); the outer ends of the second bottom are located at the connection between the upper support wall and the side support wall, and the fuel collector shell (3) is installed respectively; the upper support wall and the top cover (1) form an oxidant chamber; the injection panel (13) is connected to the body (4), and a plurality of secondary fuel injection holes (17) are provided on it; the side support wall is provided with a primary fuel inlet (14) and a secondary fuel inlet (15); a plurality of injection units are provided in the fuel chamber Each injection unit penetrates the upper support wall and the injection panel (13), and an oxidant nozzle (5) is provided at the place where the upper support wall is penetrated, so that the oxidant can enter the internal flow channel of the injection unit; the injection unit is provided with a fuel nozzle (6) at the part located in the primary fuel injection chamber (7); the first part of the fuel flows through the primary fuel inlet (14) and enters the fuel nozzle (6), and is mixed with the oxidant flowing through the oxidant nozzle (5) and burns at the flame nozzle where the injection unit penetrates the injection panel (13) to form a flame; the second part of the fuel flows through the secondary fuel inlet (15) and enters the secondary fuel injection chamber (8), and is sprayed into the combustion chamber (9) from the secondary fuel injection hole (17) on the injection panel (13), and is mixed with the flame at the flame nozzle to reduce the gas temperature; The body (4) has a combustion chamber (9) inside and is connected to a fuel collector shell (3) on the outside to form a fuel collection cavity for inputting fuel. A tertiary fuel inlet (16) is provided on the side wall of the body (4), and the third part flows through the tertiary fuel inlet (16) and is discharged into the combustion chamber (9) to be mixed with the fuel gas.

2. A high-pressure and high-flow pre-combustion chamber structure for a supplementary combustion cycle engine according to claim 1, characterized in that: A plurality of rectangular cooling channels are arranged on the inner wall of the body (4) for the third part of the fuel to flow through.

3. A high-pressure and high-flow pre-combustion chamber structure for a supplementary combustion cycle engine according to claim 2, characterized in that: The inlet of the cooling channel is connected to the fuel collector cavity (10) through a plurality of tertiary fuel inlets (16), and the outlet is connected to the combustion chamber (9). The third part flows through the tertiary fuel inlet (16) into the cooling channel, cools the inner wall of the body (4), and is then discharged into the combustion chamber (9) to be mixed with the fuel gas.

4. A high-pressure and high-flow pre-combustion chamber structure for a supplementary combustion cycle engine according to claim 1, characterized in that: The body (4) is cylindrical.

5. The high-pressure and high-flow pre-combustion chamber structure of a supplementary combustion cycle engine according to claim 1, characterized in that: The secondary fuel injection holes (17) on the injection panel (13) are arranged in pairs and are used in pairs.

6. A high-pressure and high-flow pre-combustion chamber structure for a supplementary combustion cycle engine according to claim 5, characterized in that: The paired secondary fuel injection holes (17) are arranged in an inverted eight and converge toward the combustion chamber (9).

7. A high-pressure and high-flow pre-combustion chamber structure for a supplementary combustion cycle engine according to claim 6, characterized in that: The angle between the secondary fuel injection hole (17) and the axis of the combustion chamber (9) is 10° to 20°.

8. The high-pressure and high-flow pre-combustion chamber structure of a supplementary combustion cycle engine according to claim 1, characterized in that: The oxidant nozzle (5) and the fuel nozzle (6) are coaxial nozzles, and the nozzle type is a centrifugal nozzle, a straight-flow nozzle or an annular gap nozzle. The flow rates flowing through the oxidant nozzle (5) and the fuel nozzle (6) are designed according to an equivalent ratio of 1 to 2.

9. A high-pressure and high-flow pre-combustion chamber structure for a supplementary combustion cycle engine according to claim 1, characterized in that: The outlet of the oxidant nozzle (5) is retracted relative to the fuel nozzle (6) by a distance of 1 to 1.5 times the diameter of the oxidant nozzle.

10. A high-pressure and high-flow pre-combustion chamber structure for a supplementary combustion cycle engine according to claim 1, characterized in that: The spherical diameter of the fuel collector (3) is large enough to cover the rectangular cooling channel on the inner wall of the body (4).

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