A high-pressure and high-flow precombustion chamber structure for a supplementary combustion cycle engine

Abstract

A high-pressure, high-flow pre-combustion chamber structure for a supplementary combustion cycle engine belongs to the field of mechanical technology. The injector of the present invention adopts a three-chamber structure. The uppermost chamber away from the combustion chamber is the oxidizer chamber, which adopts a single-side inlet, and the equalizing plate in the oxidizer chamber makes the flow of the oxidizer in the chamber more uniform, which is beneficial to the uniformity of the flow 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 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.

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 a regenerative liquid rocket engine, the preburner's function is to produce combustion gases of uniform temperature to perform work on the turbine. The turbine fluid then enters the thrust chamber directly for regenerative combustion in the combustion chamber. The preburner of a high-thrust liquid rocket engine is characterized by high chamber pressure, high flow rate, and high fuel richness. Under high fuel richness conditions, the propellant equivalence ratio in the preburner deviates significantly from the chemical equivalence ratio, making stable combustion difficult to achieve and making unstable combustion very likely to occur. Furthermore, the high flow rate adversely affects nozzle atomization, directly impacting the stable combustion in the preburner. Currently, unstable combustion has occurred in preburner tests of high-thrust rocket engines. Summary of the Invention

[0003] The technical problem solved by the present invention is: to overcome the shortcomings of the existing technology, provide a high-pressure and high-flow precombustion chamber structure for a supplementary combustion cycle engine, solve the problem of difficulty in organizing combustion under high chamber pressure, high flow and high-rich fuel conditions, realize efficient and stable combustion in the precombustion chamber, and generate 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 manifold housing is a spherical structure with openings at both ends. 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 manifold cavity. A fuel inlet is provided on the side of the housing.

[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. 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 end, 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 fuel primary injection chamber and a fuel secondary injection chamber; 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 is installed respectively; the upper support wall and the top cover form an oxidizer chamber; the injection panel is connected to the body, and is provided with a number of fuel secondary injection holes; the side support wall is provided with a fuel primary inlet and a fuel secondary inlet; the fuel chamber is provided with a number of injection units 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 fuel primary injection chamber; the first part of the fuel flows into the fuel nozzle through the fuel primary inlet, and is mixed 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 fuel secondary injection chamber through the fuel secondary inlet, and is injected into the combustion chamber from the fuel secondary 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 provided on the inner wall of the body for the circulation of the third portion of fuel.

[0010] Furthermore, the inlet of the cooling channel 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 rate flowing through the oxidant nozzle and the fuel nozzle is designed according to an equivalence 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 diameter of the fuel collector is large enough to cover the rectangular cooling channel on the inner wall of the fuel collector.

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

[0019] (1) The present invention solves the problem of difficulty in organizing 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 oxidizer 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 by self-strike through the injection holes on the injection panel to form uniform droplets, which 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 supplementary combustion cycle engine, in which the injector adopts a three-chamber structure. The uppermost chamber, farthest from the combustion chamber, is the oxidizer chamber, which adopts a single-side inlet, and the equalizing plate in the oxidizer chamber makes the flow of the oxidizer in the chamber more uniform, which is beneficial to the uniformity of the flow and mixing ratio between the nozzles of the injector. The lowermost chamber, close to the combustion chamber, is the fuel secondary injection chamber, and the fuel for the secondary injection enters the combustion chamber through a plurality of self-impact injection holes on the injection panel. The middle chamber is the fuel primary injection chamber, and the fuel for the primary injection 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, high-flow pre-combustion chamber structure for a supplementary combustion cycle engine, wherein the nozzle adopts a coaxial nozzle structure. The inner nozzle is an oxidizer nozzle, which can be a centrifugal nozzle or a straight-flow 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 retracts too little, it will be detrimental 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, high-flow pre-combustion chamber structure for a regenerative cycle engine, wherein the fuel collector shell adopts a spherical structure. The spherical structure is advantageous for withstanding high pressure and can minimize weight under the same pressure resistance conditions. In addition, the spherical fuel collector shell wraps around a portion of the pre-combustion chamber body, so that the inner wall of this portion 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 precombustion chamber structure for a regenerative cycle engine. The engine body is a cylindrical structure with cooling channels. Using a small amount of fuel to cool the engine body effectively prevents ablation of the engine body's inner wall. The fuel, after cooling the engine body, is discharged into the combustion chamber through the cooling channel outlet and mixed with the combustion gas to drive the turbine to produce work. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the 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 solution, the technical solution of the present invention is described in detail below with reference to 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 solution of the present invention, rather than limitations on the technical solution 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, high-flow pre-combustion chamber structure for a supplementary combustion cycle engine provided by an embodiment of the present invention in conjunction with the accompanying drawings. Specific implementation methods may include:

[0030] The fuel manifold housing 3 is a spherical structure with openings at both ends. The upper end is connected to the second base 2, and the lower end is connected to the body 4. The cavity between the three is the fuel manifold chamber 10. A fuel inlet is provided on the side of the housing.

[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. 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 oxidizer chamber; the injection panel 13 is connected to the body 4, and is provided with a number of fuel secondary injection holes 17; the side support wall is provided with a fuel primary inlet 14 and a fuel secondary inlet 15; the fuel chamber is provided with a number of injection units 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 of the fuel primary injection chamber 7; the first part of the fuel flows into the fuel nozzle 6 through the fuel primary inlet 14, and is mixed with the oxidant flowing through the oxidant nozzle 5 and burned 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 fuel secondary injection chamber 8 through the fuel secondary inlet 15, and is injected into the combustion chamber 9 from the fuel secondary 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 mix 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, two bottoms 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, two bottoms 2, multiple oxidant nozzles 5, multiple fuel nozzles 6, and an 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 . The secondary fuel injection holes 17 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 oxidant chamber 12 is formed between the top cover 1 and the second bottom 2. A flow equalizer plate 11 located on the top cover 1 divides the oxidant chamber into two parts, the upper half of which is connected to the oxidant inlet, and the lower half is connected to the oxidant nozzle 5. The flow equalizer plate 11 is a thin plate with multiple circular through-holes, which serves to rectify the oxidant flow. The oxidant enters the upper half of the oxidant chamber from the oxidant inlet, is rectified by the flow equalizer plate 11, and enters the lower half of the oxidant chamber. It is then sprayed into the combustion chamber 9 through the multiple oxidant nozzles 5, where it burns with the fuel near the oxidant nozzle outlet.

[0036] The fuel enters the fuel manifold chamber 10 from the fuel inlet. After deceleration and rectification in the fuel manifold 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 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 document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

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

[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 plate (11) is provided on the inner wall for the oxidant to flow through. 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, and the upper support wall, the injection panel (13) and the side support wall constitute a fuel cavity; the fuel cavity includes a separated fuel primary injection cavity (7) and a fuel secondary injection cavity (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 cavity; the injection panel (13) is connected to the body (4), and is provided with a plurality of fuel secondary injection holes (17); the side support wall is provided with a fuel primary inlet (14) and a fuel secondary inlet (15); the fuel cavity is provided with a plurality of injection units Each injection unit passes through the upper support wall and the injection panel (13), and an oxidant nozzle (5) is provided at the upper support wall to allow the oxidant to enter the internal flow channel of the injection unit; the injection unit is provided with a fuel nozzle (6) at the fuel primary injection chamber (7); the first part of the fuel flows through the fuel primary inlet (14) into the fuel nozzle (6), and is mixed with the oxidant flowing through the oxidant nozzle (5) at the flame nozzle of the injection unit passing through the injection panel (13) to burn and form a flame; the second part of the fuel flows through the fuel secondary inlet (15) into the fuel secondary injection chamber (8), and is injected into the combustion chamber (9) from the fuel secondary 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 fuel input; a fuel tertiary inlet (16) is provided on the side wall of the body (4), and the third part flows through the fuel tertiary 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 provided on the inner wall of the body (4) for the circulation of the third portion of fuel.

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

4. The high-pressure and high-flow pre-combustion chamber structure of 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 used in pairs.

6. The high-pressure and high-flow pre-combustion chamber structure of 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 pattern and converge toward the combustion chamber (9).

7. The high-pressure and high-flow pre-combustion chamber structure of 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 form is a centrifugal nozzle, a straight-flow nozzle or an annular gap nozzle. The flow rate flowing through the oxidant nozzle (5) and the fuel nozzle (6) is designed according to an equivalent ratio of 1 to 2.

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

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