A liquid fuel engine thrust chamber pintle head regenerative cooling structure

Abstract

The present application relates to the technical field of aerospace engine, in particular to a liquid fuel engine thrust chamber needle bolt head regenerative cooling structure, comprising: a thrust chamber and a needle injection injector, the injector shell of the needle injection injector is arranged in the thrust chamber from the top of the thrust chamber, and the injector shell is located in the thrust chamber, at least one week main injection hole is arranged on the radial of the injector shell, the annular gap is formed between the injector shell and the top shell of the thrust chamber, and the end of the injector shell is provided with an inner recess structure in the thrust chamber; The first cooling flow channel and the second cooling flow channel are arranged in the injector shell above and below the main injection hole, and the outlet of the second cooling flow channel is connected with the rotational flow tangential hole; wherein, the liquid propellant in the propellant combination is injected into the injector shell, and the annular gap between the injector shell and the top shell of the thrust chamber is used for injecting another propellant in the propellant combination. The present application improves the combustion efficiency of the thrust chamber, and improves the specific impulse and the thrust-to-weight ratio of the engine.

Description

Technical Field

[0001] This invention relates to the field of aerospace engine technology, specifically to a regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber. Background Technology

[0002] Currently, needle injectors are widely used in liquid fuel engines, ranging from 22N thrust N2O4 / hydrazine engines to 2900kN thrust LH2 / LOX engines.

[0003] Needle-plug injectors require a certain jump distance between radial and axial injection, so the needle plug head needs to extend a certain length into the combustion chamber. Near the needle plug head, multiple vortices and backflow zones are formed due to the propellant jet, resulting in a complex and harsh thermal environment, which places certain requirements on the thermal protection of the needle plug head.

[0004] However, the usual method for heat protection of the needle plug is to set several DC auxiliary nozzles on the wall surface. The DC auxiliary nozzles lose a certain flow of propellant to push away the high-temperature gas and adjust the mixing ratio in the near-wall zone to reduce the gas temperature in the near-wall zone. This method will cause a certain degree of reduction in combustion efficiency.

[0005] Therefore, there is a need to provide a regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber to solve the above problems. Summary of the Invention

[0006] This invention provides a regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber to solve existing problems.

[0007] The first aspect of the present invention provides a regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber. This structure comprises: a thrust chamber and a needle plug injector; the injector housing of the needle plug injector extends from the top of the thrust chamber into the thrust chamber; the injector housing is radially provided with at least one main injection hole within the thrust chamber; an annular gap is formed between the injector housing and the top housing of the thrust chamber; and a concave structure is provided at the end of the injector housing located within the thrust chamber; a first cooling channel is formed within the injector housing above the main injection hole, running in a direction opposite to the concave structure, with the outlet of the first cooling channel facing the interior of the thrust chamber housing; a second cooling channel is formed within the injector housing below the main injection hole, running in a direction facing the injector housing; the outlet of the second cooling channel extends into the concave structure; and the outlet of the second cooling channel communicates with a swirling tangential hole provided on the concave wall of the concave structure.

[0008] The injector housing is used to inject liquid propellant into the propellant combination, while the circumferential gap between the injector housing and the top housing of the thrust chamber is used to inject another type of propellant into the propellant combination.

[0009] A further technical solution of the present invention is that the propellant combination adopts one of the following propellant combinations: liquid oxygen and kerosene, hydrogen peroxide and hydrocarbons, nitrogen oxides and hydrocarbons, liquid oxygen and liquid hydrogen, and liquid oxygen and methane.

[0010] In a further technical solution of the present invention, an annular boss is radially provided on the injector housing located in the annular gap; the annular boss has a first outlet flow channel with the outlet facing the inside of the thrust chamber, a first intermediate flow channel is provided in the injector housing between the main injection hole and the top of the annular boss, and a first inlet flow channel is provided on the inner wall of the injector housing above the main injection hole, and the first inlet flow channel is connected to the first outlet flow channel through the first intermediate flow channel to form a first cooling flow channel.

[0011] A further technical solution of the present invention is that after the liquid propellant enters through the first inlet channel of the first cooling channel and is discharged through the first outlet channel, a cooling oil film is formed between the liquid propellant and the outer wall of the injector housing.

[0012] A further technical solution of the present invention includes a concave structure comprising a boss provided on the bottom end face of the injector housing and a groove provided on the outer end face of the injector housing, wherein the groove is formed on the end face of the boss facing the thrust chamber and a swirl tangential hole is provided on the groove surface.

[0013] A further technical solution of the present invention includes a second inlet channel on the inner wall of the injector housing below the main injection hole, a second intermediate channel in the injector housing along the direction opposite to the main injection hole, a connecting hole in the radial direction of the end face of the injector housing, and a boss channel in the boss along the axial direction of the boss. The second inlet channel is sequentially connected to the second intermediate channel, the connecting hole, the boss channel, and the swirl tangential hole provided on the inner wall of the groove.

[0014] A second aspect of the present invention provides a liquid fuel engine, comprising: a regenerative cooling structure for the thrust chamber needle plug of a liquid fuel engine provided in the first aspect of the present invention.

[0015] A third aspect of the present invention provides a spacecraft comprising: a liquid fuel engine provided in the second aspect of the present invention.

[0016] The beneficial effects of this invention are:

[0017] This invention provides a concave structure on the end face of the injector housing below the main injection orifice. A first cooling channel, directed away from the concave structure, is formed within the injector housing above the main injection orifice, with its outlet facing the interior of the thrust chamber. A second cooling channel, directed towards the injector housing, is formed within the injector housing below the main injection orifice, with its outlet extending into the concave structure. The outlet of the second cooling channel communicates with a swirling tangential hole on the concave wall of the concave structure. This avoids the need for multiple rows of auxiliary nozzles on the injector housing below the main injection orifice, as required by traditional techniques. Heat dissipation is achieved by incorporating swirling tangential orifices (i.e., auxiliary nozzles in the prior art) and a second cooling channel near the end face (needle head) of the injector housing to adjust the near-wall mixing ratio. Cooling is achieved through these swirling tangential orifices and the second cooling channel. Compared to the number of direct-flow auxiliary nozzles in the prior art, the present invention uses fewer swirling tangential orifices, and these orifices spray atomized propellant, thus reducing propellant waste. Simultaneously, the present invention increases the flow rate of the main injection orifice on the injector housing of the needle-plug injector, achieving more efficient atomization and combustion, improving the combustion efficiency of the thrust chamber, and increasing the engine's specific impulse and thrust-to-weight ratio. In other words, compared to conventional thrust chamber needle heads, the present invention allows more flow to be used for more efficient atomization and combustion in the main injection orifice. Compared to direct-flow auxiliary nozzles, the present invention specifically uses regenerative cooling and liquid film cooling across the entire needle head wall, and centrifugal auxiliary nozzles on the lower end face of the needle head to adjust the near-wall mixing ratio, resulting in higher cooling efficiency for the needle head. Since the structure of this invention is completed by 3D printing, the active cooling channel and liquid film channel structure layout of the thrust chamber needle head can be more reasonable and compact. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of a regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber according to the present invention.

[0020] In the figure: 1. Thrust chamber; 2. Injector housing; 21. First cooling channel; 22. Concave structure; 23. Swirl tangential hole; 24. Second cooling channel. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] An embodiment of the regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber according to the present invention, such as... Figure 1 As shown, it includes: a thrust chamber and a needle-plug injector. The injector housing 2 of the needle-plug injector passes through the top of the thrust chamber 1 and is located inside the thrust chamber 1. The injector housing 2 has at least one main injection hole arranged radially. An annular gap is formed between the injector housing 2 and the top housing of the thrust chamber 1. The end of the injector housing 2 located in the thrust chamber 1 has a concave structure 22. A first cooling channel 21 is opened in the injector housing 2 above the main injection hole, in a direction opposite to the concave structure 22. The outlet of the first cooling channel 21 faces the interior of the housing of the thrust chamber 1. Below the main injection hole... The injector housing 2 has a second cooling channel 24 extending toward the injector housing 2, and the outlet of the second cooling channel 24 extends into the concave structure 22. The outlet of the second cooling channel 24 is connected to the swirl tangential hole 23 provided on the concave cavity wall of the concave structure 22. The injector housing 2 is used to inject liquid propellant in the propellant combination, and the annular gap between the top housing of the injector housing 2 and the thrust chamber 1 is used to inject another type of propellant in the propellant combination. It should be noted that the main injection hole is a multi-row hole provided on the outer periphery of the injector housing 2. In this embodiment, the main injection hole is a circular hole.

[0023] For example, in one specific embodiment, the propellant combination uses liquid oxygen and kerosene, liquid oxygen and liquid hydrogen, liquid oxygen and methane, or nitrogen tetroxide and unsymmetrical dimethylhydrazine; in this embodiment, the propellant combination uses liquid oxygen and kerosene, wherein the kerosene enters from port A. Figure 1 Inside the injector housing 2, liquid oxygen enters from port B into the annular gap formed between the injector housing 2 and the top housing of the thrust chamber 1.

[0024] For example, in one specific embodiment, the injector housing 2 located in the annular slot is radially provided with an annular boss; the annular boss has a first outlet channel with an outlet facing the interior of the thrust chamber 1, a first intermediate channel is formed inside the injector housing 2 between the main injection hole and the top of the annular boss, and a first inlet channel is formed on the inner wall of the injector housing 2 above the main injection hole. The first inlet channel communicates with the first outlet channel through the first intermediate channel to form a first cooling channel 21. In this embodiment, the first outlet channel is an annular channel. After the liquid propellant enters through the first inlet channel of the first cooling channel 21 and is discharged through the first outlet channel, a cooling oil film is formed between the liquid propellant and the outer wall of the injector housing 2.

[0025] For example, in one specific embodiment, the concave structure 22 includes a boss provided on the inner bottom end face of the injector housing 2, and a groove provided on the outer end face of the injector housing 2, wherein the groove is opened on the end face of the boss facing the thrust chamber 1, and the swirl tangential hole 23 is provided on the groove surface.

[0026] For example, in one specific embodiment, a second inlet channel is formed on the inner wall of the injector housing 2 below the main injection hole, a second intermediate channel is formed in the injector housing 2 along the direction opposite to the main injection hole, a connecting hole is formed radially along the end face of the injector housing 2, and a boss channel is formed in the boss along the axial direction of the boss. The second inlet channel is connected in sequence to the second intermediate channel, the connecting hole, the boss channel, and the swirling tangential hole 23 provided on the inner wall of the groove surface. The boss channel is an annular channel.

[0027] The present invention provides a liquid fuel engine, including a regenerative cooling structure for the thrust chamber needle plug of a liquid fuel engine according to an embodiment of the present invention.

[0028] A spacecraft according to the present invention includes: a liquid fuel engine according to an embodiment of the present invention.

[0029] The following is in conjunction with the appendix Figure 1 The present invention will be described in conjunction with specific embodiments:

[0030] As attached Figure 1As shown, this embodiment uses an open-cycle liquid oxygen and kerosene propellant combination as an example. Kerosene enters from port A at the top of the injector housing 2 of the needle-plug injector and jets out from the radial main injection hole of the injector housing 2. Liquid oxygen exits from port B through the annular gap between the top housing of the thrust chamber 1 and the injector housing 2. At this point, the liquid oxygen collides and mixes with the kerosene ejected from the radial main injection hole and burns after ignition by the igniter, generating high-temperature combustion gas. This gas fills the entire space of the thrust chamber 1 in the form of the main combustion zone and various recirculation zones. Finally, the combustion gas leaves the engine after passing through the combustion chamber and nozzle, providing thrust to the engine. The injector housing 2 is cooled by kerosene. The specific cooling process is as follows: kerosene enters from port A at the top of the injector housing 2 of the needle-plug injector and is jetted out from the radial main injection hole of the injector housing 2. At the same time, the kerosene entering the injector housing 2 enters from the first cooling channel 21 and is sprayed out from the annular channel outlet of the first cooling channel 21. The kerosene sprayed out from the annular channel outlet forms a cooling oil film between the kerosene and the outer periphery of the injector housing 2, that is, the kerosene carries away the heat of the injector housing 2 from the first cooling channel 21, thereby achieving cooling. It enters from the second cooling channel 24 and enters the swirl tangential hole 23 from the outlet of the second cooling channel 24. Under the centrifugal action of the swirl tangential hole 23, a spray is formed, and the heat is carried away from the head of the injector housing 2 of the needle-plug injector. That is, the kerosene effectively protects the needle head by pushing open the main return zone of high-temperature gas and changing the mixing ratio of the near-wall zone, thereby achieving regenerative cooling of the injector housing 2.

[0031] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber, comprising: A thrust chamber and a needle-bolt injector, wherein the injector housing of the needle-bolt injector passes through the top of the thrust chamber and is provided in the thrust chamber, and the injector housing is provided with at least one main injection hole in the radial direction of the injector housing located in the thrust chamber, characterized in that an annular gap is formed between the injector housing and the top housing of the thrust chamber, and the injector housing is provided with a concave structure at the end of the thrust chamber; a first cooling channel is provided in the injector housing above the main injection hole along the direction opposite to the concave structure, and the outlet of the first cooling channel faces the interior of the housing of the thrust chamber; a second cooling channel is provided in the injector housing below the main injection hole along the direction towards the injector housing, and the outlet of the second cooling channel extends into the concave structure, and the outlet of the second cooling channel communicates with a swirling tangential hole provided on the concave wall of the concave structure; The injector housing is used to inject liquid propellant into the propellant combination, while the circumferential gap between the injector housing and the top housing of the thrust chamber is used to inject another type of propellant into the propellant combination.

2. The regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber according to claim 1, characterized in that, The propellant combination uses one of the following combinations: liquid oxygen and kerosene, hydrogen peroxide and hydrocarbons, nitrogen oxides and hydrocarbons, liquid oxygen and liquid hydrogen, or liquid oxygen and methane.

3. The regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber according to claim 1, characterized in that, The injector housing located in the annular gap has an annular boss radially arranged; the annular boss has a first outlet flow channel with the outlet facing the inside of the thrust chamber, a first intermediate flow channel is opened in the injector housing between the main injection hole and the top of the annular boss, and a first inlet flow channel is opened on the inner wall of the injector housing above the main injection hole. The first inlet flow channel is connected to the first outlet flow channel through the first intermediate flow channel to form a first cooling flow channel.

4. The regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber according to claim 3, characterized in that, After the liquid propellant enters through the first inlet channel of the first cooling channel and exits through the first outlet channel, a cooling oil film is formed between the liquid propellant and the outer wall of the injector housing.

5. The regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber according to claim 1, characterized in that, The concave structure includes a boss on the bottom inner end face of the injector housing and a groove on the outer end face of the injector housing. The groove is located on the end face of the boss facing the thrust chamber, and the swirl tangential hole is located on the surface of the groove.

6. The regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber according to claim 5, characterized in that, A second inlet channel is opened on the inner wall of the injector housing below the main injection hole. A second intermediate channel is opened in the injector housing in a direction opposite to the main injection hole. A connecting hole is opened radially along the end face of the injector housing. A boss channel is opened in the boss along the axial direction of the boss. The second inlet channel is connected in sequence to the second intermediate channel, the connecting hole, the boss channel, and the swirl tangential hole provided on the inner wall of the groove.

7. A liquid fuel engine, characterized in that, include: A regenerative cooling structure for the needle plug head of a liquid fuel engine thrust chamber, as described in any one of claims 1-6.

8. A spacecraft, characterized in that, include: A liquid fuel engine as described in any one of claims 7.

Images