Combustion chamber semi-regenerative cooling structure, gas generator, engine and liquid rocket

Abstract

The embodiment of the present application provides a combustion chamber semi-regenerative cooling structure, a gas generator, an engine and a liquid rocket, the combustion chamber semi-regenerative cooling structure comprises a throttle hole and a cooling channel arranged on the front section of the combustion chamber; the throttle hole is arranged on the outer wall of the front section of the combustion chamber, and the cooling channel is arranged between the inner wall and the outer wall of the front section of the combustion chamber; the throttle hole is in communication with the cooling channel and is used for guiding a small part of low-temperature fuel in a liquid collecting ring into the cooling channel; the cooling channel extends from one end of the front section of the combustion chamber provided with an injector to the other end, is used for guiding the low-temperature fuel out of the front section of the combustion chamber, and is used for spraying the low-temperature fuel on the inner wall of the rear section of the combustion chamber connected with the front section of the combustion chamber, so that the inner wall of the front section of the combustion chamber and the inner wall of the rear section of the combustion chamber connected with the front section of the combustion chamber are cooled. The combustion chamber semi-regenerative cooling structure, the gas generator, the rocket engine and the liquid rocket provided by the present application can effectively improve the manufacturing process and the problem of complex structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of liquid rocket, in particular to a combustion chamber semi-regenerative cooling structure, a gas generator, an engine and a liquid rocket. BACKGROUND

[0002] The gas generator of liquid rocket engine is one of the core components of the engine, which functions to generate high-temperature and high-pressure gas to drive the turbine to work and then enter the thrust chamber for combustion or discharge. Due to the limitation of turbine material, the gas generator is designed to burn off the stoichiometric ratio, and the temperature is generally 500-1000℃. If the local heat protection measures are not in place or local high temperature occurs, the gas generator wall surface is easy to be burned through. Taking liquid oxygen and kerosene propellant as an example, in order to ensure that the wall surface of the gas generator is not ablated during work, the injector is usually designed for zoned combustion or the regenerative cooling technology is used to cool the wall surface of the gas generator.

[0003] When the injector is designed for zoned combustion, a separate kerosene (fuel) nozzle is arranged in the edge zone to keep the wall surface in a lower mixture ratio condition and the combustion temperature is lower, while the liquid oxygen and kerosene dual-propellant nozzle is arranged in the center zone, the mixture ratio of the center zone is higher, and the combustion temperature is also higher.

[0004] When the regenerative cooling technology is used to cool the wall surface, the propellant needs to flow through the gap (commonly known as cooling jacket) between the inner wall and the outer wall of the nozzle first to achieve the purpose of cooling by absorbing heat, and then return to the injector and be injected into the combustion chamber for combustion.

[0005] In the process of implementing the present application, the inventors found that at least the following problems exist in the prior art:

[0006] For the gas generator, the temperature uniformity of the transverse cross-section gas is crucial. When the injector is designed for zoned combustion, a spoiler needs to be arranged downstream to enhance the gas mixing, the design and production of the gas generator are more complex, the injector needs to adopt different nozzle structures, the edge zone uses a separate fuel nozzle, and the center zone uses a dual-propellant nozzle. In addition, the spoiler and the downstream mixing space are needed, and the downstream gas mixing is easy to be uneven.

[0007] If the regenerative cooling method is used to protect the wall surface, since the cooling jacket needs to be arranged between the inner wall and the outer wall of the nozzle, the combustion chamber needs to be made into a double-wall structure, the cooling channel is made in the interlayer of the double-wall, and the propellant needs to flow back to the injector after cooling the wall surface. The whole manufacturing process of the flow channel is complex, which is not conducive to the structure layout, and the double-wall structure increases the overall weight of the rocket and causes the production cost to be too high. SUMMARY

[0008] In view of the above, the present application aims to provide a combustion chamber semi-regenerative cooling structure, a gas generator, a rocket engine and a liquid rocket to improve the manufacturing process and structural complexity in the prior art.

[0009] In a first aspect, the present application provides a combustion chamber semi-regenerative cooling structure, comprising a throttle hole and a cooling channel arranged on a front section of a combustion chamber; the throttle hole is arranged on an outer wall of the front section of the combustion chamber, and the cooling channel is arranged between an inner wall and the outer wall of the front section of the combustion chamber; the throttle hole is in communication with the cooling channel, and is used to guide a small amount of low-temperature fuel in a liquid collection ring into the cooling channel; the cooling channel extends from one end of the front section of the combustion chamber provided with an injector to the other end, and is used to guide the low-temperature fuel out of the front section of the combustion chamber and spray it on an inner wall of a rear section of the combustion chamber connected to the front section of the combustion chamber, so as to cool the inner wall of the front section of the combustion chamber and the inner wall of the rear section of the combustion chamber connected to the front section of the combustion chamber.

[0010] Further, a plurality of throttle holes are arranged along the circumference of the front section of the combustion chamber.

[0011] Further, the cooling channel comprises a first liquid collection cavity and a first channel; the throttle hole is in communication with the first liquid collection cavity; and the first liquid collection cavity is arranged along the circumference of the front section of the combustion chamber.

[0012] Further, the cooling channel further comprises a second liquid collection cavity and a second channel; the second liquid collection cavity is arranged along the circumference of the front section of the combustion chamber, and the second liquid collection cavity is connected to the outlet of the first channel.

[0013] Further, the number of the second channels is less than the number of the first channels, and the flow area of each of the second channels is not greater than the flow area of each of the first channels.

[0014] Further, the first channel and / or the second channel extends in a helical shape along the axial direction of the front section of the combustion chamber.

[0015] Further, the helix angle of the first channel and / or the second channel ranges from 10° to 40°.

[0016] In a second aspect, the present application provides a gas generator, comprising a front section of a combustion chamber and a rear section of a combustion chamber connected and arranged, the front section of the combustion chamber is provided with the combustion chamber semi-regenerative cooling structure as described above, the rear section of the combustion chamber is a single-layer wall structure, and the cooling channel is used to spray low-temperature fuel on the inner wall of the rear section of the combustion chamber at the outlet.

[0017] Further, the diameter of the inner wall of the rear section of the combustion chamber is not greater than the diameter of the inner wall of the front section of the combustion chamber at the outlet of the cooling channel.

[0018] Further, the gas generator further comprises a liquid collecting ring and an injector, the liquid collecting ring is arranged around the outer wall of the front section of the combustion chamber at an end away from the rear section of the combustion chamber, and forms a distribution channel of the low-temperature fuel between the outer wall of the front section of the combustion chamber; the injector is arranged on the inner wall of the front section of the combustion chamber at an end away from the rear section of the combustion chamber, the front section of the combustion chamber is provided with a flow guide hole, and the flow guide hole is respectively arranged in communication with the distribution channel and the injector.

[0019] Further, the throttle hole is arranged close to the flow guide hole, and the throttle hole and the injector are configured to: by controlling the size of the throttle hole and the size of the injection hole of the nozzle of the injector, 90%-97% of the low-temperature fuel in the liquid collecting ring enters the injector, and the remaining low-temperature fuel enters the cooling channel.

[0020] Further, the front section of the combustion chamber and the injector are integrally formed by additive manufacturing.

[0021] In a third aspect, an embodiment of the present application provides a rocket engine comprising the gas generator as described above.

[0022] In a fourth aspect, an embodiment of the present application provides a liquid rocket comprising the rocket engine as described above.

[0023] The above technical solutions have the following beneficial effects: the combustion chamber semi-regenerative cooling structure provided by the present application does not direct all the low-temperature fuel in the liquid collecting ring into the cooling channel as in the traditional process, but only a small part of the low-temperature fuel is directed into the cooling channel, and most of the low-temperature fuel still directly flows into the injector. The small part of the low-temperature fuel in the cooling channel does not participate in combustion, and the other part of the fuel enters the injector and is injected into the combustion chamber to participate in combustion. The low-temperature fuel in the cooling channel is used for cooling and regeneration. The low-temperature fuel entering the cooling channel is used to cool the inner wall of the front section of the combustion chamber and the rear section of the combustion chamber connected with the front section of the combustion chamber. The small part of the low-temperature fuel does not need to return to the injector, but directly enters the rear section of the combustion chamber. Therefore, the cooling channel has a simpler structure than the traditional cooling channel, and the manufacturing process is relatively simple. The gas generator provided by the present application sprays low-temperature fuel from the outlet of the cooling channel to the inner wall of the rear section of the combustion chamber to cool it. The rear section of the combustion chamber can adopt a single-layer wall structure, which simplifies the structure of the rear section of the combustion chamber, reduces the overall weight of the gas generator, and saves production costs. The rocket engine and the liquid rocket provided by the present application comprise the above-mentioned gas generator, and therefore also have the above-mentioned beneficial effects. BRIEF DESCRIPTION OF DRAWINGS

[0024] 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.

[0025] Figure 1 This is a partial cross-sectional view of the front section of the combustion chamber in an embodiment of the present invention (i.e., a structural schematic diagram of the semi-regenerative cooling structure of the combustion chamber).

[0026] Figure 2 yes Figure 1 A schematic diagram of the cross-sectional structure at the first channel of the semi-regenerative cooling structure of the combustion chamber.

[0027] Figure 3 This is a cross-sectional structural schematic diagram of a gas generator according to an embodiment of the present invention.

[0028] Figure 4 yes Figure 3 An enlarged schematic diagram of the structure at point A.

[0029] Figure 5 yes Figure 3 Enlarged schematic diagram of the structure at point B.

[0030] (Note: Figure 4 and Figure 5 The arrow in the image points to the direction of cryogenic fuel flow.

[0031] Figure 6 This is a schematic diagram of the cross-sectional structure of some components of the gas generator according to an embodiment of the present invention.

[0032] The meanings of the labels in the attached diagram are as follows:

[0033] 1. Front section of combustion chamber; 11. Throttling orifice; 12. Cooling channel; 121. First liquid collection chamber; 122. First channel; 123. Second liquid collection chamber; 124. Second channel; 13. Guide hole; 14. First flange; 15. Second flange; 2. Rear section of combustion chamber; 3. Liquid collection ring; 31. Distribution channel; 4. Injector. Detailed Implementation

[0034] Features and exemplary embodiments of various aspects of the present application will be described below in detail. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one of ordinary skill in the art that the present application can be practiced without some or all of these specific details. The description of the embodiments is merely intended to provide a more detailed understanding of the present application. In the drawings and the following description, well-known structures and techniques have not been shown in order to avoid obscuring the present application; and, for clarity, the size of some structures can be exaggerated. In addition, features described below can be combined in any suitable manner in one or more embodiments.

[0035] As shown in FIG. 1, the combustion chamber semi-regenerative cooling structure of the present embodiment includes a throttle hole 11 and a cooling channel 12 provided on the front section 1 of the combustion chamber; the throttle hole 11 is provided on the outer wall of the front section 1 of the combustion chamber, and the cooling channel 12 is provided between the inner wall and the outer wall of the front section 1 of the combustion chamber; the throttle hole 11 is in communication with the cooling channel 12, and is used to guide a small amount of low-temperature fuel in the liquid collection ring 3 into the cooling channel 12; the cooling channel 12 extends from one end of the front section 1 of the combustion chamber, where the injector 4 is provided, to the other end, and is used to guide the low-temperature fuel out of the front section 1 of the combustion chamber and spray it on the inner wall of the rear section 2 of the combustion chamber connected to the front section 1 of the combustion chamber, so as to cool the inner wall of the front section 1 of the combustion chamber and the inner wall of the rear section 2 of the combustion chamber connected to the front section 1 of the combustion chamber. Figure 1 Figure 2 The throttle hole 11 is used to throttle the low-temperature fuel, which increases the flow resistance and, together with the increase in the flow area of the channel, reduces the pressure drop and the flow rate. The throttle hole 11 is in communication with the cavity of the liquid collection ring 3, and only the low-temperature fuel entering the cooling channel 12 through the throttle hole 11 plays a role in cooling and regeneration, while most of the fuel directly enters the combustion chamber through the injector 4 to be burned. The low-temperature fuel in the cooling channel 12 absorbs the heat of the inner wall of the front section 1 of the combustion chamber after being cooled, and is sprayed on the inner wall of the rear section 2 of the combustion chamber at the outlet of the cooling channel 12, so as to cool the rear section 2 of the combustion chamber and participate in combustion at this location without entering the injector 4. Since the low-temperature fuel does not participate in combustion in the cooling channel 12, a smaller amount of fuel can be introduced to cool the downstream wall surface.

[0036] The throttle hole 11 is used to throttle the low-temperature fuel, which increases the flow resistance and, together with the increase in the flow area of the channel, reduces the pressure drop and the flow rate. The throttle hole 11 is in communication with the cavity of the liquid collection ring 3, and only the low-temperature fuel entering the cooling channel 12 through the throttle hole 11 plays a role in cooling and regeneration, while most of the fuel directly enters the combustion chamber through the injector 4 to be burned. The low-temperature fuel in the cooling channel 12 absorbs the heat of the inner wall of the front section 1 of the combustion chamber after being cooled, and is sprayed on the inner wall of the rear section 2 of the combustion chamber at the outlet of the cooling channel 12, so as to cool the rear section 2 of the combustion chamber and participate in combustion at this location without entering the injector 4. Since the low-temperature fuel does not participate in combustion in the cooling channel 12, a smaller amount of fuel can be introduced to cool the downstream wall surface.

[0037] ​A plurality of throttling holes 11 are evenly distributed on the circumferential outer wall of the fuel chamber head, and the throttling holes 11 are the main components for throttling the low-temperature fuel as the front channel for contacting the low-temperature fuel (cooling liquid), and the throttling pressure drop accounts for about 90% of the flow resistance of the semi-regenerative cooling structure of the entire combustion chamber. The low-temperature fuel after passing through the throttling holes 11 flows in the cooling channel 12, takes away the heat of the inner wall of the front section 1 of the combustion chamber, and enters the downstream combustion chamber rear section 2. The evenly distributed throttling holes 11 make the low-temperature fuel evenly distributed in the cooling channel 12 to ensure the uniformity of the temperature in the cooling channel 12 and avoid local overheating.

[0038] In some embodiments, the cooling channel 12 includes a first collecting cavity 121 and a first channel 122; the throttling holes 11 are arranged on the outer wall of the combustion chamber front section 1 corresponding to the first collecting cavity 121; the first collecting cavity 121 is arranged circumferentially around the combustion chamber front section 1; and a plurality of first channels 122 are evenly distributed along the circumference of the combustion chamber front section 1.

[0039] Specifically, the first collecting cavity 121 is arranged corresponding to the throttling holes 11, that is, each throttling hole 11 is arranged in communication with the first collecting cavity 121. The first collecting cavity 121 is arranged as a ring cavity circumferentially around the combustion chamber front section 1, and the low-temperature fuel can directly enter the first collecting cavity 121 through the throttling holes 11. The range of the distribution of the throttling holes 11 along the circumferential direction of the combustion chamber front section 1 coincides with the circumferential range of the ring cavity (for example, in some embodiments, the ring cavity is a whole circle ring arranged along the circumference). By evenly or non-uniformly distributing the plurality of throttling holes 11 along the circumference of the ring cavity according to the heat load, the low-temperature fuel is injected into the annular first collecting cavity 121 at multiple points, the fuel is collected and redistributed in the first collecting cavity 121, and the functions of uniform flow and uniform temperature are realized, thereby achieving the cooling of the combustion chamber front section 1.

[0040] In order to make the cooling effect of the cooling channel 12 better, in some embodiments, a second collecting cavity 123 and a second channel 124 can also be arranged. The second collecting cavity 123 is arranged circumferentially around the combustion chamber front section 1, and the second collecting cavity 123 is connected with the outlet of the first channel 122; a plurality of second channels 124 are evenly distributed along the circumference of the combustion chamber front section 1, the number of the second channels 124 is less than the number of the first channels 122, and the flow area of a single second channel 124 is not greater than the flow area of a single first channel 122. For example, the cross section of the second channel 124 can be smaller than the cross section of the first channel 122, and the number of the first channels 122 and the second channels 124 can be designed in multiples, for example, in some embodiments, the number of the first channels 122 is 1.5 to 2 times the number of the second channels 124.

[0041] The second collecting cavity 123 is in communication with the outlet of the first channel 122, and the low-temperature fuel enters the second collecting cavity 123 from the first channel 122, is collected and redistributed again, is further uniformly flowed and uniformly tempered, so as to realize good protection of the downstream fuel chamber assembly.

[0042] When the second channel 124 is not arranged and only the first channel 122 is arranged, the first channel 122 simultaneously plays the roles of conducting and throttling, so as to realize the protection of the downstream assembly. When the first channel 122 and the second channel 124 are arranged simultaneously, the first channel 122 only has the function of conducting, and the second channel 124 has the function of throttling, and the flow resistance of the second channel 124 accounts for about 10% of the flow resistance of the entire cooling structure. The cross sections of the first cooling channels 12 and the second cooling channels 12 are all rectangular, preferably, the cross sections of all the first cooling channels 12 are the same, the cross sections of all the second cooling channels 12 are the same, the total number of the second channels 124 is less than the total number of the first channels 122, the cross-sectional area of a single second channel 124 is not greater than the cross-sectional area of a single first channel 122, and preferably, the cross-sectional area of the second channel 124 is less than the cross-sectional area of the first channel 122, so as to better realize the throttling function.

[0043] The two collecting cavities are arranged along the circumferential direction of the combustor front section 1, and the two channels (the first channel 122 and the second channel 124) are arranged along the longitudinal direction of the combustor front section 1. For example, the extension trajectories of the two channels are straight lines, the plurality of first channels 122 are arranged in parallel along the axial direction of the combustor front section 1, and the plurality of second channels 124 are also arranged in parallel along the axial direction of the combustor front section 1. In order to make the cooling effect of the cooling channel 12 stronger, the first channel 122 and / or the second channel 124 can also extend in a spiral shape along the axial direction of the combustor front section 1, and the spiral angle is controlled in the range of 10° to 40°. The spiral-shaped cooling channel 12 prolongs the flow path of the low-temperature fuel between the inner and outer walls of the combustor front section 1, increases the contact time of the low-temperature fuel with the inner wall surface, and thus improves the cooling efficiency and effect of the cooling structure on the combustor front section 1. This design enables the cooling liquid to more fully absorb the heat of the inner wall, effectively reducing the temperature of the inner wall surface of the combustor front section 1. The spiral-shaped cooling channel 12 also helps the cooling liquid to be uniformly distributed between the inner and outer walls of the combustor front section 1, avoids the occurrence of local overheating of the wall surface, and improves the cooling effect. Since the spiral cooling channel 12 can make the heat distribution more uniform, the phenomenon of thermal stress concentration caused by too large local temperature difference can be reduced. The control of the spiral angle can facilitate the realization of additive manufacturing (3D printing).

[0044] For example, Figures 3 to 6As shown, the embodiment of the present application also provides a gas generator, which comprises a combustion chamber front section 1 and a combustion chamber rear section 2 connected together, the combustion chamber front section 1 is provided with the combustion chamber semi-regenerative cooling structure of the above embodiment, and the combustion chamber rear section 2 is a single-layer wall cylindrical structure, and the cooling channel 12 is used to spray the low-temperature fuel to the inner wall of the combustion chamber rear section 2 at the outlet.

[0045] Specifically, the combustion chamber front section 1 and the combustion chamber rear section 2 can be made of stainless steel or high-temperature alloy steel such as GH4169. If the combustion chamber front section 1 and the combustion chamber rear section 2 are made of the same or similar materials, they can be integrally formed. If the materials of the combustion chamber front section 1 and the combustion chamber rear section 2 are too different, they can be fixedly connected by welding. The combustion chamber rear section 2 is fixedly connected with the combustion chamber front section 1 at one end of the outlet of the cooling channel 12.

[0046] The diameter of the inner wall of the combustion chamber rear section 2 is not greater than the diameter of the inner wall of the combustion chamber front section 1 at the outlet of the cooling channel 12, so as to cool the inner wall of the combustion chamber rear section 2. Preferably, the diameter of the inner wall of the combustion chamber rear section 2 is the same as the diameter of the inner wall of the combustion chamber front section 1 at the connection (the outlet of the cooling channel 12), so that the low-temperature fuel can be sprayed along the inner wall of the combustion chamber rear section 2 after flowing out of the outlet of the second channel 124, and the second channel 124 uniformly distributed along the circumference of the combustion chamber front section 1 can uniformly spray the low-temperature fuel to the inner wall of the combustion chamber rear section 2, so that the cooling of the combustion chamber rear section 2 is more uniform and reliable. The low-temperature fuel in the cooling channel 12 does not participate in combustion in the cooling channel 12, but only takes away a little heat from the inner wall of the combustion chamber front section 1, and can only contact the flame in the central combustion zone after being sprayed from the outlet of the second channel 124 to the inner wall of the combustion chamber rear section 2, and then slowly start to burn, so that only a small amount of low-temperature fuel is needed to protect the inner wall of the combustion chamber rear section 2, thereby making the combustion chamber rear section 2 adopt a simple single-layer wall structure. The combustion chamber in the prior art is mostly a double-layer wall structure, and the design of the cooling channel 12 makes the overall structure of the combustion chamber complex, the manufacturing is complex, and the overall structure is heavy; and some combustion chambers with a single-layer wall structure need to separately provide cooling nozzles (i.e. a single set of fuel nozzles) in the edge area of the injector 4 to cool and lower the temperature of the inner wall. The low-temperature fuel of this structure is sprayed near the combustion chamber front section 1 and directly participates in combustion in the combustion chamber, and the cooling distance is short, which cannot effectively protect the combustion chamber rear section 2 downstream. The cooling structure of the present application delays the low-temperature fuel in the cooling channel 12 to the front end of the combustion chamber rear section 2, and a section of cooling liquid in the combustion chamber front section 1 is not burned, thereby prolonging the cooling distance of the cooling liquid, so that the wall of the downstream combustion chamber rear section 2 can be well protected at the outlet of the second channel 124, and the cooling liquid is used very little, and the cooling effect is very good.

[0047] The gas generator of the embodiment further comprises a liquid collecting ring 3 and an injector 4. The liquid collecting ring 3 is arranged on the circumferential outer wall of the front section 1 away from the rear section 2 of the combustion chamber and forms a distribution passage 31 for the low-temperature fuel between the outer wall of the front section 1 and the liquid collecting ring 3. The injector 4 is arranged on the inner wall of the front section 1 away from the rear section 2 of the combustion chamber. The front section 1 is provided with flow guide holes 13 which are uniformly distributed along the circumference of the front section 1. The flow guide holes 13 are respectively arranged in communication with the distribution passage 31 and the injector 4.

[0048] A first flange 14 is arranged on the circumferential outer wall of the front section 1 away from the rear section 2 of the combustion chamber. A second flange 15 is further arranged on the circumferential outer wall of the front section 1. The second flange 15 is arranged in spaced relation to the first flange 14. The two edges of the shell of the liquid collecting ring 3 are respectively fixedly connected to the first flange 14 and the second flange 15, thereby forming the distribution passage 31 between the liquid collecting ring 3 and the outer wall of the front section 1. In some embodiments, the liquid collecting ring 3 and the front section 1 of the combustion chamber can be integrally formed. The flow guide holes 13 and the throttle holes 11 are arranged on the outer wall of the front section 1 between the first flange 14 and the second flange 15. The flow guide holes 13 are arranged close to the first flange 14. In order to facilitate the formation of the flow guide holes 13 in the additive manufacturing process, the flow guide holes 13 can be designed as waist-shaped holes. The length direction of the waist-shaped holes is the same as the length direction of the front section 1 of the combustion chamber. The outer wall of the front section 1 close to the second flange 15 has a larger diameter than the outer wall close to the first flange 14.

[0049] The injector 4 is arranged in the inner cavity of the front section 1 of the combustion chamber and located within the range between the first flange 14 and the second flange 15. The injector 4 is integrally formed with the front section 1 of the combustion chamber through additive manufacturing. The low-temperature fuel in the liquid collecting ring 3 is injected into the inner cavity of the front section 1 of the combustion chamber through the flow guide holes 13 and ignited for combustion. Since the inner wall of the front section 1 of the combustion chamber can be cooled by the low-temperature fuel in the cooling passage 12, the injector 4 only needs to be provided with a double-element centrifugal nozzle, without the need to further provide a spoiler. The temperature uniformity of the horizontal cross-section of the gas is ensured, and the structure of the gas generator is simplified, thereby reducing the production cost.

[0050] The throttle hole 11 is arranged close to the flow guide hole 13 to facilitate the distribution of the low-temperature fuel. The throttle hole 11 and the injector 4 are configured to make 90%-97% of the low-temperature fuel in the liquid collecting ring 3 flow into the injector 4 and the rest of the low-temperature fuel flow into the cooling channel 12 by controlling the size of the throttle hole 11 and the size of the injection hole of the nozzle of the injector 4. The most of the fuel is guided into the injector 4 and only a small part of the low-temperature fuel is used as the cooling liquid to cool the inner wall of the combustion chamber, which not only ensures the efficiency of the fuel combustion but also simplifies the structure of the cooling channel 12. The low-temperature fuel used as the cooling liquid does not need to return to the injector 4 but directly enters the combustion chamber rear section 2 and participates in the combustion in the inner cavity of the combustion chamber rear section 2. The number of the flow guide holes 13 and the throttle holes 11 can be in a multiple relationship so that the flow guide holes 13 and the throttle holes 11 can be staggered, for example, the number of the flow guide holes 13 is three times the number of the throttle holes 11, and one throttle hole 11 is arranged every three flow guide holes 13. The flow guide holes 13 are mainly used to guide the flow to the injector 4, and the throttle holes 11 are used for throttling, and the aperture of the throttle hole 11 is smaller than that of the flow guide hole 13.

[0051] The liquid collecting ring 3, the injector 4 and the combustion chamber front section 1 can be integrally formed by additive manufacturing, which can reduce the workload of machining and welding and reduce the total number of parts and improve the reliability of the gas generator. Alternatively, the liquid collecting ring 3, the injector 4, the combustion chamber rear section 2 and the combustion chamber front section 1 can be manufactured respectively and then fixedly connected by welding, for example, the combustion chamber rear section 2 and the combustion chamber front section 1 can be fixedly connected by electron beam welding or laser welding, the liquid collecting ring 3 and the combustion chamber front section 1 can be fixedly connected by argon arc welding, and the inner wall of the combustion chamber front section 1 and the injector 4 can be fixedly connected by brazing.

[0052] The embodiment of the present application also provides a rocket engine comprising the gas generator.

[0053] The embodiment of the present application also provides a liquid rocket comprising the rocket engine.

[0054] The combustion chamber semi-regenerative cooling structure, the gas generator, the rocket engine and the liquid rocket provided by the embodiment of the present application adopt an integrated semi-regenerative cooling structure based on 3D printing, which adopts a two-stage throttling structure, a two-circle liquid collecting structure and a spiral channel structure, greatly improving the uniformity of the cooling liquid. The fuel in the injector is introduced into the middle or downstream of the combustion chamber through the cooling channel on the inner wall of the combustion chamber, so that the cooling liquid is extended and moved downward, and the downstream combustion chamber wall can be effectively protected by introducing less low-temperature fuel. The gas generator of the present application cancels the partitioned combustion design of the injector and the device of the spoiler, and adopts a double-element nozzle with the same injector arrangement structure, which simplifies the overall structure design of the device and greatly improves the uniformity of the gas temperature of the transverse section at the outlet end of the gas generator. The downstream combustion chamber (the rear section of the combustion chamber) of the gas generator of the embodiment of the present application is simple in structure and has a single wall, effectively reducing the overall weight of the gas generator. The combustion chamber semi-regenerative cooling structure, the gas generator, the rocket engine and the liquid rocket provided by the embodiment of the present application are simple and compact in structure, reduce the manufacturing process of multiple parts, reduce the cost, improve the reliability, meet the demand for efficient, reliable and stable combustion of liquid oxygen kerosene rocket engines using open cycle or closed cycle, and can be widely used in other types of liquid propellants.

[0055] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "up, down, inner and outer" is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first, second or third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0056] Unless otherwise explicitly specified and limited in the present application, the terms "mounting, connection, connection" should be understood broadly, for example: it can be fixed connection, detachable connection or integrated connection; it can also be mechanical connection, electrical connection or direct connection, it can also be indirectly connected through an intermediate medium, or it can be the communication between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0057] Although the present application has been described with reference to the preferred embodiments, various modifications can be made thereto and equivalents can be substituted for elements thereof without departing from the scope of the present application. In particular, the technical features mentioned in each embodiment can be combined in any way as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A semi-regenerative cooling structure for a combustion chamber, characterized in that, It includes a throttling orifice (11) and a cooling channel (12) on the front section (1) of the combustion chamber; the throttling orifice (11) is located on the outer wall of the front section (1) of the combustion chamber, and the cooling channel (12) is located between the inner wall and the outer wall of the front section (1) of the combustion chamber; the throttling orifice (11) and the cooling channel (12) are connected and configured to guide a small portion of the low-temperature fuel in the liquid collection ring (3) into the cooling channel (12); the cooling channel (12) extends from one end of the front section (1) of the combustion chamber equipped with an injector (4) to the other end, and is used to discharge the low-temperature fuel from the front section (1) of the combustion chamber and spray it onto the inner wall of the rear section (2) of the combustion chamber connected to the front section (1) of the combustion chamber, so as to cool the inner wall of the front section (1) of the combustion chamber and the inner wall of the rear section (2) of the combustion chamber connected to the front section (1); The cooling channel (12) includes a first liquid collection chamber (121), a first channel (122), a second liquid collection chamber (123), and a second channel (124) arranged sequentially along the longitudinal direction of the front section (1) of the combustion chamber; the first liquid collection chamber (121) is connected to the inlet of the first channel (122), and the second liquid collection chamber (123) is connected to the inlet of the second channel (124); the throttling orifice (11) is connected to the first liquid collection chamber (121); the first liquid collection chamber (121) surrounds the combustion chamber. The combustion chamber front section (1) is arranged circumferentially; the second liquid collection chamber (123) is arranged circumferentially around the combustion chamber front section (1), and the second liquid collection chamber (123) is connected to the outlet of the first channel (122); a plurality of second channels (124) are evenly distributed along the circumference of the combustion chamber front section (1); the number of second channels (124) is less than the number of first channels (122), and the flow area of ​​a single second channel (124) is not greater than the flow area of ​​a single first channel (122).

2. The combustion chamber semi-regenerative cooling structure as described in claim 1, characterized in that, A plurality of the throttling orifices (11) are arranged at circumferential intervals along the front section (1) of the combustion chamber.

3. The combustion chamber semi-regenerative cooling structure as described in claim 1, characterized in that, The first channel (122) and / or the second channel (124) extend in a spiral shape along the axial direction of the front section (1) of the combustion chamber.

4. The combustion chamber semi-regenerative cooling structure as described in claim 3, characterized in that, The helix angle of the first channel (122) and / or the second channel (124) ranges from 10° to 40°.

5. A gas generator, characterized in that, The combustion chamber includes a front section (1) and a rear section (2) connected together. The front section (1) is provided with a semi-regenerative cooling structure as described in any one of claims 1 to 4. The rear section (2) is a single-wall structure. The cooling channel (12) is used to inject cryogenic fuel onto the inner wall of the rear section (2) at the outlet.

6. The gas generator as described in claim 5, characterized in that, It also includes a liquid collecting ring (3) and an injector (4). The liquid collecting ring (3) surrounds the outer circumferential wall of the front section (1) of the combustion chamber away from the rear section (2) of the combustion chamber, and forms a low-temperature fuel distribution channel (31) between it and the outer wall of the front section (1) of the combustion chamber. The injector (4) is provided on the inner wall of the front section (1) of the combustion chamber away from the rear section (2) of the combustion chamber. The front section (1) of the combustion chamber is provided with a guide hole (13), which is connected to the distribution channel (31) and the injector (4) respectively.

7. The gas generator as described in claim 6, characterized in that, The throttling orifice (11) is located close to the guide hole (13). The throttling orifice (11) and the injector (4) are configured such that by controlling the size of the throttling orifice (11) and the size of the nozzle of the injector (4), 90%-97% of the cryogenic fuel in the liquid collecting ring (3) enters the injector (4), and the remaining cryogenic fuel enters the cooling channel (12).

8. The gas generator as described in claim 6, characterized in that, The combustion chamber front section (1) and the injector (4) are manufactured as a single piece using additive manufacturing technology.

9. A rocket engine, characterized in that, Includes the gas generator as described in any one of claims 5 to 8.

10. A liquid rocket, characterized in that, Including the rocket engine as described in claim 9.

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