Thrust chamber and expansion cycle engine

Abstract

The embodiment of the present application provides a kind of thrust chamber and expansion cycle engine.The thrust chamber includes: inner wall;Outer wall, which is coaxially arranged with the inner wall;Cooling flow channel, at least containing a continuous spiral flow channel, which is spirally arranged between the inner wall and the outer wall;Spiral flow channel includes at least first section and second section along the axial direction of the thrust chamber, the heat flux density of the corresponding thrust chamber of first section is higher than the heat flux density of the corresponding thrust chamber of second section, and the helix angle of first section is less than the helix angle of second section.Set different sections and apply different helix angles in different sections, which is conducive to improving the cooling matching relationship of different areas of the thrust chamber, reducing the risk of local overheating, and improving the heat absorption and vaporization capacity of the coolant, to support the engine to obtain higher turbine driving power.

Description

Technical Field

[0001] This application relates to the field of aerospace technology, and in particular to a thrust chamber and expansion cycle engine. Background Technology

[0002] Expander cycle engines are widely used in space launch vehicles due to their simple structure, high reliability, and high specific impulse. Their working principle involves using waste heat from the inner wall of the thrust chamber to heat and vaporize the fuel flowing through the cooling channels. The resulting high-temperature, high-pressure fuel vapor drives a turbopump. Therefore, the heat exchange efficiency of the thrust chamber's cooling channels directly determines the available work to drive the turbopump, and consequently, the combustion chamber pressure and thrust level achievable by the engine.

[0003] Existing thrust chamber cooling channels are often difficult to design specifically for the differences in heat flux density in different regions of the thrust chamber. If the coolant flow path within the cooling channel is short, the heat exchange time between the coolant and the high-temperature wall is limited, resulting in insufficient fuel heat absorption and vaporization. Conversely, simply extending the coolant flow path to enhance heat exchange may increase flow resistance. Furthermore, the cooling requirements of high heat flux density regions such as the thrust chamber body and expansion section differ from those of relatively low heat flux density regions such as the contraction section and nozzle. If existing cooling channels use uniform flow parameters, it can easily lead to a mismatch between cooling capacity and flow resistance in different regions. Therefore, existing thrust chambers still suffer from limited regenerative cooling heat exchange efficiency, insufficient cooling in localized high heat flux regions, and difficulty in coordinating coolant flow resistance. Summary of the Invention

[0004] This application addresses existing technical problems by proposing a thrust chamber and expansion cycle engine, aiming to improve the heat exchange efficiency of the cooling channel of the thrust chamber.

[0005] In a first aspect, embodiments of this application provide a thrust chamber, comprising: an inner wall; an outer wall coaxially disposed with respect to the inner wall; and a cooling channel, including at least one continuous spiral channel, the spiral channel being wound around the inner wall and the outer wall; the spiral channel including at least a first section and a second section along the axial direction of the thrust chamber, wherein the heat flux density of the thrust chamber corresponding to the first section is higher than the heat flux density of the thrust chamber corresponding to the second section, and the helix angle of the first section is smaller than the helix angle of the second section.

[0006] In some embodiments, the first section corresponds to the thrust chamber body and / or expansion section of the thrust chamber.

[0007] In some embodiments, the cooling channel further includes a variable cross-section section, the hydraulic diameter of which gradually increases along the extension direction of the variable cross-section section.

[0008] In some embodiments, the helix angle of the second section gradually increases along the extension direction of the cooling channel.

[0009] In some embodiments, the second section corresponds to the contraction section of the thrust chamber and / or the nozzle.

[0010] In some embodiments, the cross-sectional shape of the cooling channel includes at least one of a rectangle, a trapezoid, or a semicircle.

[0011] In some embodiments, a spiral guide rib or a spiral groove is provided on the outer surface of the inner wall, and the spiral guide rib or the spiral groove, together with the inner wall and the outer wall, forms the spiral flow channel.

[0012] In some embodiments, a spiral guide rib or a spiral groove is provided on the inner surface of the outer wall, and the spiral guide rib or the spiral groove, together with the inner wall and the outer wall, forms the spiral flow channel.

[0013] In some embodiments, the cooling channel further includes a liquid collection ring, and multiple independent spiral channels are distributed along the axial direction of the thrust chamber. At least two spiral channels are connected through the liquid collection ring to form cascaded or parallel channels.

[0014] Secondly, embodiments of this application provide an expansion cycle engine, comprising: a fuel pump, a turbine, a gas generator, and the aforementioned thrust chamber. The inlet of a cooling channel of the thrust chamber is connected to the outlet of the fuel pump, and the outlet of the cooling channel is connected to the gas generator or the combustion chamber that drives the turbine.

[0015] The beneficial technical effects of the technical solutions provided in this application include: In this application, the cooling channel includes at least one continuous spiral channel, in which the coolant flows spirally along the thrust chamber axis within the thrust chamber. The actual flow path of the coolant from the inlet to the outlet is increased relative to the corresponding axial length, and the contact path and duration between the coolant and the high-temperature thrust chamber wall are also correspondingly extended. Therefore, this facilitates more thorough heat exchange between the coolant and the thrust chamber wall during the flow process.

[0016] The helical flow channel includes a first section and a second section along the thrust chamber axis. The heat flux density of the thrust chamber corresponding to the first section is higher than that corresponding to the second section, and the helix angle of the first section is smaller than that of the second section. Based on this configuration, in the first section with relatively high heat flux density, the smaller helix angle allows the coolant to form more helical circulation paths per unit axial length, thus relatively increasing the heat transfer process within this section. Conversely, in the second section with relatively low heat flux density, the larger helix angle allows the coolant to meet the heat transfer requirements of subsequent regions without continuously maintaining a high helical circulation intensity. The helix angle of the cooling channel can be differentiated according to the heat flux distribution in different regions, which is beneficial for matching the cooling requirements and flow resistance between different regions of the thrust chamber and also for the subsequent system's utilization of coolant thermal energy.

[0017] Additional aspects and advantages of this application will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of this application. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 A schematic diagram of the overall segmented structure of the thrust chamber provided in an embodiment of this application; Figure 2 A schematic diagram of the radial cross-sectional structure of the inner wall, outer wall, and cooling channel of the thrust chamber body in the embodiment of this application; Figure 3 A schematic diagram of the structure in which the spiral flow channel in the thrust chamber is arranged along the axial direction of the thrust chamber, as provided in the embodiments of this application; Figure 4 This is a schematic diagram of a rectangular cross-section cooling channel provided in an embodiment of this application. Figure 5 This is a schematic diagram of a cooling channel with a trapezoidal cross-section provided in an embodiment of this application. Figure 6 This is a schematic diagram of a cooling channel whose cross-sectional dimensions vary along the extension direction, as provided in an embodiment of this application.

[0019] Explanation of reference numerals in the attached figures: 200 - Thrust chamber; 210 - Combustion chamber; 201 - Thrust chamber body; 202 - Contraction section; 203 - Expansion section; 204 - Nozzle; 1-Inner wall; 2-outer wall; 3-Cooling channel; 31-Helical channel; 311-First section; 312-Second section; 32-Helical groove. Detailed Implementation

[0020] The embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the embodiments described below with reference to the accompanying drawings are exemplary descriptions for explaining the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions of the embodiments of this application.

[0021] Those skilled in the art will understand that, unless specifically stated otherwise, the terms "described" and "the" as used herein may also include plural forms. It should be further understood that the term "comprising" as used in the specification of this application means the presence of the described features, integers, and / or components, but does not exclude implementations of other features, information, data components, and / or combinations thereof supported by the art. The term "and / or" as used herein refers to at least one of the items defined by the term; for example, "A and / or B" can be implemented as "A," or as "B," or as "A and B."

[0022] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0023] The thrust chamber and expansion cycle engine provided in this application are intended to solve the technical problems in the prior art.

[0024] The technical solution of this application and how it solves the above-mentioned technical problems are described in detail below with specific embodiments. It should be noted that the following embodiments can be referenced, learned from, or combined with each other, and the same terms, similar features, and similar implementation steps in different embodiments will not be described again.

[0025] like Figures 1 to 6 As shown, this application embodiment provides a thrust chamber 200, including: an inner wall 1, an outer wall 2, and a cooling channel 3. The outer wall 2 is coaxially arranged with the inner wall 1. The cooling channel 3 includes at least one continuous spiral channel 31, which is wound between the inner wall 1 and the outer wall 2. The spiral channel 31 includes at least a first section 311 and a second section 312 along the axial direction of the thrust chamber 200. The heat flux density of the thrust chamber 200 corresponding to the first section 311 is higher than that of the thrust chamber 200 corresponding to the second section 312, and the helix angle of the first section 311 is smaller than that of the second section 312.

[0026] The process of fuel flowing within the cooling channels constitutes the regenerative cooling process of the thrust chamber 200. Before entering the combustion chamber to participate in combustion, the fuel first flows through the cooling channels located between the inner wall 1 and the outer wall of the thrust chamber 200. During this flow, it exchanges heat with the high-temperature walls of the thrust chamber 200, thereby carrying away the heat from the walls and achieving cooling protection for the thrust chamber 200. At the same time, the fuel itself absorbs heat and heats up during this process. Therefore, this process achieves both cooling of the thrust chamber 200 and preheating of the fuel and energy recovery, hence the name regenerative cooling. The fuel within the cooling channels can also be referred to as a coolant or regenerative coolant.

[0027] The cooling channel in the thrust chamber 200 includes at least one continuous spiral channel 31, which allows the coolant to flow in a spiral manner along the axial direction of the thrust chamber 200. This increases the effective flow length of the coolant in the thrust chamber 200 and prolongs the heat exchange time between the coolant and the high-temperature wall, thereby improving the heat exchange efficiency of the coolant regeneration cooling.

[0028] Furthermore, since the heat flux density of the thrust chamber 200 corresponding to the first section 311 is higher than that of the thrust chamber 200 corresponding to the second section 312, and the helix angle of the first section 311 is smaller than that of the second section 312, the number of coolant helical turns and heat exchange path can be increased in the first section 311 with higher heat flux density, which is beneficial to improving the cooling capacity within the first section 311. Further, a larger helix angle is designed in the second section 312 with lower heat flux density, which can reduce the flow resistance of the coolant in the cooling channel while meeting heat exchange requirements. Setting different sections and applying different helix angles in different sections can improve the cooling matching relationship of different areas of the thrust chamber 200, which is beneficial to reducing the risk of local overheating and improving the heat absorption and vaporization capacity of the coolant, thus supporting the engine to obtain higher turbine drive power.

[0029] In some embodiments, such as Figure 1 and Figure 3 As shown, the first section 311 corresponds to the thrust chamber body 201 and / or expansion section 203 of the thrust chamber 200.

[0030] Since the thrust chamber body and expansion section are areas with high heat flux density in the thrust chamber 200, placing the first section 311 with a smaller helix angle in these areas can increase the number of helical turns and effective flow length of the coolant in these areas, prolong the heat exchange time between the coolant and the high-temperature wall, thereby enhancing the local cooling capacity of the thrust chamber body and expansion section, reducing the risk of local overheating and ablation, and improving the thermal stability of the thrust chamber 200 and its ability to withstand higher combustion chamber pressures.

[0031] In some embodiments, such as Figure 6As shown, the cooling channel 3 also includes a variable cross-section section, the hydraulic diameter of which gradually increases along the extension direction of the variable cross-section section. The hydraulic diameter is four times the ratio of the cross-sectional area to the perimeter.

[0032] As the coolant continuously absorbs heat and may vaporize during its flow through the 200 cooling channel of the thrust chamber, its volume gradually expands. By gradually increasing the hydraulic diameter of the variable cross-section section along the extension direction, the cooling channel can adapt to the volume change of the coolant after heating. This helps to mitigate the increase in flow resistance and pressure drop caused by the rapid increase in flow velocity, and helps to maintain stable coolant flow. This, in turn, helps to improve the stability of the regeneration cooling process and provides support for the coolant to further absorb heat and perform subsequent work.

[0033] In some embodiments, the helix angle of the second section 312 gradually increases along the extension direction of the cooling channel 3. The helix angle of the second section 312 ranges from 20° to 40°. For example, when the coolant enters the second section 312 of the cooling channel 3, the helix angle is 25°, and when the coolant leaves the second section 312 of the cooling channel 3, the helix angle is 35°.

[0034] The heat flux density in the thrust chamber region corresponding to the second section 312 is relatively low. By gradually increasing the helix angle of the second section 312 along the extension direction, it is beneficial to meet the heat exchange requirements of the subsequent region while gradually reducing the number of helical turns per unit axial length. This helps to reduce the increasing trend of flow resistance, maintain the stability of the coolant flow along the flow path, and make the cooling channel parameters more matched with the heat flux distribution of the thrust chamber 200, thereby improving the overall efficiency of the regenerative cooling process.

[0035] In some embodiments, such as Figure 1 and Figure 3 As shown, the second section 312 corresponds to the contraction section 202 of the thrust chamber 200 and / or the nozzle 204.

[0036] Since the heat flux density of the contraction section 202 and the nozzle 204 is relatively low compared to that of the thrust chamber body 201 and the expansion section 203, setting the second section 312 in the above-mentioned area allows the region to adopt a relatively large or gradually increasing helical angle along the flow path. This helps to reduce the increasing trend of flow resistance while meeting cooling requirements, improves the flow adaptability and cooling distribution of the nozzle rear section, reduces the risk of local overheating, and improves the overall efficiency of the thrust chamber regenerative cooling process.

[0037] In some embodiments, such as Figures 4 to 6 As shown, the cross-sectional shape of the cooling channel 3 includes at least one of the following: rectangular, trapezoidal, or semi-circular.

[0038] Setting the cross-sectional shape of the cooling channel to any of the rectangular, trapezoidal, or semi-circular shapes can provide a variety of cross-sectional configuration options for the cooling channel. This is beneficial for adapting the design of the cooling channel according to the heat exchange requirements, flow requirements, and structural implementation methods at different locations. It also facilitates the synergistic optimization of heat exchange performance and flow performance, and improves the engineering adaptability of the solution.

[0039] In some embodiments, such as Figures 4 to 6 As shown, a spiral guide rib or spiral groove 32 is provided on the outer surface of the inner wall 1. The spiral guide rib or spiral groove 32, together with the inner wall 1 and the outer wall 2, form a spiral flow channel 31.

[0040] The outer surface of the inner wall 1 is provided with a spiral guide rib or spiral groove 32. The spiral guide rib or spiral groove 32, together with the inner wall 1 and the outer wall, form a spiral flow channel 31, which is conducive to guiding and limiting the flow of coolant along a predetermined spiral path. The coolant passes through the spiral heat exchange path stably, which is conducive to improving the stability and reliability of the regeneration cooling process.

[0041] In some embodiments, such as Figures 4 to 6 As shown, a spiral guide rib or spiral groove is provided on the inner surface of the outer wall 2, and the spiral guide rib or spiral groove together with the inner wall 1 and the outer wall 2 to form a spiral flow channel 31.

[0042] The inner surface of the outer wall is provided with a spiral guide rib or spiral groove 32. The spiral guide rib or spiral groove 32, together with the inner wall 1 and the outer wall, form a spiral flow channel 31. Compared with the embodiment in which the spiral guide rib or spiral groove 32 is provided on the outer surface of the inner wall 1, this embodiment provides the guide structure forming the spiral flow channel 31 on the inner surface of the outer wall. While guiding and limiting the spiral flow path of the coolant, it provides another structural option for the construction of the spiral flow channel 31, which is conducive to improving the layout flexibility and engineering adaptability of the thrust chamber 200 cooling flow channel design.

[0043] In some embodiments, the cooling channel 3 includes a liquid collecting ring and multiple independent spiral channels 31 distributed along the axial direction of the thrust chamber 200. At least two spiral channels 31 are connected through the liquid collecting ring to form cascaded or parallel channels.

[0044] By dividing the cooling channel into multiple independent spiral channels 31 and using a liquid collection ring to achieve cascading or parallel connection between the multiple channels, it is beneficial to achieve zoned coolant flow control, improve the cooling matching relationship between different areas of the thrust chamber 200, and increase the flexibility of cooling channel design.

[0045] Based on the same inventive concept, this application provides an expansion cycle engine, which includes a fuel pump, a turbine, a gas generator, and the aforementioned thrust chamber 200. The inlet of the cooling channel 3 of the thrust chamber 200 is connected to the outlet of the fuel pump, and the outlet of the cooling channel 3 is connected to the gas generator or combustion chamber 210 that drives the turbine.

[0046] It should be noted that since the expansion cycle engine provided in this application embodiment includes the thrust chamber provided in this application embodiment, the expansion cycle engine provided in this application embodiment also has the above-mentioned beneficial effects of the thrust chamber provided in this application embodiment, which will not be repeated here.

[0047] The following is combined with Figures 1 to 6 The structure of the thrust chamber and the expansion cycle engine of some embodiments of this application will be described in more detail.

[0048] like Figures 1 to 3 As shown, this application embodiment provides a thrust chamber 200, which includes an inner wall 1, an outer wall 2, and a cooling channel 3 disposed between the inner wall 1 and the outer wall 2. The inner wall 1 is located radially inside the thrust chamber 200, and the outer wall 2 is sleeved on the radially outside of the inner wall 1, and the outer wall 2 is coaxially disposed with the inner wall 1. The inner side of the inner wall 1 forms a combustion chamber 210 and an internal channel of the nozzle communicating with the combustion chamber 210. The cooling channel 3 is formed between the outer surface of the inner wall 1 and the inner surface of the outer wall 2, for supplying fuel to flow before entering the combustion chamber 210.

[0049] In the illustrated embodiment, the thrust chamber 200 has a thrust chamber body 201, a contraction section 202, an expansion section 203, and a nozzle 204 along the fuel or gas flow direction. The thrust chamber body 201 corresponds to the region where the combustion chamber 210 is located; the contraction section 202 is located between the thrust chamber body 201 and the expansion section 203; the expansion section 203 is located between the contraction and expansion regions of the nozzle; and the nozzle 204 is located on the side of the expansion section 203 away from the combustion chamber 210. These sections are used to identify different axial regions of the thrust chamber 200. In other embodiments, the specific length and boundary position of each section can be determined according to the actual configuration of the thrust chamber 200.

[0050] In this embodiment, the cooling channel 3 includes at least one continuous spiral channel 31. The spiral channel 31 is disposed between the inner wall 1 and the outer wall 2, and extends spirally along the outer periphery of the inner wall 1. Specifically, the spiral channel 31 extends around the axial direction of the inner wall 1, so that after the fuel enters from the inlet of the cooling channel 3, it can move along the axial direction of the thrust chamber 200 and around the circumference of the inner wall 1 in a spiral trajectory until it flows out from the outlet of the cooling channel 3.

[0051] like Figure 2 as well as Figures 4 to 6As shown, in one specific embodiment, a spiral groove 32 is provided on the outer surface of the inner wall 1. The spiral groove 32 extends spirally along the outer surface of the inner wall 1 and is located between the inner wall 1 and the outer wall 2. The groove wall of the spiral groove 32 and the inner surface of the outer wall 2 together define a spiral flow channel 31 for fuel flow. More specifically, the spiral groove 32 constitutes a channel space for fuel flow, the radially inner side of which is defined by the inner wall 1, the radially outer side by the outer wall 2, and the circumferential sides by adjacent spiral segments of the spiral groove 32, thereby forming a spiral flow channel 31 that extends continuously along the outer circumference of the inner wall 1.

[0052] In another alternative forming method, a spiral guide rib can be provided on the inner surface of the outer wall 2, and the spiral guide rib on the inner surface of the outer wall 2, the inner wall 1, and the outer wall 2 together form a spiral flow channel 31. That is, the spiral flow channel 31 can be formed by a guide structure on the outer surface side of the inner wall 1 or by a guide structure on the inner surface side of the outer wall 2.

[0053] The helical flow channel 31, along the axial direction of the thrust chamber 200, includes a first section 311 and a second section 312. The heat flux density of the thrust chamber 200 region corresponding to the first section 311 is higher than that of the thrust chamber 200 region corresponding to the second section 312, and the helix angle of the first section 311 is smaller than that of the second section 312. In a specific example, the first section 311 corresponds to the expansion section 203 of the thrust chamber 200, and the second section 312 corresponds to the nozzle 204 of the thrust chamber 200. In this case, the helical flow channel 31 located at the expansion section 203 has a smaller helix angle, while the helical flow channel 31 located at the nozzle 204 has a larger helix angle.

[0054] In other examples, the first segment 311 may correspond to at least one of the thrust chamber body 201 and the expansion section 203, and the second segment 312 may correspond to at least one of the contraction section 202 and the nozzle 204. This correspondence is used to illustrate the configuration relationship between different segments of the helical flow channel 31 and different axial regions of the thrust chamber 200, and does not require that the first segment 311 must simultaneously cover both the thrust chamber body 201 and the expansion section 203, nor does it require that the second segment 312 simultaneously cover both the contraction section 202 and the nozzle 204.

[0055] In this embodiment, the helix angle of the first section 311 can be 20°. The helix angle of the second section 312 can gradually increase along the extension direction of the cooling channel 3. For example, along the flow direction of fuel in the second section 312, the helix angle of the second section 312 can gradually increase from 25° to 35°. In this case, the fuel enters the second section 312 at a smaller helix angle, then gradually transitions to a larger helix angle along the extension direction of the second section 312, and continues to flow along the helix channel 31 towards the outlet of the cooling channel 3.

[0056] like Figures 4 to 6 As shown, the cross-sectional shape of the cooling channel 3 can be determined based on the fit between the inner wall 1, the outer wall 2, and the spiral groove 32. The spiral groove 32 in different figures can have different cross-sectional shapes or different trends in cross-sectional size variation.

[0057] In a specific example, such as Figure 4 As shown, the cross-sectional shape of the cooling channel 3 is rectangular. Specifically, the spiral groove 32 has a rectangular groove structure in the cross-section perpendicular to the extension direction of the spiral channel 31. The radial inner side of the spiral groove 32 is defined by the inner wall 1, the radial outer side is defined by the outer wall 2, and the circumferential sides are defined by the groove wall, thereby forming a flow area with a rectangular cross-section.

[0058] In another specific example, such as Figure 5 As shown, the cross-sectional shape of the cooling channel 3 is trapezoidal. Specifically, the spiral groove 32 has a trapezoidal groove structure in the cross-section perpendicular to the extension direction of the spiral channel 31. The opening side of the trapezoidal groove structure is set towards the outer wall 2 or the inner wall 1. The spiral groove 32, the inner wall 1, and the outer wall 2 together enclose a flow area with a trapezoidal cross-section.

[0059] In yet another specific example, such as Figure 6 As shown, the cross-sectional shape of the cooling channel 3 is rectangular, and the cross-sectional area of ​​the cooling channel 3 gradually increases along the extension direction of the cooling channel 3. Specifically, Figure 6 The spiral groove 32 in the middle has a rectangular groove structure in the cross section perpendicular to the extension direction of the spiral flow channel 31, along... Figure 6 As shown, from top to bottom, the density of each rectangular groove structure gradually decreases, and the cross-sectional area of ​​a single rectangular groove structure gradually increases, so that the cooling channel 3 formed by the spiral groove 32, the inner wall 1 and the outer wall 2 together constitutes a variable cross-section section.

[0060] Rectangular, trapezoidal, or semi-circular cross-sections can all be continuously arranged along the extension direction of the helical flow channel 31. Figures 4 to 6 Although the cross-sectional shapes of the spiral grooves 32 differ in the different embodiments shown, they are all located between the inner wall 1 and the outer wall 2, and together with the inner wall 1 and the outer wall 2, define the spiral flow channel 31 for fuel flow. In this embodiment, the cooling flow channel 3 may also include a variable cross-section section. The variable cross-section section is located within at least a portion of the length of the cooling flow channel 3, and the hydraulic diameter of the cross-section of the variable cross-section section gradually increases along the extension direction of the variable cross-section section. Specifically, the hydraulic diameter is four times the ratio of the area of ​​the cross-section to the perimeter of the cross-section. Along the flow direction of the fuel in the variable cross-section section, the flow cross-section of the variable cross-section section gradually changes, so that the fuel flows from one end of the variable cross-section section to the other end through a gradually changing flow channel cross-section. The variable cross-section section may be located in the spiral flow channel 31, or it may be located in other flow channel sections of the cooling flow channel 3 that are connected to the spiral flow channel 31.

[0061] In a further flow channel organization, the cooling channel 3 also includes a liquid collecting ring. The cooling channel 3 may include multiple independent spiral channels 31 distributed along the axial direction of the thrust chamber 200, with at least two spiral channels 31 connected by the liquid collecting ring. When forming a cascaded flow channel, fuel first enters an upstream spiral channel 31, flows along that channel 31, enters the liquid collecting ring, and then enters another downstream spiral channel 31, continuing to flow along the downstream spiral channel 31. When forming a parallel flow channel, the liquid collecting ring is connected to at least two spiral channels 31 respectively. After entering the liquid collecting ring, fuel can enter its corresponding spiral channel 31, or multiple spiral channels 31 can converge into the liquid collecting ring before flowing to the outlet of the cooling channel 3.

[0062] This application embodiment also provides an expansion cycle engine. The expansion cycle engine includes a fuel pump, a turbine, a gas generator, and the aforementioned thrust chamber 200. The inlet of the cooling channel 3 of the thrust chamber 200 is connected to the outlet of the fuel pump, and the outlet of the cooling channel 3 is connected to the gas generator driving the turbine or to the combustion chamber 210. The fuel pump delivers fuel to the cooling channel 3 of the thrust chamber 200. After flowing through the cooling channel 3, the fuel flows out from the outlet of the cooling channel 3 and enters the gas generator or the combustion chamber 210.

[0063] When the expansion cycle engine is operating, the fuel pump delivers fuel to the inlet of the cooling channel 3. After entering the cooling channel 3, the fuel first flows along the spiral channel 31 formed between the inner wall 1 and the outer wall 2. Confined by the spiral groove 32, the fuel circulates around the outer periphery of the inner wall 1 and moves axially towards the outlet of the cooling channel 3 along the thrust chamber 200. When the fuel flows through the first section 311, it flows along the spiral path of the first section 311; when the fuel continues to flow into the second section 312, it flows along the spiral path of the second section 312 and continues to flow downstream according to the changing spiral angle of the second section 312. If the cooling channel 3 has a variable cross-section section, the fuel continues to advance along the gradually changing channel cross-section when passing through the variable cross-section section. If the cooling channel 3 has multiple independent spiral channels 31 and liquid collecting rings, the fuel flows between adjacent spiral channels 31, switching, collecting, or distributing through the liquid collecting rings. After the fuel flows out of the outlet of the cooling channel 3, it enters the gas generator to drive the turbine, or enters the combustion chamber 210 to participate in combustion.

[0064] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0065] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0066] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0067] The above description is only a partial embodiment of this application. It should be noted that for those skilled in the art, other similar implementation methods based on the technical concept of this application, without departing from the technical concept of this application, also fall within the protection scope of the embodiments of this application.

Claims

1. A thrust chamber for a pulse detonation engine, characterized by, include: Inner wall; The outer wall is coaxially arranged with the inner wall; The cooling channel includes at least one continuous spiral channel, which is wound around the inner wall and the outer wall; The spiral flow channel includes at least a first section and a second section along the thrust chamber axis. The heat flux density of the thrust chamber corresponding to the first section is higher than that of the thrust chamber corresponding to the second section, and the helix angle of the first section is smaller than that of the second section.

2. The thrust chamber of a expansion cycle engine of claim 1, wherein, The first section corresponds to the thrust chamber body and / or expansion section of the thrust chamber.

3. The thrust chamber of the expander cycle engine according to claim 1, characterized in that, The cooling channel also includes a variable cross-section section, the hydraulic diameter of which gradually increases along the extension direction of the variable cross-section section.

4. The thrust chamber of the expander cycle engine according to claim 1, characterized in that, The helix angle of the second section gradually increases along the extension direction of the cooling channel.

5. The thrust chamber of the expander cycle engine according to claim 4, characterized in that, The second section corresponds to the contraction section of the thrust chamber and / or the nozzle.

6. The thrust chamber of the expander cycle engine according to any one of claims 1 to 5, characterized in that, The cross-sectional shape of the cooling channel includes at least one of the following: rectangular, trapezoidal, or semi-circular.

7. The thrust chamber of the expander cycle engine according to any one of claims 1 to 5, characterized in that, The outer surface of the inner wall is provided with a spiral guide rib or spiral groove, and the spiral guide rib or spiral groove, the inner wall and the outer wall together form the spiral flow channel.

8. The thrust chamber of the expander cycle engine according to any one of claims 1 to 5, characterized in that, The inner surface of the outer wall is provided with a spiral guide rib or a spiral groove, which together with the inner wall and the outer wall form the spiral flow channel.

9. The thrust chamber of the expander cycle engine according to any one of claims 1 to 5, characterized in that, The cooling channel also includes a liquid collection ring, and multiple independent spiral channels are distributed along the axial direction of the thrust chamber. At least two spiral channels are connected through the liquid collection ring to form cascaded or parallel channels.

10. An expansion cycle engine, characterized in that, It includes a fuel pump, a turbine, a gas generator, and a thrust chamber as described in any one of claims 1 to 9, wherein the inlet of a cooling channel of the thrust chamber is connected to the outlet of the fuel pump, and the outlet of the cooling channel is connected to the gas generator or the combustion chamber that drives the turbine.

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