Gas generator, rocket propulsion system and rocket

Abstract

This application provides a gas generator, a rocket propulsion system, and a rocket. The gas generator includes: a combustion chamber configured as an axially extending cylindrical structure, the combustion chamber having an upstream end and a downstream end; a needle-plug injector disposed at the upstream end of the combustion chamber, the needle-plug injector including a liquid oxygen injection channel and a first kerosene injection channel, the liquid oxygen injection channel extending axially along the combustion chamber to a liquid oxygen injection outlet, the first kerosene injection channel extending axially along the combustion chamber to a first kerosene injection outlet, the first kerosene injection outlet surrounding the liquid oxygen injection outlet, and both the liquid oxygen injection outlet and the first kerosene injection outlet communicating with the interior of the combustion chamber; and a secondary injector sleeved on the outside of the combustion chamber, the secondary injector having a second kerosene injection channel communicating with the interior of the combustion chamber. The centerline of the second kerosene injection channel is inclined downstream relative to the axis of the combustion chamber.

Description

Technical Field

[0001] This application relates to the field of aerospace technology, and in particular to a gas generator, rocket propulsion device and rocket. Background Technology

[0002] Liquid rocket engines typically require a turbopump to pressurize the propellant components to meet the combustion chamber pressure and propellant supply requirements. The gas generator is the gas-generating component in a liquid rocket engine. It generates high-temperature, high-pressure gas from the combustion of the propellant components within the combustion chamber, which drives the turbopump. For liquid oxygen-kerosene engines, the gas generator typically uses liquid oxygen as the oxidizer and kerosene as fuel. The liquid oxygen and kerosene are injected into the combustion chamber and mixed and burned.

[0003] Needle injectors are a commonly used type of injector. They are typically located at one end of the combustion chamber and introduce liquid oxygen and kerosene into the chamber through liquid oxygen and kerosene channels. Under low mixture ratio conditions, the kerosene flow rate in the gas generator is relatively large. When the kerosene mainly enters the combustion chamber near the needle injector, there are issues with insufficient kerosene evaporation and atomization, or difficulty in controlling the kerosene entry position and injection direction downstream of the needle injector. These problems affect the mixing and combustion process of liquid oxygen and kerosene within the combustion chamber and may lead to insufficient combustion efficiency in the gas generator. Summary of the Invention

[0004] This application addresses the existing technical problems by proposing a gas generator, comprising: The combustion chamber is configured as a cylindrical structure extending axially, the combustion chamber having an upstream end and a downstream end; A needle-plug injector is disposed at the upstream end of the combustion chamber. The needle-plug injector includes a liquid oxygen injection channel and a first kerosene injection channel. The liquid oxygen injection channel extends axially along the combustion chamber to a liquid oxygen injection outlet. The first kerosene injection channel extends axially along the combustion chamber to a first kerosene injection outlet. The first kerosene injection outlet is arranged around the liquid oxygen injection outlet, and both the liquid oxygen injection outlet and the first kerosene injection outlet are in communication with the interior of the combustion chamber. A secondary injector is fitted onto the outside of the combustion chamber. The secondary injector has a second kerosene injection channel, which communicates with the interior of the combustion chamber. Along the axial direction of the combustion chamber, the outlet of the second kerosene injection channel is located downstream of the first kerosene injection outlet, and the centerline of the second kerosene injection channel is inclined downstream relative to the axis of the combustion chamber.

[0005] In some embodiments, the inner peripheral wall of the secondary injector and the outer peripheral wall of the combustion chamber together define a kerosene chamber, the kerosene chamber being arranged around the combustion chamber circumferentially, and the second kerosene injection channel connecting the kerosene chamber with the interior of the combustion chamber.

[0006] In some embodiments, the secondary injector is provided with a kerosene chamber inlet communicating with the kerosene chamber, the kerosene chamber extending continuously along the circumference of the combustion chamber, and the kerosene chamber being configured to distribute kerosene entering the kerosene chamber through the kerosene chamber inlet to the second kerosene injection channel.

[0007] In some embodiments, the secondary injector has a plurality of second kerosene injection channels, which are located at the same axial position in the combustion chamber and are distributed circumferentially at intervals along the combustion chamber.

[0008] In some embodiments, the kerosene flow rate injected into the combustion chamber through the first kerosene injection channel is greater than the kerosene flow rate injected into the combustion chamber through the second kerosene injection channel.

[0009] In some embodiments, the kerosene flow rate injected into the combustion chamber through the second kerosene injection channel is 10% to 20% of the total kerosene flow rate injected into the combustion chamber through the first kerosene injection channel and the second kerosene injection channel.

[0010] In some embodiments, the upstream end of the combustion chamber includes an inner bottom facing the interior of the combustion chamber, and the needle injector includes a central rod passing through the inner bottom along the axial direction of the combustion chamber and a needle head disposed on the central rod near the downstream end; the liquid oxygen injection channel is formed in the central rod and extends to the needle head, the needle head having the liquid oxygen injection outlet, the liquid oxygen injection outlet being located upstream of the second kerosene injection channel along the axial direction of the combustion chamber.

[0011] In some embodiments, the needle tip has a plurality of liquid oxygen injection outlets arranged in a ring around the axis of the central rod. The liquid oxygen injection outlets are strip-shaped holes with rounded ends, and the length direction of the liquid oxygen injection outlets is parallel to the axis of the central rod.

[0012] In some embodiments, the distance between the outlet of the second kerosene injection channel and the inner bottom along the axial direction of the combustion chamber is 1 to 1.5 times the inner diameter of the combustion chamber.

[0013] In some embodiments, the first kerosene injection channel is defined by the outer wall of the central rod and the inner wall of the kerosene channel surrounding the central rod, and the outlet of the first kerosene injection channel is disposed around the needle head.

[0014] In some embodiments, the angle between the centerline of the second kerosene injection channel and the axis of the combustion chamber is 30° to 60°.

[0015] In some embodiments, under the rated operating conditions of the gas generator, the ratio of the liquid oxygen jet flow rate ejected from the liquid oxygen injection channel to the kerosene jet flow rate ejected from the first kerosene injection channel is 2 to 4.

[0016] This application also provides a rocket propulsion device, including a turbopump and a gas generator as described in any of the foregoing embodiments, wherein the exhaust port of the gas generator is connected to the intake port of the turbopump.

[0017] This application also provides a rocket, including a gas generator as described in any of the foregoing embodiments, or including a rocket propulsion device as described in the foregoing embodiments.

[0018] The first kerosene injection outlet is positioned around the liquid oxygen injection outlet, allowing liquid oxygen and the first kerosene to enter the combustion chamber separately. This improves the mixing efficiency of the liquid oxygen and the first kerosene, thus facilitating the formation of a high-temperature gas combustion zone downstream of the first kerosene injection outlet for secondary kerosene evaporation and atomization. The centerline of the second kerosene injection channel is inclined downstream relative to the axis of the combustion chamber, giving the secondary kerosene a downstream velocity component. This helps the secondary kerosene enter the high-temperature gas combustion zone downstream of the needle injector, further improving the degree of evaporation and atomization of the secondary kerosene and alleviating the problem of insufficient atomization caused by a large kerosene flow rate under low mixture ratio conditions. When the gas generator serves as the gas supply component upstream of the turbopump, the improved combustion efficiency in the combustion chamber helps increase the energy utilization rate of the gas entering the turbopump. Simultaneously, the secondary kerosene, injected laterally from the combustion chamber, may form a local low-temperature zone, which helps reduce the local heat load of the gas at the turbopump inlet. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments are briefly described below. It should be understood that the following drawings only show some embodiments of this application and do not constitute a limitation on the scope of protection of this application.

[0020] Figure 1 This is a schematic diagram of the structure of a gas generator provided in an embodiment of this application; Figure 2 for Figure 1 A partial structural diagram of the gas generator in section A of the middle circle; Figure 3 for Figure 1 A partial structural diagram of the gas generator in section B of the middle circle.

[0021] Explanation of reference numerals in the attached figures: 1-Combustion chamber; 11-Inner bottom; 2-Needle-plug injector; 21-Liquid oxygen injection channel; 211-Liquid oxygen injection outlet; 22-First kerosene injection channel; 221-First kerosene injection outlet; 23-Center rod; 24-Needle-plug head; 25-Inner wall of kerosene channel; 3-Secondary injector; 31-Kerosene chamber; 32-Secondary kerosene injection channel; 33-Kerosene chamber inlet. Detailed Implementation

[0022] 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.

[0023] 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."

[0024] 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.

[0025] Liquid rocket engines typically include components such as a thrust chamber, a gas generator, a turbopump, and propellant supply lines. The gas generator introduces propellants such as liquid oxygen or kerosene into the combustion chamber for combustion, generating fuel gas. This fuel gas then enters the turbopump to drive it and pressurize the propellant. The combustion chamber is usually an axially extending cylindrical structure. The propellant enters the combustion chamber from the upstream end and burns inside, forming fuel gas that flows axially downstream.

[0026] A needle-plug injector is a type of injector used to inject propellant into a combustion chamber. The needle-plug injector is typically located at one end of the combustion chamber and delivers liquid oxygen and kerosene through different injection channels. After entering the combustion chamber through the needle-plug injector, the liquid oxygen and kerosene come into contact, mix, and burn within the combustion chamber. In a liquid oxygen-kerosene gas generator, kerosene can enter the combustion chamber as fuel, and liquid oxygen can enter as an oxidizer. The two combust within the combustion chamber to form the gas used to drive the turbopump.

[0027] During the operation of the gas generator, the position, direction, and flow rate of kerosene entering the combustion chamber affect the contact process between kerosene and liquid oxygen, as well as the evaporation, atomization, and combustion processes of kerosene within the combustion chamber. For ease of explanation of the structural relationships in the embodiments below, the end in which the propellant enters the combustion chamber is referred to as the upstream end, the direction of gas flow out is referred to as the downstream direction; the direction along the extension direction of the combustion chamber is referred to as the axial direction, and the direction around the axis of the combustion chamber is referred to as the circumferential direction.

[0028] This application provides a gas generator, such as... Figures 1 to 3 As shown, the gas generator includes: Combustion chamber 1 is configured as a cylindrical structure extending axially, and combustion chamber 1 has an upstream end and a downstream end; A needle-plug injector 2 is disposed at the upstream end of the combustion chamber 1. The needle-plug injector 2 includes a liquid oxygen injection channel 21 and a first kerosene injection channel 22. The liquid oxygen injection channel 21 extends axially along the combustion chamber 1 to a liquid oxygen injection outlet 211, and the first kerosene injection channel 22 extends axially along the combustion chamber 1 to a first kerosene injection outlet 221. The first kerosene injection outlet 221 is arranged around the liquid oxygen injection outlet 211, and both the liquid oxygen injection outlet 211 and the first kerosene injection outlet 221 are in communication with the interior of the combustion chamber 1. The secondary injector 3 is sleeved on the outside of the combustion chamber 1. The secondary injector 3 has a second kerosene injection channel 32, which is connected to the inside of the combustion chamber 1. Along the axial direction of the combustion chamber 1, the outlet of the second kerosene injection channel 32 is located downstream of the first kerosene injection outlet 221, and the centerline of the second kerosene injection channel 32 is inclined downstream relative to the axis of the combustion chamber 1.

[0029] The first kerosene injection outlet 221 is arranged around the liquid oxygen injection outlet 211, so that liquid oxygen and the first kerosene enter the combustion chamber 1 respectively. This helps to improve the mixing efficiency of liquid oxygen and the first kerosene, and facilitates the formation of a high-temperature gas combustion zone for secondary kerosene evaporation and atomization downstream of the first kerosene injection outlet 221.

[0030] The centerline of the second kerosene injection channel 32 is inclined downstream relative to the axis of the combustion chamber 1, giving the secondary kerosene a downstream velocity component. This helps the secondary kerosene enter the high-temperature gas region downstream of the needle injector 2, which is beneficial for improving the evaporation and atomization of the secondary kerosene and can alleviate the problem of insufficient atomization caused by a large kerosene flow rate under low mixing ratio conditions.

[0031] When the gas generator serves as the gas supply component upstream of the turbopump, the improved combustion efficiency in combustion chamber 1 helps to increase the energy utilization rate of the gas entering the turbopump. At the same time, the secondary kerosene injected from the side of combustion chamber 1 may form a local low-temperature zone, which helps to reduce the local heat load of the gas at the turbopump inlet.

[0032] In some embodiments, such as Figure 1 and Figure 3 As shown, the inner peripheral wall of the secondary injector 3 and the outer peripheral wall of the combustion chamber 1 together define the kerosene chamber 31. The kerosene chamber 31 is arranged around the combustion chamber 1 in the circumferential direction. The second kerosene injection channel 32 connects the kerosene chamber 31 with the interior of the combustion chamber 1.

[0033] The kerosene chamber 31 is defined by the inner peripheral wall of the secondary injector 3 and the outer peripheral wall of the combustion chamber 1, and is arranged around the combustion chamber 1 circumferentially; the second kerosene injection channel 32 connects the kerosene chamber 31 and the interior of the combustion chamber 1. Thus, kerosene entering the kerosene chamber 31 can flow circumferentially along the combustion chamber 1 and enter the interior of the combustion chamber 1 through the second kerosene injection channel 32.

[0034] The kerosene chamber 31 is defined by the inner peripheral wall of the secondary injector 3 and the outer wall of the combustion chamber 1, so that the secondary kerosene flow path is arranged in the outer space of the combustion chamber 1. There is no need to process an independent annular flow channel inside the wall of the combustion chamber 1, which helps to simplify the processing and manufacturing of the combustion chamber 1. It can also avoid the formation of seams or uneven parts on the inner wall of the combustion chamber 1 due to the separate built-in flow channel structure, thereby reducing the risk of local ablation when the high-temperature gas flows through the inner wall of the combustion chamber 1.

[0035] In some embodiments, such as Figure 1 and Figure 3 As shown, the secondary injector 3 is provided with a kerosene chamber inlet 33 that communicates with the kerosene chamber 31. The kerosene chamber 31 extends continuously along the circumference of the combustion chamber 1. The kerosene chamber 31 is configured to distribute the kerosene that enters the kerosene chamber 31 through the kerosene chamber inlet 33 to the second kerosene injection channel 32.

[0036] Kerosene can enter the kerosene chamber 31 through the kerosene inlet 33, and flow circumferentially within the combustion chamber 1, before entering the second kerosene injection channel 32. Since the kerosene chamber 31 extends continuously circumferentially along the combustion chamber 1, it helps to distribute the kerosene entering the kerosene chamber 31 to the second kerosene injection channel 32, facilitating the injection of kerosene into the interior of the combustion chamber 1 through the second kerosene injection channel 32.

[0037] In some embodiments, such as Figure 1 and Figure 3 As shown, the secondary injector 3 has multiple second kerosene injection channels 32, which are located at the same axial position in the combustion chamber 1 and are distributed circumferentially along the combustion chamber 1.

[0038] Kerosene can enter the interior of combustion chamber 1 from different circumferential positions through multiple second kerosene injection channels 32. The multiple second kerosene injection channels 32 are located at the same axial position in combustion chamber 1, which helps ensure that the kerosene injected from the second kerosene injection channels 32 corresponds to the same axial region within combustion chamber 1. The multiple second kerosene injection channels 32 are distributed circumferentially and at intervals along combustion chamber 1, which helps reduce the possibility of kerosene entering the interior of combustion chamber 1 from only a single circumferential position, thus facilitating contact between the kerosene and the combustion gas within combustion chamber 1.

[0039] In some embodiments, the kerosene flow rate injected into the combustion chamber 1 through the first kerosene injection channel 22 is greater than the kerosene flow rate injected into the combustion chamber 1 through the second kerosene injection channel 32.

[0040] The kerosene injected into the combustion chamber 1 through the first kerosene injection channel 22 is the main feedstock, while the kerosene injected into the combustion chamber 1 through the second kerosene injection channel 32 is the surplus feedstock. A larger portion of the kerosene enters the combustion chamber 1 through the first kerosene injection channel 22, which helps the liquid oxygen ejected from the liquid oxygen injection outlet 211 to contact the kerosene ejected from the first kerosene injection outlet 221 near the needle injector 2; a smaller portion of the kerosene enters the downstream area of ​​the needle injector 2 through the second kerosene injection channel 32, which helps to utilize the existing high-temperature environment in the combustion chamber 1 to promote the evaporation and atomization of this portion of the kerosene.

[0041] In some embodiments, the kerosene flow rate injected into the combustion chamber 1 through the second kerosene injection channel 32 is 10% to 20% of the total kerosene flow rate injected into the combustion chamber 1 through the first kerosene injection channel 22 and the second kerosene injection channel 32, for example, 10%, 12%, 14%, 16%, 18% and 20%.

[0042] The kerosene flow rate injected into the combustion chamber 1 through the second kerosene injection channel 32 accounts for a predetermined proportion of the total kerosene flow rate. Limiting this proportion to 10% to 20% helps keep the amount of kerosene injected into the combustion chamber 1 within a controllable range. When the kerosene injected through the second kerosene injection channel 32 enters the downstream area of ​​the needle injector 2, it helps this portion of the kerosene evaporate and atomize in a high-temperature environment, and helps prevent excessive kerosene injection through the second kerosene injection channel 32 from affecting the contact process between liquid oxygen and the first kerosene near the needle injector 2.

[0043] In some embodiments, such as Figure 1 As shown, the upstream end of the combustion chamber 1 includes an inner bottom 11 facing the interior of the combustion chamber 1. The needle injector 2 includes a central rod 23 passing through the inner bottom 11 along the axial direction of the combustion chamber 1 and a needle head 24 disposed at one end of the central rod 23 extending into the combustion chamber 1. A liquid oxygen injection channel 21 is formed in the central rod 23 and extends to the needle head 24. The needle head 24 includes a liquid oxygen injection outlet 211 communicating with the liquid oxygen injection channel 21. The outlet of the liquid oxygen injection outlet 211 is located upstream of the second kerosene injection channel 32 along the axial direction of the combustion chamber 1.

[0044] Liquid oxygen can flow through the liquid oxygen injection channel 21 in the central rod 23 to the needle head 24, and enter the combustion chamber 1 through the liquid oxygen injection outlet 211; the outlet of the liquid oxygen injection outlet 211 is located upstream of the second kerosene injection channel 32, so that the liquid oxygen enters the upstream area before the kerosene injected into the second kerosene injection channel 32.

[0045] The outlet of the liquid oxygen injection outlet 211 and the outlet of the second kerosene injection channel 32 are axially sequentially positioned, which helps to form a contact area between liquid oxygen and first kerosene near the needle injector 2, and then allows the kerosene injected into the second kerosene injection channel 32 to enter the high-temperature environment downstream of this area, which is beneficial to the evaporation and atomization of the kerosene injected into the second kerosene injection channel 32.

[0046] In some embodiments, such as Figure 1 and Figure 2 As shown, the needle head 24 includes multiple liquid oxygen injection outlets 211, which are arranged in a ring around the axis of the central rod 23. The liquid oxygen injection outlets 211 are strip-shaped holes with rounded ends, and the length direction of the liquid oxygen injection outlets 211 is parallel to the axis of the central rod 23.

[0047] Multiple liquid oxygen injection outlets 211 allow liquid oxygen to enter the combustion chamber 1 from multiple circumferential positions of the needle head 24; the length direction of the liquid oxygen injection outlets 211 is parallel to the axis of the central rod 23, so that the liquid oxygen injection outlets 211 have an extension dimension in the axial direction of the central rod 23; the two ends of the liquid oxygen injection outlets 211 are rounded to help reduce the formation of sharp corners at the ends of the liquid oxygen injection outlets 211.

[0048] Multiple liquid oxygen injection outlets 211 are arranged in a ring around the axis of the central rod 23, which helps to improve the distribution of liquid oxygen in the circumferential direction of the needle head 24; the strip-shaped hole structure helps to expand the flow area of ​​a single liquid oxygen injection outlet 211; the rounded transition at both ends helps to reduce the local processing difficulty and the risk of sharp corner defects at the ends of the liquid oxygen injection outlets 211.

[0049] In some embodiments, the distance between the outlet of the second kerosene injection channel 32 and the inner bottom 11 along the axial direction of the combustion chamber 1 is 1 to 1.5 times the inner diameter of the combustion chamber 1.

[0050] The outlet of the second kerosene injection channel 32 maintains the aforementioned axial distance from the inner bottom 11, positioning the outlet of the second kerosene injection channel 32 at a predetermined position downstream of the liquid oxygen injection channel 21. After liquid oxygen is injected into the combustion chamber 1 through the liquid oxygen injection channel 21, an annular reflux zone and a high-temperature combustion gas zone are formed downstream of the liquid oxygen injection channel 21. Arranging the outlet of the second kerosene injection channel 32 at a distance from the inner bottom 11 that is 1 to 1.5 times the inner diameter of the combustion chamber 1 helps the secondary injected kerosene enter the edge of the annular reflux zone or the high-temperature combustion gas zone, and utilizes the high-temperature combustion gas in this zone to promote the evaporation and atomization of the secondary injected kerosene.

[0051] When the outlet of the second kerosene injection channel 32 is too close to the inner bottom 11, the secondary injected kerosene tends to enter the initial mixing zone near the liquid oxygen injection outlet 211 too early, affecting the formation of a stable initial combustion flow field between liquid oxygen and main kerosene near the liquid oxygen injection outlet 211. When the outlet of the second kerosene injection channel 32 is too far from the inner bottom 11, the secondary injected kerosene enters the combustion chamber 1 at a downstream position, reducing the available high-temperature backflow effect and shortening the evaporation, atomization, and mixing time of the secondary injected kerosene before entering the gas outlet. By limiting the axial distance between the outlet of the second kerosene injection channel 32 and the inner bottom 11 to 1 to 1.5 times the inner diameter of the combustion chamber 1, the stability of the initial combustion flow field near the needle injector 2 and the evaporation and atomization effect of the secondary injected kerosene can be balanced, thereby improving the combustion efficiency of the gas generator.

[0052] In some embodiments, such as Figure 1 As shown, the first kerosene injection channel 22 is defined by the outer wall of the central rod 23 and the inner wall 25 of the kerosene channel surrounding the central rod 23, and the outlet of the first kerosene injection channel 22 is arranged around the needle head 24.

[0053] Kerosene can flow along the space between the outer wall of the central rod 23 and the inner wall of the kerosene channel, and enter the combustion chamber 1 through the outlet of the first kerosene injection channel 22 provided around the needle head 24.

[0054] The outlet of the first kerosene injection channel 22 is arranged around the needle head 24, which helps the first kerosene to enter the combustion chamber 1 around the needle head 24, thereby increasing the chance of the first kerosene coming into contact with the liquid oxygen ejected from the liquid oxygen injection outlet 211 near the needle head 24.

[0055] In some embodiments, the angle between the centerline of the second kerosene injection channel 32 and the axis of the combustion chamber 1 is 30° to 60°, for example 30°, 40°, 50° and 60°.

[0056] The second kerosene injection channel 32 is connected to the interior of the combustion chamber 1 in a direction inclined relative to the axis of the combustion chamber 1, so that the kerosene injected from the second kerosene injection channel 32 has a tendency to move towards the interior of the combustion chamber 1 and downstream along the axis of the combustion chamber 1.

[0057] An angle of 30° to 60° helps the kerosene sprayed from the second kerosene injection channel 32 enter the downstream area of ​​the needle injector 2, and facilitates the contact of this part of the kerosene with the high-temperature gas. It also helps the kerosene sprayed from the second kerosene injection channel 32 enter the edge of the annular reflux zone or the high-temperature zone, which is beneficial to improving the evaporation and atomization effect of the kerosene sprayed from the second kerosene injection channel 32.

[0058] In some embodiments, under the rated operating conditions of the gas generator, the ratio of the liquid oxygen jet flow rate ejected from the liquid oxygen injection channel 21 to the kerosene jet flow rate ejected from the first kerosene injection channel 22 is 2 to 4.

[0059] The liquid oxygen ejected from the liquid oxygen injection channel 21 and the kerosene ejected from the first kerosene injection channel 22 have a predetermined jet momentum relationship near the needle-plug injector 2. Setting an appropriate jet momentum ratio helps to control the contact state between the liquid oxygen ejected from the liquid oxygen injection channel 21 and the kerosene ejected from the first kerosene injection channel 22 near the needle-plug injector 2. This helps to reduce the situation where the momentum of either the liquid oxygen or the first kerosene is too large, resulting in insufficient contact, and also helps to improve the mixing stability of the liquid oxygen and the first kerosene near the needle-plug injector 2.

[0060] This application also provides a rocket propulsion device, including a turbopump and a gas generator as described in any of the foregoing embodiments, wherein the exhaust port of the gas generator is connected to the intake port of the turbopump.

[0061] The gas generator injects kerosene into the combustion chamber 1 through the first kerosene injection channel 22 and the second kerosene injection channel 32, and injects liquid oxygen into the combustion chamber 1 through the liquid oxygen injection channel 21, which helps to improve the evaporation and atomization effect of the kerosene. After the gas enters the turbopump, it helps to improve the gas drive effect of the turbopump in the rocket propulsion system. When using a gas generator in a rocket propulsion system, it helps to reduce the risk of increased propellant consumption due to insufficient gas generator efficiency.

[0062] This application also provides a rocket, including a gas generator as described in any of the foregoing embodiments, or a rocket propulsion system as described in the foregoing embodiments.

[0063] The combustion chamber 1, needle-plug injector 2, secondary injector 3, first kerosene injection channel 22, second kerosene injection channel 32, and liquid oxygen injection channel 21 in the gas generator work together to improve kerosene evaporation and atomization, and thus enhance the efficiency of the gas generator. Using this gas generator in rockets helps improve the engine's specific impulse performance.

[0064] In some embodiments, the flow area of ​​the liquid oxygen injection outlet 211 can be determined based on the liquid oxygen propellant flow rate. Let the flow area of ​​a single liquid oxygen injection outlet 211 be... The number of liquid oxygen injection outlets 211 is n, and the density of liquid oxygen is... The flow coefficient of liquid oxygen injection outlet 211 is The liquid oxygen injection pressure drop is The flow rate of liquid oxygen propellant is The flow area of ​​a single liquid oxygen injection outlet 211 is... satisfy:

[0065] In the above formula, the total flow area of ​​the n liquid oxygen injection outlets 211 is n. Therefore, the flow rate of liquid oxygen propellant can be used as a basis. Liquid oxygen density Liquid oxygen injection pressure drop The flow area of ​​a single liquid oxygen injection outlet 211 is determined by the number n of liquid oxygen injection outlets 211. .

[0066] In some embodiments, the outer wall of the center rod 23 and the inner wall 25 of the kerosene channel together define a kerosene annular seam. Let the diameter of the needle head 24 be... The radial width of the kerosene annular joint is The number of liquid oxygen injection outlets 211 is The flow area of ​​a single liquid oxygen injection outlet 211 is The correction factor or flow coefficient is The radial width of the kerosene annular joint is... It can satisfy:

[0067] In the above formula, the kerosene annular gap is defined by the outer wall of the central rod 23 and the inner wall 25 of the kerosene channel surrounding the central rod 23. The first kerosene flows along the first kerosene injection channel 22 and enters the interior of the combustion chamber 1 through the kerosene annular gap.

[0068] In some embodiments, the liquid oxygen jet flow rate from the liquid oxygen injection outlet 211 and the kerosene jet flow rate from the first kerosene injection outlet 221 satisfy a predetermined momentum ratio. Let the liquid oxygen flow rate be... The liquid oxygen outlet velocity is The first kerosene flow rate is The first kerosene export speed is The momentum ratio is ,but:

[0069] In one specific implementation, The value is 2.

[0070] In some embodiments, the kerosene flow rate injected into the combustion chamber 1 through the second kerosene injection channel 32 is 10% to 20% of the total kerosene flow rate injected into the combustion chamber 1 through the first kerosene injection channel 22 and the second kerosene injection channel 32. In one specific embodiment, the kerosene flow rate injected into the combustion chamber 1 through the second kerosene injection channel 32 is 10% of the total kerosene flow rate.

[0071] Let the flow rate of kerosene injected into combustion chamber 1 through the second kerosene injection channel 32 be... The flow coefficient of the second kerosene injection channel 32 is The total flow area of ​​the multiple second kerosene injection channels 32 is The second kerosene injection pressure drop is The density of kerosene is ,but It can satisfy:

[0072] Therefore, the total flow area A2 of the multiple second kerosene injection channels 32 can be determined based on the kerosene flow rate of the second kerosene injection channels 32. Flow coefficient Second kerosene injection pressure drop and kerosene density Sure.

[0073] In some embodiments, the secondary injector 3 has A second kerosene injection channel 32, Each second kerosene injection channel 32 is a circular orifice of uniform diameter. Let the diameter of a single second kerosene injection channel 32 be... , The total flow area of ​​the second kerosene injection channel 32 is: ,but:

[0074] Accordingly, the orifice diameter of a single second kerosene injection channel 32 satisfy:

[0075] In some embodiments, the internal volume of combustion chamber 1 can be determined based on the throat area and characteristic length. The characteristic length, defined as the ratio of combustion chamber volume to nozzle throat area, is used to assess the average residence time of the propellant within the combustion chamber, ensuring complete combustion. Let the internal volume of combustion chamber 1 be... The area of ​​the throat is The feature length is ,but:

[0076] In some specific embodiments, the feature length The value is 3.

[0077] In some embodiments, the combustion chamber 1 includes a straight section. Let the inner diameter of the straight section of the combustion chamber 1 be... The gas flow density is The gas mass flow rate is Then the cross-sectional area of ​​the straight section of combustion chamber 1 is... It can satisfy:

[0078] Inner diameter of the straight section of combustion chamber 1 It can satisfy:

[0079] In some implementations, the shrinkage ratio is set to... The cross-sectional area of ​​the straight section of combustion chamber 1 is The area of ​​the throat is ,but:

[0080] Correspondingly, the inner diameter of the straight section of combustion chamber 1 It can satisfy:

[0081] In some embodiments, the volume of the kerosene chamber 31 can be determined based on the flow rate of kerosene injected into the combustion chamber 1 via the second kerosene injection channel 32. The kerosene chamber 31 extends continuously along the circumference of the combustion chamber 1, and the volume and flow cross-sectional area of ​​the kerosene chamber 31 can be configured to distribute the kerosene entering the kerosene chamber 31 via the kerosene chamber inlet 33 to multiple second kerosene injection channels 32.

[0082] Compared with the direct-flow and centrifugal gas generators in related technologies, the gas generator of this application has combustion stability and avoids local high-temperature erosion; the gas generator with secondary injection function in this application can improve combustion efficiency; and after being injected from the inner wall of the combustion chamber, it can reduce the temperature of the gas at the turbine inlet, which helps to protect the turbine from erosion.

[0083] 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.

[0084] In the description of this application, "upstream end" and "downstream end" can be understood according to the overall flow direction of propellant and combustion gases in the combustion chamber. (Refer to...) Figure 1 The upper end of combustion chamber 1 is the upstream end, and the lower end of combustion chamber 1 is the downstream end. Combustion chamber 1 is configured as a cylindrical structure extending axially. The upstream end of combustion chamber 1 is used to install needle injector 2, the middle part of combustion chamber 1 is supplied with liquid oxygen, kerosene and fuel gas, and the downstream end of combustion chamber 1 is used to discharge fuel gas.

[0085] like Figure 1 As shown in the illustration, this application provides a gas generator, including a combustion chamber 1, a needle injector 2, and a secondary injector 3. The needle injector 2 is located at the upstream end of the combustion chamber 1, with a portion of the needle injector 2 extending into the interior of the combustion chamber 1. The secondary injector 3 is sleeved on the outer side of the combustion chamber 1 and located in the outer region downstream of the needle injector 2. The needle injector 2 is used to introduce liquid oxygen and a first kerosene into the combustion chamber 1, and the secondary injector 3 is used to introduce a second kerosene into the combustion chamber 1. The first and second kerosene can come from the same kerosene supply source, or they can be supplied separately according to the actual pipeline layout.

[0086] Combustion chamber 1 has an upstream end and a downstream end. The upstream end of combustion chamber 1 includes an inner bottom 11 facing the interior of combustion chamber 1. The inner bottom 11 is located on the mounting side of needle-plug injector 2. A central rod 23 passes through the inner bottom 11 along the axial direction of combustion chamber 1 and extends into the interior of combustion chamber 1. The sidewalls of combustion chamber 1 are arranged around the axis of combustion chamber 1, and the secondary injector 3 is sleeved on the outside of the outer sidewalls of combustion chamber 1.

[0087] like Figure 1 and Figure 2 As shown, the needle-plug injector 2 includes a liquid oxygen injection channel 21 and a first kerosene injection channel 22. The liquid oxygen injection channel 21 extends axially along the combustion chamber 1 to the liquid oxygen injection outlet 211, and the first kerosene injection channel 22 extends axially along the combustion chamber 1 to the first kerosene injection outlet 221. Both the liquid oxygen injection outlet 211 and the first kerosene injection outlet 221 are in communication with the interior of the combustion chamber 1. The first kerosene injection outlet 221 is arranged around the liquid oxygen injection outlet 211, allowing liquid oxygen and first kerosene to enter the interior of the combustion chamber 1 through their respective outlets.

[0088] exist Figure 1 In the illustrated embodiment, the needle-plug injector 2 includes a central rod 23 and a needle-plug head 24. The central rod 23 passes through the inner bottom 11 along the axial direction of the combustion chamber 1, and the needle-plug head 24 is disposed at the end of the central rod 23 that extends into the combustion chamber 1. A liquid oxygen injection channel 21 is formed within the central rod 23 and extends to the needle-plug head 24. The needle-plug head 24 has a liquid oxygen injection outlet 211, which communicates with the liquid oxygen injection channel 21. Liquid oxygen flows through the liquid oxygen injection channel 21 to the needle-plug head 24 and then enters the interior of the combustion chamber 1 through the liquid oxygen injection outlet 211.

[0089] like Figure 2 As shown, in some embodiments, the needle plug head 24 has multiple liquid oxygen injection outlets 211 arranged in a ring around the axis of the central rod 23. Each liquid oxygen injection outlet 211 is a strip-shaped hole with rounded ends, and its length is parallel to the axis of the central rod 23. The multiple liquid oxygen injection outlets 211 can be spaced apart circumferentially along the needle plug head 24. Each liquid oxygen injection outlet 211 communicates with a liquid oxygen injection channel 21, allowing liquid oxygen to enter the combustion chamber 1 from multiple circumferential positions of the needle plug head 24.

[0090] Continue to refer to Figure 1 The needle-plug injector 2 also includes an inner wall 25 of a kerosene channel surrounding the central rod 23. A first kerosene injection channel 22 is defined by the outer wall of the central rod 23 and the inner wall 25 of the kerosene channel. The first kerosene injection channel 22 extends along the outer periphery of the central rod 23 and forms a first kerosene injection outlet 221 near the needle-plug head 24. The first kerosene injection outlet 221 is positioned around the needle-plug head 24, and the first kerosene flows through the first kerosene injection channel 22 to the first kerosene injection outlet 221 before entering the interior of the combustion chamber 1.

[0091] like Figure 1 and Figure 3 As shown, the secondary injector 3 is fitted onto the outside of the combustion chamber 1. The inner peripheral wall of the secondary injector 3 and the outer peripheral wall of the combustion chamber 1 together define the kerosene chamber 31. The kerosene chamber 31 is arranged circumferentially around the combustion chamber 1. The secondary injector 3 is provided with a kerosene chamber inlet 33, which communicates with the kerosene chamber 31. Kerosene can enter the kerosene chamber 31 through the kerosene chamber inlet 33 and flow circumferentially along the kerosene chamber 31 within the combustion chamber 1.

[0092] The secondary injector 3 has a second kerosene injection channel 32. The second kerosene injection channel 32 connects the kerosene chamber 31 with the interior of the combustion chamber 1. After kerosene enters the kerosene chamber 31, it enters the interior of the combustion chamber 1 through the second kerosene injection channel 32. In some embodiments, the secondary injector 3 has multiple second kerosene injection channels 32, which are located at the same axial position in the combustion chamber 1 and are distributed circumferentially at intervals along the combustion chamber 1. All multiple second kerosene injection channels 32 are connected to the kerosene chamber 31 so that the kerosene in the kerosene chamber 31 can enter the multiple second kerosene injection channels 32 respectively.

[0093] Along the axial direction of combustion chamber 1, the outlet of the second kerosene injection channel 32 is located downstream of the first kerosene injection outlet 221. The centerline of the second kerosene injection channel 32 is inclined downstream relative to the axis of combustion chamber 1. Thus, the second kerosene injection channel 32 extends obliquely from the kerosene chamber 31 into the interior of combustion chamber 1. When the second kerosene enters combustion chamber 1 through the second kerosene injection channel 32, it enters the interior region of combustion chamber 1 downstream of the first kerosene injection outlet 221 along the extending direction of the second kerosene injection channel 32.

[0094] In some embodiments, the distance between the outlet of the second kerosene injection channel 32 and the inner bottom 11 along the axial direction of the combustion chamber 1 is 1 to 1.5 times the inner diameter of the combustion chamber 1. The angle between the centerline of the second kerosene injection channel 32 and the axis of the combustion chamber 1 is 30°. The outlet of the second kerosene injection channel 32 has a predetermined axial distance relative to the inner bottom 11, and the second kerosene injection channel 32 communicates with the interior of the combustion chamber 1 in an inclined direction.

[0095] In some embodiments, the kerosene flow rate injected into the combustion chamber 1 through the first kerosene injection channel 22 is greater than the kerosene flow rate injected into the combustion chamber 1 through the second kerosene injection channel 32. Further, the kerosene flow rate injected into the combustion chamber 1 through the second kerosene injection channel 32 can be 10% of the total kerosene flow rate injected into the combustion chamber 1 through the first and second kerosene injection channels 22. Under the rated operating conditions of the gas generator, the ratio of the liquid oxygen jet flow rate ejected from the liquid oxygen injection channel 21 to the kerosene jet flow rate ejected from the first kerosene injection channel 22 can be 2.

[0096] The following is combined with Figure 1 Explain the working process of a gas generator.

[0097] When the gas generator is operating, liquid oxygen enters the liquid oxygen injection channel 21 of the needle injector 2. The liquid oxygen flows along the liquid oxygen injection channel 21 to the needle head 24 and enters the interior of the combustion chamber 1 through the liquid oxygen injection outlet 211. First kerosene enters the first kerosene injection channel 22 of the needle injector 2. The first kerosene flows along the first kerosene injection channel 22 between the outer wall of the central rod 23 and the inner wall 25 of the kerosene channel, and enters the interior of the combustion chamber 1 through the first kerosene injection outlet 221 surrounding the needle head 24. After entering the combustion chamber 1 in the upstream region, the liquid oxygen and the first kerosene mix and burn inside the combustion chamber 1.

[0098] Simultaneously, the second kerosene enters the kerosene chamber 31 through the kerosene chamber inlet 33. After entering the kerosene chamber 31, the second kerosene flows circumferentially along the kerosene chamber 31 in the combustion chamber 1 and enters the second kerosene injection channel 32, which communicates with the kerosene chamber 31. In embodiments where the secondary injector 3 has multiple second kerosene injection channels 32, the kerosene chamber 31 distributes the second kerosene to the multiple second kerosene injection channels 32. The second kerosene then enters the interior of the combustion chamber 1 from different circumferential positions through the multiple second kerosene injection channels 32.

[0099] Since the outlet of the second kerosene injection channel 32 is located downstream of the first kerosene injection outlet 221, when the second kerosene enters the combustion chamber 1 through the second kerosene injection channel 32, it enters the internal region of the combustion chamber 1 downstream of the liquid oxygen and the first kerosene entry point. Because the centerline of the second kerosene injection channel 32 is inclined downstream relative to the axis of the combustion chamber 1, the second kerosene, after entering the combustion chamber 1 along the inclined direction, flows downstream along with the combustion gas within the combustion chamber 1. The combustion gas generated within the combustion chamber 1 flows downstream along the axial direction of the combustion chamber 1 and is discharged from the downstream end of the combustion chamber 1.

[0100] This application also provides a rocket propulsion device. The rocket propulsion device includes a turbopump and a gas generator as described in any of the foregoing embodiments. The exhaust port of the gas generator is connected to the intake port of the turbopump. When the gas generator is operating, the gas generated in the combustion chamber 1 enters the intake port of the turbopump through the exhaust port of the gas generator.

[0101] This application also provides a rocket. The rocket includes the gas generator of any of the foregoing embodiments, or includes the rocket propulsion device of the foregoing embodiments.

[0102] The description of the various embodiments above tends to emphasize the differences between the various embodiments. The similarities or similarities between them can be referred to, and for the sake of brevity, they will not be repeated here.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and not to limit them; although this application has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this application or equivalent substitutions can be made to some technical features, all of which should be covered within the scope of the technical solutions claimed in this application.

Claims

1. A gas generator, characterized in that, include: The combustion chamber is configured as a cylindrical structure extending axially, the combustion chamber having an upstream end and a downstream end; A needle-plug injector is disposed at the upstream end of the combustion chamber. The needle-plug injector includes a liquid oxygen injection channel and a first kerosene injection channel. The liquid oxygen injection channel extends axially along the combustion chamber to a liquid oxygen injection outlet. The first kerosene injection channel extends axially along the combustion chamber to a first kerosene injection outlet. The first kerosene injection outlet is arranged around the liquid oxygen injection outlet, and both the liquid oxygen injection outlet and the first kerosene injection outlet are in communication with the interior of the combustion chamber. A secondary injector is fitted onto the outside of the combustion chamber. The secondary injector has a second kerosene injection channel, which communicates with the interior of the combustion chamber. Along the axial direction of the combustion chamber, the outlet of the second kerosene injection channel is located downstream of the first kerosene injection outlet, and the centerline of the second kerosene injection channel is inclined downstream relative to the axis of the combustion chamber.

2. The gas generator according to claim 1, characterized in that, The inner peripheral wall of the secondary injector and the outer peripheral wall of the combustion chamber together define the kerosene chamber, which is arranged around the combustion chamber circumferentially. The second kerosene injection channel connects the kerosene chamber with the interior of the combustion chamber.

3. The gas generator according to claim 2, characterized in that, The secondary injector is provided with a kerosene chamber inlet communicating with the kerosene chamber. The kerosene chamber extends continuously along the circumference of the combustion chamber. The kerosene chamber is configured to distribute kerosene entering the kerosene chamber through the kerosene chamber inlet to the second kerosene injection channel.

4. The gas generator according to claim 3, characterized in that, The secondary injector has multiple second kerosene injection channels, which are located at the same axial position in the combustion chamber and are distributed circumferentially around the combustion chamber.

5. The gas generator according to claim 1, characterized in that, The kerosene flow rate injected into the combustion chamber through the first kerosene injection channel is greater than the kerosene flow rate injected into the combustion chamber through the second kerosene injection channel.

6. The gas generator according to claim 5, characterized in that, The kerosene flow rate injected into the combustion chamber through the second kerosene injection channel is 10% to 20% of the total kerosene flow rate injected into the combustion chamber through the first kerosene injection channel and the second kerosene injection channel.

7. The gas generator according to claim 1, characterized in that, The upstream end of the combustion chamber includes an inner bottom facing the interior of the combustion chamber, and the needle injector includes a central rod passing through the inner bottom along the axial direction of the combustion chamber and a needle head disposed near the downstream end of the central rod; the liquid oxygen injection channel is formed in the central rod and extends to the needle head, the needle head having the liquid oxygen injection outlet, and the liquid oxygen injection outlet is located upstream of the second kerosene injection channel along the axial direction of the combustion chamber.

8. The gas generator according to claim 7, characterized in that, The needle head has multiple liquid oxygen injection outlets, which are arranged in a ring around the axis of the central rod. Each liquid oxygen injection outlet is a strip-shaped hole with rounded ends, and the length direction of each liquid oxygen injection outlet is parallel to the axis of the central rod.

9. The gas generator according to claim 7, characterized in that, The distance between the outlet of the second kerosene injection channel and the inner bottom along the axial direction of the combustion chamber is 1 to 1.5 times the inner diameter of the combustion chamber.

10. The gas generator according to claim 7, characterized in that, The first kerosene injection channel is defined by the outer wall of the central rod and the inner wall of the kerosene channel surrounding the central rod, and the outlet of the first kerosene injection channel is arranged around the needle head.

11. The gas generator according to claim 1, characterized in that, The angle between the centerline of the second kerosene injection channel and the axis of the combustion chamber is 30° to 60°.

12. The gas generator according to claim 1, characterized in that, Under the rated operating conditions of the gas generator, the ratio of the liquid oxygen jet flow rate ejected from the liquid oxygen injection channel to the kerosene jet flow rate ejected from the first kerosene injection channel is 2 to 4.

13. A rocket propulsion system, characterized in that, It includes a turbopump and a gas generator as described in any one of claims 1 to 12, wherein the exhaust port of the gas generator is connected to the intake port of the turbopump.

14. A rocket, characterized in that, It includes a gas generator as described in any one of claims 1 to 12, or a rocket propulsion device as described in claim 13.

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