A fuel ramjet propulsion system and method

Abstract

The application belongs to the field of engine propulsion system, and particularly relates to a fuel ramjet propulsion system and method. The fuel ramjet propulsion system comprises a fuel tank and a self-pressurization control device; the fuel tank is arranged outside a high-temperature gas flow channel of an engine, and n partition plates are arranged in the fuel tank, which divide the fuel tank into n+1 sub-tank cabins along the engine axis, and a communication control valve for communicating adjacent sub-tank cabins is arranged on each partition plate; the self-pressurization control device comprises a pressurization part and a supply part. The application fully utilizes the advantages of easy gasification phase change and large heat sink of ammonia, and uses the technical method of ammonia self-pressurization to greatly reduce the complexity of the engine supply pipeline, get rid of additional devices such as fuel pumps and power batteries, and achieve the great simplification of the ramjet propulsion system through simple self-pressurization control, so as to meet the requirements of structure thermal protection and system use at a higher Mach number.

Description

Technical Field

[0001] This invention belongs to the field of engine propulsion systems, specifically relating to a fuel ramjet propulsion system and method. Background Technology

[0002] The primary function of a ramjet propulsion system is to provide reliable power for high-speed aircraft. Its core component is the air-breathing power plant, typically represented by the ramjet engine. During operation, the engine faces enormous thermal loads. At Mach 6, the total airflow temperature inside the combustion chamber can reach 2800K, and the heat flux on the engine walls can reach 3MW / m², far exceeding the limits of existing materials. Achieving reliable structural thermal protection has become a core bottleneck in advanced ramjet propulsion technology.

[0003] Fuel regeneration cooling has become the preferred solution to address the challenges of thermal protection for engine structures. Hydrocarbon fuel cracking heat sinks can reach 3.2 MJ / kg, barely meeting the engine thermal protection requirements for Mach 8 flights, but suffer from severe high-temperature coking and blockage of engine cooling channels. Ammonia (NH3), as a clean hydrogen-rich fuel, can also crack at high temperatures to produce pure, pollution-free nitrogen and hydrogen. The endothermic reaction can further increase the total heat sink to over 6 MJ / kg, meeting the cooling requirements for Mach 10 flights. It possesses heat release capacity comparable to hydrocarbon fuels and the advantage of zero carbon emissions, showing significant application potential in high Mach number propulsion. Currently, some organizations have proposed using hydrogen and ammonia as alternative fuels to traditional fossil fuels.

[0004] However, ammonia has a low critical temperature (405.6K), which is much lower than the structural temperature of a typical aero-engine, and a high critical pressure (11.28MPa), which is higher than the pressure required for conventional supply management. As a result, ammonia fuel is very prone to phase change after absorbing heat. To achieve a reliable fuel supply, a complex and redundant supply management and control system needs to be designed, which brings great difficulties to the fuel supply of actual engines. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a fuel ramjet propulsion system that makes full use of the advantages of ammonia's easy vaporization and phase change and large heat sink, and uses the ammonia self-pressurization technology to significantly reduce the complexity of the engine supply pipeline, eliminate the need for additional devices such as fuel pumps and power batteries, and achieve a significant simplification of the ramjet propulsion system through simple self-pressurization control, so as to meet the structural thermal protection and system use requirements of higher Mach numbers.

[0006] This invention provides a fuel ramjet propulsion system, including a fuel tank and a self-pressurization control device;

[0007] The fuel tank is located outside the high-temperature combustion gas flow passage of the engine, and there are n partition plates inside the fuel tank, where n is greater than or equal to 2. The n partition plates divide the fuel tank into n+1 sub-compartment tanks along the engine axis. Each partition plate is equipped with a connecting control valve that connects the adjacent sub-compartment tanks.

[0008] The self-pressurization control device includes a pressurization section and a supply section. The pressurization section includes an outlet branch, a heat exchange section and a pressurization branch connected in sequence. The outlet branch is connected to n+1 compartment storage tanks through a reversing valve I, and the pressurization branch is connected to n+1 compartment storage tanks through a reversing valve II. The heat exchange section exchanges heat with the high-temperature gas flow channel.

[0009] The supply section includes a main fuel line leading from the booster branch and a fuel control valve installed on the main fuel line. The outlet of the main fuel line is located in the combustion section or isolation section of the engine.

[0010] In one embodiment, an unloading valve is provided on the fuel tank.

[0011] In one embodiment, the heat exchange section is located upstream of the engine's regenerative cooling channel.

[0012] In one embodiment, the self-pressurization control device further includes a control unit;

[0013] The control unit includes a temperature sensor I, a pressure sensor I, a check valve I, and a flow meter installed on the outlet branch;

[0014] The control unit also includes a one-way valve II, a temperature sensor II, and a pressure sensor II installed on the booster branch;

[0015] The control unit also includes temperature sensor III and pressure sensor III installed on the fuel main line.

[0016] In one embodiment, the control unit further includes a temperature sensor IV and a pressure sensor IV disposed on the outlet branch near the inlet side of the heat exchange section.

[0017] In one embodiment, the self-boosting control device further includes a shut-off valve located upstream of the reversing valve II in the boosting branch.

[0018] In one embodiment, the engine includes a high-temperature gas flow channel, a thermal barrier coating, a regenerative cooling flow channel, an inner heat insulation layer, and an outer heat insulation layer arranged sequentially from the inside to the outside.

[0019] There is a gap between the inner and outer insulation layers, which forms a fuel tank.

[0020] In one embodiment, the partition plate is an annular plate, with the inner ring of the annular plate fixedly connected to the outer wall of the inner insulation layer and the outer ring fixedly connected to the inner wall of the outer insulation layer.

[0021] The present invention also provides a fuel ramjet propulsion method using the above-mentioned fuel ramjet propulsion system, including a fuel self-pressurization process and a fuel supply process;

[0022] The fuel self-pressurization process includes the following steps:

[0023] The n compartmentalized storage tanks include one commonly used variable pressure tank and n-1 spare constant pressure tanks;

[0024] S1, When the engine starts working, the heat exchange section absorbs the heat from the high-temperature gas flow channel wall to pressurize the fuel. The pressurized fuel flows into the normal pressure chamber after passing through the pressurization branch and reversing valve II in sequence, pressurizing the fuel in the normal pressure chamber. At this time, the fuel in the normal pressure chamber flows into the outlet branch through reversing valve I for circulation.

[0025] S2, when the commonly used pressure chamber reaches the set pressure, the pressure boosting branch and the outlet branch are connected to the next standby pressure chamber by controlling the reversing valve I and reversing valve II.

[0026] S3, when the standby pressure chamber reaches the set pressure, the booster branch and the outlet branch are connected to the commonly used pressure chamber by controlling the reversing valve I and reversing valve II.

[0027] S4, if n equals 2, then proceed to step S2;

[0028] If n is greater than 2, then repeat steps S2-S4 to pressurize n-1 spare pressure chambers in sequence.

[0029] In the entire fuel self-pressurization process, when the temperature of the high-temperature gas flow channel corresponding to the heat exchange section rises, the heat absorption of the heat exchange section increases, which strengthens the pressurization capacity of the compartment storage tank. At this time, the flow rate in the pressurization section increases, which cools down the heat exchange section corresponding to the high-temperature gas flow channel, and the heat absorption of the heat exchange section decreases. This cycle is repeated to achieve adaptive negative feedback regulation.

[0030] The fuel supply process includes the following steps:

[0031] When it is necessary to inject fuel into the high-temperature gas flow channel, the fuel control valve is opened, and the pressurized fuel flows into the high-temperature gas flow channel through the fuel main line.

[0032] In one embodiment, in the fuel self-pressurization process, by determining the set pressure and set temperature of each compartment storage tank, corresponding cooling is achieved at different locations in the high-temperature gas flow channel.

[0033] The beneficial effects of this invention are as follows: 1. The structural arrangement of the fuel tank allows for the division of the tank space, reducing the volume of individual compartment tanks and enabling higher pressure for the pressurized gas per unit flow rate, thus improving the efficiency of the pressurization branch in controlling the pressure within the compartment tanks. 2. The compartment tanks allow for differentiated fuel temperatures within different compartments. Since the compartment tanks surround the high-temperature gas flow channel, they act as a cold source absorbing structural heat. When overpressure is imminent within a compartment tank, the opening of the interconnection control valves disperses pressure and lowers the temperature, reducing the risk of overpressure and fuel loss. 3. The partitions formed by the compartments act as structural reinforcement, enhancing the load-bearing capacity of the fuel tank as a major structure of the propulsion system. 4. When the set pressures of multiple compartment tanks are inconsistent, the fuel supply process can be optimized by selecting a compartment tank with a specific pressure, achieving a certain degree of adaptive adjustment to flight conditions.

[0034] 2. The arrangement of the self-pressurization control device enables fuel pressurization using ambient passive heat sources without the need for external heating devices or additional power supplies, significantly reducing electricity demand and even achieving operation without electricity. This greatly simplifies the fuel process and control devices required by traditional propulsion systems, reducing the weight and space required for the supply unit, which is of great significance for simplifying the propulsion system design and reducing costs. Simultaneously, the self-pressurization control device can also achieve adaptive negative feedback regulation; that is, it can adaptively adjust flow rate, pressure, and temperature without manual intervention, maintaining a dynamic balance between the temperature and pressurization pressure at the corresponding locations in the high-temperature gas flow channel and the heat exchange section.

[0035] 3. The self-pressurization control device maintains the set pressure in the commonly used pressure chamber, solving the problem of pressure gradually decreasing over time and allowing for rapid supply of fuel to the supply unit at the required pressure, ensuring timely fuel supply. While maintaining the set pressure in the commonly used pressure chamber, n-1 standby pressure chambers can be pressurized sequentially, fully utilizing passive heat sources in the environment. This is achieved by flexibly adjusting the reversing valves to pressurize different compartments, enabling flexible adjustment across a wide range of operating conditions.

[0036] 4. The interconnection control valve serves several purposes. First, when the pressure in a particular compartment is too high, it can quickly release pressure from adjacent compartments. Since these adjacent compartments are not under pressure, their pressure is likely lower than the set pressure. This allows for both depressurization of the pressurized compartment and pressurization of adjacent compartments with pressures below the set pressure. Second, it can connect all compartments, integrating them into a unified system. Third, the interconnection control valve allows fuel flow, coordinating fuel reserves within the compartments. This ensures proper weight distribution in the ramjet propulsion system and effective temperature control of the high-temperature gas flow channels throughout the fuel usage process. Attached Figure Description

[0037] Appendix Figure 1 This is a schematic diagram of the structure of the present invention;

[0038] Appendix Figure 2 This is a radial sectional view of the present invention;

[0039] Appendix Figure 3 This is a schematic diagram of the self-pressurization control device in this invention;

[0040] Appendix Figure 4 This is a schematic diagram of the adaptive negative feedback adjustment process in this invention.

[0041] In the diagram, 1-fuel tank; 11-partition plate; 12-compartment tank; 12a-compartment tank A; 12b-compartment tank B; 12c-compartment tank C; 12d-compartment tank D; 13-connection control valve; 14-unloading valve; 2-self-pressurization control device; 21-outlet branch; 211-temperature sensor I; 212-pressure sensor I; 213-check valve I; 214-flow meter; 215-temperature sensor IV; 216-pressure sensor IV; 22-heat exchange section; 23- Boosting branch; 231-One-way valve II; 232-Temperature sensor II; 233-Pressure sensor II; 24-Reversing valve II; 25-Reversing valve I; 26-Main fuel line; 261-Fuel control valve; 262-Temperature sensor III; 263-Pressure sensor III; 27-Integrated controller; 28-Stop valve; 3-Engine; 31-High-temperature gas flow channel; 311-Combustion section; 32-Thermal barrier coating; 33-Regenerative cooling flow channel; 34-Inner insulation layer; 35-Outer insulation layer; 4-Fuel. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0043] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0044] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0045] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection, an electrical connection, a physical connection, or a wireless communication connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two elements or the interaction between two elements, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0046] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0047] As attached Figure 1 -Appendix Figure 4 As shown, the present invention provides a fuel ramjet propulsion system, including a fuel tank 1 and a self-pressurization control device 2;

[0048] The fuel tank 1 is disposed outside the high-temperature combustion gas flow passage 31 of the engine 3, wherein, reference Figure 1 The high-temperature gas flow channel 31 includes an intake section, an isolation section, a combustion section 311, and a nozzle arranged sequentially. The fuel tank 1 can be arranged along the entire axial length of the high-temperature gas flow channel 31, or it can be arranged in a portion of the channel. This arrangement can make full use of the space of the fuel ramjet propulsion system, reduce the weight and space required by the fuel tank 1, and is of great significance for simplifying the propulsion system design and reducing costs. Furthermore, the fuel tank 1 is provided with n partition plates 11, where n is greater than or equal to 2. The n partition plates 11 divide the fuel tank 1 along the axial direction of the engine 3 into n+1 sub-compartment tanks 12. Each partition plate 11 is provided with a connection control valve 13 that connects adjacent sub-compartment tanks 12. The connection control valve 13 can control the connection and isolation between two adjacent sub-compartment tanks 12.

[0049] The self-pressurization control device 2 includes a pressurization section and a supply section. The pressurization section includes an outlet branch 21, a heat exchange section 22, and a pressurization branch 23 connected in sequence. The outlet branch 21 is connected to n+1 sub-compartment storage tanks 12 via a reversing valve I 25. That is, the reversing valve I 25 can control the outlet branch 21 to connect with one of the sub-compartment storage tanks 12, and disconnect it from the other sub-compartment storage tanks 12 when connected to one of the sub-compartment storage tanks 12. The pressurization branch 23 is connected to n+1 sub-compartment storage tanks 12 via a reversing valve II 24. That is, the reversing valve II 24 can control the pressurization branch 23 to connect with one of the sub-compartment storage tanks 12, and disconnect it from the other sub-compartment storage tanks 12 when connected to one of the sub-compartment storage tanks 12. The heat exchange section 22 exchanges heat with the high-temperature gas flow channel 31; wherein, the heat exchange section 22 can be directly installed on the wall of the high-temperature gas flow channel 31 of the engine 3, or it can be installed on the regenerative cooling flow channel 33 of the engine 3 to exchange heat with the medium in the regenerative cooling flow channel 33, or it can be the regenerative cooling flow channel 33 itself.

[0050] The supply unit includes a main fuel line 26 extending from the pressurization branch line 23 and a fuel control valve 261 installed on the main fuel line 26. The outlet of the main fuel line 26 is located in the combustion section 311 or isolation section of the engine 3. The supply unit is used to supply fuel from the pressurized compartment storage tank 12 to the combustion section 311 or isolation section of the engine 3.

[0051] The fuel ramjet propulsion system provided by this invention can perform the following fuel ramjet propulsion method:

[0052] This includes the fuel self-pressurization process and the fuel supply process;

[0053] The fuel self-pressurization process includes the following steps:

[0054] The n compartmentalized storage tanks 12 include one commonly used variable pressure tank and n-1 spare constant pressure tanks;

[0055] S1, when the engine 3 starts working, the heat exchange section 22 absorbs the heat from the wall of the high-temperature gas flow channel 31 (it can directly absorb the heat from the wall of the high-temperature gas flow channel 31, or indirectly absorb the heat from the wall of the high-temperature gas flow channel 31 through the regeneration cooling flow channel 33) to pressurize the fuel 4 located in the pressurization section. The pressurized fuel 4 flows into the normal pressure chamber after passing through the pressurization branch 23 and the reversing valve II 24 in sequence, pressurizing the fuel 4 in the normal pressure chamber. At this time, the fuel 4 in the normal pressure chamber flows into the outlet branch 21 through the reversing valve I 25 for circulation.

[0056] S2, when the pressure chamber reaches the set pressure, the pressure boosting branch 23 and the outlet branch 21 are connected to the next standby pressure chamber by controlling the reversing valve I 25 and the reversing valve II 24.

[0057] S3, when the standby pressure chamber reaches the set pressure, the booster branch 23 and the outlet branch 21 are connected to the normal pressure chamber by controlling the reversing valve I 25 and the reversing valve II 24.

[0058] S4, if n equals 2, then proceed to step S2;

[0059] If n is greater than 2, then repeat steps S2-S4 to pressurize n-1 spare pressure chambers in sequence.

[0060] The above steps ensure that the pressure in the commonly used transformer tank remains at the set pressure, resolving the issue of pressure gradually decreasing over time. This allows for the rapid supply of fuel 4 at the required pressure to the supply unit, guaranteeing timely fuel supply. While maintaining the set pressure in the commonly used transformer tank, n-1 standby pressure tanks can be pressurized sequentially, fully utilizing passive heat sources in the environment. This is achieved by flexibly adjusting the reversing valves to pressurize different compartment storage tanks 12, enabling flexible adjustment across a wide range of operating conditions.

[0061] The commonly used pressure chamber does not use a specific compartment storage tank 12. It can be switched as needed. For example, when the fuel reserve in a certain compartment storage tank 12 is too low, other compartment storage tanks 12 can be replaced as the commonly used pressure chamber.

[0062] The interconnection control valve 13 serves several purposes. First, when the pressure in a particular compartment tank 12 becomes too high, it can quickly release pressure from adjacent compartment tanks 12. Simultaneously, since the adjacent compartment tanks 12 are not in a pressurized state, their pressure is likely lower than the set pressure. This allows for both depressurization of the pressurized compartment tank 12 and pressurization of adjacent compartment tanks 12 with pressures below the set pressure. Second, it can connect all compartment tanks 12, making them a unified whole. Third, it allows fuel 4 to flow through the interconnection control valve 13, thus coordinating the fuel reserves within the compartment tanks 12. This ensures the weight distribution of the fuel-powered ramjet propulsion system and the temperature control effect of the compartment tanks 12 on the high-temperature gas flow channel 31 throughout the fuel usage process.

[0063] Reference Appendix Figure 4 In the entire fuel self-pressurization process, when the temperature of the high-temperature gas flow channel 31 corresponding to the heat exchange section 22 increases, the heat absorption of the heat exchange section 22 increases, and the pressurization capacity of the compartment storage tank 12 is enhanced. At this time, the flow rate in the pressurization section increases, which cools the position of the heat exchange section 22 corresponding to the high-temperature gas flow channel 31, and the heat absorption of the heat exchange section 22 decreases. This cycle is repeated to achieve adaptive negative feedback regulation. That is, the flow rate, pressure and temperature can be adaptively regulated without manual intervention, so that the temperature and pressurization pressure of the corresponding position of the high-temperature gas flow channel 31 and the heat exchange section 22 are kept in dynamic balance.

[0064] The fuel supply process includes the following steps:

[0065] When it is necessary to inject fuel 4 into the high-temperature gas flow channel 31, the fuel control valve 261 is opened, and the pressurized fuel 4 flows into the high-temperature gas flow channel 31 through the fuel main line 26.

[0066] Preferably, during the fuel supply process, the booster branch 23 can be closed by using directional valve II 24 or shut-off valve 28 located on the main fuel line 26; and the booster branch 23 and the outlet branch 21 can be connected to the normal pressure chamber by controlling directional valve I 25 and directional valve II 24, so that fuel 4 can be supplied from the normal pressure chamber. When there is sufficient heat, the fuel supply process and the fuel self-pressurization process can also be carried out simultaneously.

[0067] Preferably, when the set pressures of multiple compartment tanks 12 are inconsistent, the fuel supply process can be carried out by selecting a compartment tank 12 with a specific pressure, which can achieve a certain degree of adaptive adjustment of flight conditions.

[0068] In one embodiment, during the fuel self-pressurization process, the set pressure and set temperature of each compartment storage tank 12 can be determined to achieve corresponding cooling at different locations of the high-temperature gas flow channel 31. That is, since multiple compartment storage tanks 12 are located outside the high-temperature gas flow channel 31, the combination of the pressurization unit and multiple compartment storage tanks 12 can also be used for active axial temperature control of the high-temperature gas flow channel 31.

[0069] The fuel ramjet propulsion system of the present invention has the following beneficial effects;

[0070] 1. The structural arrangement of the fuel tank 1 serves several purposes: First, it allows for the division of the tank space, reducing the volume of individual compartment tanks 12 and enabling higher pressure for the pressurized gas per unit flow rate, thereby improving the efficiency of the pressurization branch 23 in controlling the pressure within the compartment tanks 12. Second, it allows for differentiated fuel temperatures within different compartments of the compartment tanks 12. Since the compartment tanks 12 surround the high-temperature gas flow channel 31, they act as a cold source absorbing structural heat. When overpressure is imminent within a compartment tank 12, the opening of the connecting control valve 13 disperses pressure and lowers the temperature, reducing the risk of overpressure and fuel loss. Third, the partition plates 11 formed by the compartments serve as structural reinforcement, enhancing the load-bearing capacity of the fuel tank 1 as the main structure of the propulsion system. Fourth, when the set pressures of multiple compartment tanks 12 are inconsistent, the fuel supply process can be optimized by selecting a compartment tank 12 with a specific pressure, achieving a certain degree of adaptive adjustment to flight conditions.

[0071] 2. The arrangement of the self-pressurization control device 2 enables the pressurization of fuel 4 using a passive environmental heat source without the need for external heating devices or additional power supplies, significantly reducing electricity demand and even achieving operation without electricity. This greatly simplifies the fuel process and control devices required by traditional propulsion systems, reduces the weight and space required for the supply unit, and is of great significance for simplifying the propulsion system design and reducing costs. Simultaneously, the self-pressurization control device 2 can also achieve adaptive negative feedback regulation; that is, it can achieve adaptive regulation of flow rate, pressure, and temperature without manual intervention, maintaining a dynamic balance between the temperature and pressurization pressure at the corresponding locations in the high-temperature gas flow channel 31 and the heat exchange section 22.

[0072] 3. The pressurization method of the self-pressurization control device 2 can continuously maintain the set pressure in the commonly used pressure chamber, solving the problem of the pressure in the commonly used pressure chamber gradually decreasing over time, and thus quickly providing the required pressure of fuel 4 to the supply unit, ensuring timely fuel supply. While maintaining the set pressure of the commonly used pressure chamber, n-1 standby pressure chambers can be pressurized sequentially, thereby making full use of passive heat sources in the environment. That is, by flexibly adjusting the reversing valves to pressurize different compartment storage tanks 12, flexible adjustment over a wide range of operating conditions can be achieved.

[0073] 4. The connection control valve 13 serves several purposes. First, when the pressure in a particular compartment tank 12 becomes too high, it can quickly release pressure from adjacent compartment tanks 12. Simultaneously, since the adjacent compartment tanks 12 are not in a pressurized state, their pressure is likely lower than the set pressure. This allows for both depressurization of the pressurized compartment tank 12 and pressurization of adjacent compartment tanks 12 with pressures below the set pressure. Second, it can connect all compartment tanks 12, making them a unified whole. Third, it allows fuel to flow through the connection control valve 13, thus coordinating the fuel reserves within the compartment tanks 12. This ensures the weight distribution of the fuel-powered ramjet propulsion system and the temperature control effect of the compartment tanks 12 on the high-temperature gas flow channel 31 throughout the fuel usage process.

[0074] In one specific embodiment, refer to the appendix. Figure 1 n equals 4. Four partition plates 11 divide the fuel tank 1 into four compartments 12 along the engine 3 axis, front and back: compartment A 12a, compartment B 12b, compartment C 12c, and compartment D 12d. Among them, compartment A 12a is the commonly used pressure changing chamber, and compartment B 12b, compartment C 12c, and compartment D 12d are the spare pressure changing chambers.

[0075] The set pressures of compartment A tank 12a, compartment B tank 12b, compartment C tank 12c, and compartment D tank 12d are 3 MPa, 5 MPa, and 7 MPa respectively, to ensure the sustained and stable pressure of compartments C and D. This guarantees a fuel supply that meets the required pressure at any given time. Furthermore, by selecting compartments 12 with specific pressures for the fuel supply process, a degree of adaptive adjustment to flight conditions can be achieved.

[0076] Preferably, fuel 4 is ammonia fuel. Ammonia fuel exists in two phases, which can make full use of the phase interface. By introducing high-temperature and high-pressure ammonia gas to pressurize the compartment storage tank 12, the pressure inside the compartment storage tank 12 is slowly reduced by utilizing the delayed characteristics of high-temperature gas heat exchange. By dynamically controlling the tank pressure, a self-pressurizing propulsion system with adaptive fuel flow under simple open-loop control is realized.

[0077] In one embodiment, an unloading valve 14 is provided on the fuel tank 1. Preferably, each compartment tank 12 is provided with an unloading valve 14. When the pressure of the compartment tank 12 approaches the structural bearing limit of the engine 3, the unloading valve 14 automatically opens to discharge excess gas, thereby controlling the tank pressure within a safe range, typically set to 8 MPa. Alternatively, only one compartment tank 12 may be provided with an unloading valve 14. Through the control of the connecting control valve 13, any compartment tank 12 can be connected to the unloading valve 14.

[0078] Considering the need to avoid affecting the thermal protection requirements of critical structural components of engine 3 and the accurate monitoring of nozzle flow (located at the outlet side of the main fuel line 26), the heat exchange section 22 requires special installation to both absorb a certain amount of heat for pressurization and form negative feedback regulation. In one embodiment, the heat exchange section 22 is located upstream of the regenerative cooling channel 33 of engine 3. In this case, the liquid temperature rise within the heat exchange section 22 does not exceed 100°C.

[0079] In one embodiment, reference Figure 3 The self-pressurization control device 2 also includes a control unit, which is used to coordinate the negative feedback regulation and the control and switching of the fuel self-pressurization process and the fuel supply process.

[0080] The control unit includes a temperature sensor I211, a pressure sensor I212, a one-way valve I213, and a flow meter 214 installed on the outlet branch 21; wherein the temperature sensor I211 is used to monitor the flow temperature in the compartment storage tank 12; the pressure sensor I212 is used to monitor the flow pressure in the compartment storage tank 12; the one-way valve I213 is used to control the unidirectional flow of fuel 4 in the outlet branch 21; and the flow meter 214 is used to monitor the flow rate of the outlet branch 21.

[0081] The control unit also includes a one-way valve II 231, a temperature sensor II 232, and a pressure sensor II 233 installed on the booster branch 23; the one-way valve II 231 is used to control the unidirectional flow of fuel 4 in the booster branch 23; the temperature sensor II 232 is used to monitor the booster flow temperature in the booster branch 23; and the pressure sensor II 233 is used to monitor the booster flow pressure in the booster branch 23.

[0082] The control unit also includes a temperature sensor Ⅲ262 and a pressure sensor Ⅲ263 installed on the fuel main line 26; the temperature sensor Ⅲ262 is used to monitor the pre-injection flow temperature in the fuel main line 26; the pressure sensor Ⅲ263 is used to monitor the pre-injection flow pressure in the fuel main line 26.

[0083] Temperature sensor I 211, pressure sensor I 212, flow meter 214, temperature sensor II 232, pressure sensor II 233, temperature sensor III 262, and pressure sensor III 263 are all connected to the integrated controller 27. Directional control valve I 25, directional control valve II 24, and fuel control valve 261 are also connected to the integrated controller 27. This enables integrated control based on sensor data through the integrated controller 27.

[0084] In one embodiment, the control unit further includes a temperature sensor IV215 and a pressure sensor IV216 disposed on the outlet branch 21 near the inlet side of the heat exchange section 22; the temperature sensor IV215 is used to monitor the inlet flow temperature of the heat exchange section 22; the pressure sensor IV216 is used to monitor the inlet flow pressure of the heat exchange section 22; the temperature sensor IV215 and the pressure sensor IV216 are connected to the integrated controller 27.

[0085] In one embodiment, the self-pressurization control device 2 further includes a shut-off valve 28 disposed upstream of the reversing valve II 24 in the pressurization branch 23, and the shut-off valve 28 is also connected to the integrated controller 27. The shut-off valve 28 is used to control the opening and closing of the pressurization branch 23, thereby ensuring that all fuel 4 flows into the combustion section 311 or the isolation section through the fuel main line 26 during the fuel supply process.

[0086] In one embodiment, reference is made to the appendix. Figure 2 The engine 3 includes, from the inside out, a high-temperature gas flow channel 31, a thermal barrier coating 32, a regenerative cooling flow channel 33, an inner heat insulation layer 34, and an outer heat insulation layer 35; there is a gap between the inner heat insulation layer 34 and the outer heat insulation layer 35, forming a fuel tank 1. In this embodiment, the radial space of the engine 3 can be fully utilized. The heat insulation rate of the inner heat insulation layer 34 can be selected as needed, that is, it can exchange heat with the high-temperature gas flow channel 31.

[0087] In one embodiment, the partition plate 11 is an annular plate, with its inner ring fixedly connected to the outer wall of the inner heat insulation layer 34 and its outer ring fixedly connected to the inner wall of the outer heat insulation layer 35. This configuration significantly enhances the radial structural strength of the engine 3.

[0088] The above description is merely an embodiment and does not constitute any limitation on the present invention. Any person skilled in the art can make many possible variations, modifications, or alterations to the technical solutions of the present invention without departing from the scope of the present invention. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention, without departing from the scope of the present invention, should fall within the protection scope of the present invention.

Claims

1. A fuel ramjet propulsion system, characterized in that, Includes a fuel tank (1) and a self-pressurization control device (2); The fuel tank (1) is arranged around the high-temperature gas flow channel (31) of the engine (3), and the fuel tank (1) is provided with n partition plates (11), n ​​is greater than or equal to 2. The n partition plates (11) divide the fuel tank (1) into n+1 compartment tanks (12) along the engine (3) axis. Each partition plate (11) is provided with a connecting control valve (13) that connects the adjacent compartment tanks (12). The self-pressurization control device (2) includes a pressurization section and a supply section. The pressurization section includes an outlet branch (21), a heat exchange section (22), and a pressurization branch (23) connected in sequence. The outlet branch (21) is connected to n+1 compartment storage tanks (12) through a reversing valve I (25). The pressurization branch (23) is connected to n+1 compartment storage tanks (12) through a reversing valve II (24). The heat exchange section (22) exchanges heat with the high-temperature gas flow channel (31). The supply section includes a fuel main line (26) led out from the booster branch (23) and a fuel control valve (261) installed on the fuel main line (26). The outlet of the fuel main line (26) is located in the combustion section (311) or isolation section of the engine (3).

2. The fuel ramjet propulsion system as described in claim 1, characterized in that, An unloading valve (14) is installed on the fuel tank (1).

3. The fuel ramjet propulsion system as described in claim 1, characterized in that, The heat exchange section (22) is located upstream of the regeneration cooling channel (33) of the engine (3).

4. The fuel ramjet propulsion system as described in any one of claims 1-3, characterized in that, The self-pressurization control device (2) also includes a control unit; The control unit includes a temperature sensor I (211), a pressure sensor I (212), a check valve I (213), and a flow meter (214) installed on the outlet branch (21). The control unit also includes a one-way valve II (231), a temperature sensor II (232), and a pressure sensor II (233) installed on the booster branch (23); The control unit also includes a temperature sensor III (262) and a pressure sensor III (263) installed on the fuel main line (26).

5. The fuel ramjet propulsion system as described in claim 4, characterized in that, The control unit also includes a temperature sensor IV (215) and a pressure sensor IV (216) located on the outlet branch (21) near the inlet side of the heat exchange section (22).

6. The fuel ramjet propulsion system as described in claim 4, characterized in that, The self-boosting control device (2) also includes a shut-off valve (28) located upstream of the reversing valve II (24) in the boosting branch (23).

7. The fuel ramjet propulsion system as described in any one of claims 1-3, 5, and 6, characterized in that, The engine (3) includes a high-temperature gas flow channel (31), a thermal barrier coating (32), a regenerative cooling flow channel (33), an inner heat insulation layer (34), and an outer heat insulation layer (35) arranged sequentially from the inside to the outside. There is a gap between the inner insulation layer (34) and the outer insulation layer (35), which forms a fuel tank (1).

8. The fuel ramjet propulsion system as described in claim 7, characterized in that, The partition plate (11) is an annular plate. The inner ring of the annular plate is fixedly connected to the outer wall of the inner insulation layer (34), and the outer ring is fixedly connected to the inner wall of the outer insulation layer (35).

9. A fuel ramjet propulsion method, characterized in that, Using the fuel ramjet propulsion system as described in any one of claims 1-8, including a fuel self-pressurization process and a fuel supply process; The fuel self-pressurization process includes the following steps: The n compartmentalized storage tanks (12) include one commonly used variable pressure tank and n-1 spare constant pressure tanks; S1, When the engine (3) starts working, the heat exchange section (22) absorbs the heat from the wall of the high-temperature gas flow channel (31) to pressurize the fuel (4). The pressurized fuel (4) flows into the common pressure chamber after passing through the pressurization branch (23) and the reversing valve II (24) in sequence, pressurizing the fuel (4) in the common pressure chamber. At this time, the fuel (4) in the common pressure chamber flows into the outlet branch (21) through the reversing valve I (25) for circulation. S2, when the pressure chamber reaches the set pressure, the pressure boosting branch (23) and the outlet branch (21) are connected to the next standby pressure chamber by controlling the reversing valve I (25) and the reversing valve II (24); S3, when the standby pressure chamber reaches the set pressure, the pressure boosting branch (23) and the outlet branch (21) are connected to the commonly used pressure chamber by controlling the reversing valve I (25) and the reversing valve II (24); S4, if n equals 2, then proceed to step S2; If n is greater than 2, then repeat steps S2-S4 to pressurize n-1 spare pressure chambers in sequence. In the entire fuel self-pressurization process, when the temperature of the high-temperature gas flow channel (31) corresponding to the heat exchange section (22) rises, the heat absorption of the heat exchange section (22) increases, and the pressurization capacity of the compartment storage tank (12) is strengthened. At this time, the flow rate in the pressurization section increases, and the position of the heat exchange section (22) corresponding to the high-temperature gas flow channel (31) is cooled down, and the heat absorption of the heat exchange section (22) decreases. This cycle is repeated to achieve adaptive negative feedback regulation. The fuel supply process includes the following steps: When it is necessary to inject fuel (4) into the high-temperature gas flow channel (31), the fuel control valve (261) is opened, and the pressurized fuel (4) flows into the high-temperature gas flow channel (31) through the fuel main line (26).

10. The fuel ramjet propulsion method as described in claim 9, characterized in that, In the fuel self-pressurization process, by determining the set pressure and set temperature of each compartment storage tank (12), corresponding cooling is achieved at different positions of the high-temperature gas flow channel (31).

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