A cryogenic propellant cross-pressurization delivery system and parallel rocket

Abstract

The embodiment of the present invention provides a cryogenic propellant cross-boosting and conveying system and a parallel rocket, including multiple sets of boosting and conveying units, each set of boosting and conveying units includes a liquid oxygen tank and a cryogenic propellant tank, the liquid phase spaces of each liquid oxygen tank are interconnected, the liquid phase spaces of each cryogenic propellant tank are interconnected, the gas phase spaces of each liquid oxygen tank are interconnected, and the gas phase spaces of each cryogenic propellant tank are interconnected. In this technical solution, the liquid oxygen level and the cryogenic propellant level in multiple sets of boosting and conveying units can be guaranteed to be consistent, so as to ensure that the fuel in each tank is consumed at the same time, reduce the safety margin of the remaining fuel, reduce the dead weight of the rocket, and thus improve the carrying capacity of the rocket; at the same time, since the air pillow pressure of each liquid oxygen tank is the same and the air pillow pressure of each cryogenic propellant tank is also the same, the safety valve can be shared, thereby reducing the cost.

Description

Technical Field

[0001] The present invention relates to the technical field of rocket engines, and in particular to a cryogenic propellant cross-pressurization delivery system and a parallel rocket. Background Art

[0002] At present, the demands of major space powers for Earth-Moon, Earth-Mars and other deep space exploration missions are increasing. With the development of space technology industrialization and commercialization, research on "green", low-cost, highly reliable large and heavy-duty launch vehicles has become a hot topic. In this process, strap-on rockets have been increasingly used. Strapped rockets refer to each stage of the rocket assembly, which is equipped with multiple rocket bodies (including core stage and booster stage), and each rocket body is equipped with an independent pressurization and delivery system to increase thrust and improve carrying capacity.

[0003] In the process of implementing the present invention, the inventors found that there are at least the following problems in the prior art:

[0004] At the current stage of launch vehicle development, simply increasing the amount of fuel carried will inevitably also significantly increase the rocket's own weight. It is difficult to achieve greater breakthroughs in this way. Therefore, how to improve the pressurization and delivery system based on the overall structure of the existing rocket, achieve power redundancy, and improve the rocket's carrying capacity is a problem that needs to be solved. Summary of the invention

[0005] The embodiment of the present invention provides a cryogenic propellant cross-pressurization delivery system and a parallel rocket, which are used to improve the carrying capacity of the rocket.

[0006] To achieve the above-mentioned purpose, on the one hand, an embodiment of the present invention provides a cryogenic propellant cross-pressurization and delivery system, comprising a plurality of sets of pressurization and delivery units, each set of the pressurization and delivery units comprising a liquid oxygen tank and a cryogenic propellant tank, the liquid phase spaces of the liquid oxygen tanks being interconnected through a liquid oxygen tank cross-delivery pipeline, and the liquid phase spaces of the cryogenic propellant tanks being interconnected through a propellant tank cross-delivery pipeline.

[0007] On the other hand, an embodiment of the present invention further provides a parallel rocket, wherein the first-stage assembly of the parallel rocket is provided with the aforementioned cryogenic propellant cross-pressurization and delivery system; the first-stage assembly of the parallel rocket includes a core first-stage rocket body, and two booster first-stage rocket bodies arranged on the sides of the core first-stage rocket body; a set of pressurization and delivery units are respectively provided on the core first-stage rocket body and each of the booster first-stage rocket bodies.

[0008] The above technical solution has the following beneficial effects:

[0009] The technical solution of the present invention adopts a cross-pressurization and delivery method, that is, by connecting the liquid phase space of the liquid oxygen tank of multiple sets of pressurization and delivery systems, connecting the liquid phase space of the propellant tank, and at the same time connecting the air pillow part of the liquid oxygen tank and the air pillow part of the propellant tank, it can be ensured that the air pillow pressure and liquid level in the corresponding tanks (including liquid oxygen tanks and cryogenic propellant tanks) in the multiple systems are the same, thereby ensuring that the fuel in each tank is consumed at the same time, avoiding the problem of large remaining amount caused by inconsistent liquid levels in the corresponding tanks at the shutdown time that often occurs in the prior art, thereby effectively reducing the safety margin of the remaining fuel, thereby reducing the dead weight of the rocket and improving the carrying capacity of the rocket.

[0010] In addition, this technical solution also has the following characteristics:

[0011] 1) Since multiple boost and delivery systems are cross-connected in parallel, when an engine in a rocket body shuts down unexpectedly due to a fault, the cross-boost and delivery method can be used to transfer the remaining fuel in the faulty rocket body to other normal rocket bodies for use, thereby achieving full utilization of fuel and power redundancy.

[0012] 2) At the same time, in the cross-pressurization mode of this embodiment, the air pillow pressures of each liquid oxygen tank are the same, and the air pillow pressures of each cryogenic propellant tank are also the same. Therefore, the liquid oxygen tank safety valve can be shared, and the propellant tank safety valve can also be shared. Only one is required for each, thereby reducing the number of safety valves and reducing costs.

[0013] 3) Both the liquid oxygen tank and the cryogenic propellant tank adopt an open self-pressurization scheme. The system is simple and reliable and has low dependence on the control system. It not only improves the reliability, but also reduces the difficulty of system development, the production cost of the system, and shortens the product matching cycle.

[0014] 4) In the embodiment of the present invention, a mechanical safety valve is used to control the air pillow pressure of the oxygen tank and the cryogenic propellant tank. According to simulation calculation, the safety valves of the oxygen tank and the cryogenic propellant tank are opened 4 to 5 times. This opening number is small, which can meet the life requirement of the safety valve and prevent the problem of insufficient boost pressure caused by calculation and simulation deviations. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 This is a system principle diagram of a cryogenic propellant cross-pressurization delivery system according to an embodiment of the present invention;

[0017] Figure 2 This is a system principle diagram of a parallel rocket according to an embodiment of the present invention;

[0018] Figure 3 It is a schematic diagram of the structure of a multi-pass in a specific embodiment of the present invention;

[0019] Figure 4 It is a diagram of the oxygen box air pillow pressure and other pressure distributions in a specific embodiment of the present invention;

[0020] Figure 5 It is a diagram of the pressure of the cryogenic propellant tank air pillow and other pressure distributions in a specific embodiment of the present invention;

[0021] Figure numbers: 1. Liquid oxygen tank; 2. Cryogenic propellant tank; 3. Engine; 4. Oxygen self-generating supercharger; 5. Oxygen self-pressurizing pipeline; 6. First three-way; 7. Liquid oxygen tank energy dissipator; 8. Liquid oxygen tank safety valve; 9. Propellant self-generating supercharger; 10. Propellant self-pressurizing pipeline; 11. Propellant tank energy dissipator; 12. Propellant tank top interface; 13. Propellant tank safety valve; 14. Liquid oxygen tank bottom interface; 15. Propellant tank bottom interface; 16. Liquid Oxygen delivery main line; 17. Propellant tank tunnel pipe; 18. Liquid oxygen delivery multi-way; 19. Liquid oxygen branch delivery pipe; 20. Liquid oxygen tank cross-pressurization pipeline; 21. Liquid oxygen tank cross-delivery pipeline; 22. Propellant tank cross-pressurization pipeline; 23. Propellant tank cross-delivery pipeline; 24. Second three-way; 25. Third three-way; 26. Fourth three-way; 27. Fifth three-way; 28. Liquid oxygen pump inlet; 100. Core first stage rocket body; 200. Booster first stage rocket body. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] like Figure 1 As shown, an embodiment of the present invention provides a cryogenic propellant cross-pressurization and delivery system, including multiple sets of pressurization and delivery units, each set of pressurization and delivery units includes a liquid oxygen tank 1 and a cryogenic propellant tank 2, the liquid phase spaces of the liquid oxygen tank 1 are interconnected through a liquid oxygen tank cross-delivery pipeline 21, and the liquid phase spaces of the cryogenic propellant tank 2 are interconnected through a propellant tank cross-delivery pipeline 23.

[0024] The inventors have found that although the bundled rocket has multiple rocket bodies and can greatly improve the carrying capacity, there is always a problem of a large amount of fuel (including liquid oxygen or cryogenic propellant) remaining in the booster delivery unit in one or more rocket bodies at the time of shutdown, resulting in a reduction in the actual fuel consumption, and thus increasing the dead weight of the rocket, limiting the further improvement of the rocket's carrying capacity. Further research has found that the cause of this problem is that in the multiple booster delivery units, the liquid level drop speeds in the multiple liquid oxygen tanks 1 are inconsistent, and the liquid level drop speeds in the multiple cryogenic propellant tanks 2 are also inconsistent. When the fuel in a tank (including the liquid oxygen tank 1 and the cryogenic propellant tank 2) is exhausted and needs to be shut down, there is still unconsumed fuel in the remaining tanks.

[0025] In order to solve this problem, in an embodiment of the present invention, the liquid parts of multiple cryogenic propellant tanks 2 on the bundled rocket are connected together, and the liquid part of the liquid oxygen tank 1 is also connected together, so that the liquid level in each tank can always be kept consistent when the fuel is transported to the engine, so that the fuel in all tanks can be exhausted when the engine is shut down, thereby reducing the remaining fuel, and further reducing the dead weight of the rocket, thereby improving the carrying capacity of the rocket.

[0026] Furthermore, the gas phase spaces of the liquid oxygen tank 1 are interconnected through the liquid oxygen tank cross-pressurization pipeline 20 , and the gas phase spaces of the cryogenic propellant tank 2 are interconnected through the propellant tank cross-pressurization pipeline 22 .

[0027] After cross-connecting the liquid oxygen and cryogenic propellant in different tanks, it is also necessary to connect the gas phase space of each tank to ensure that the air pillow pressure of each tank is the same, which is also an important condition to ensure that the liquid level can drop synchronously.

[0028] Furthermore, the pressurized delivery unit also includes an engine 3; the liquid oxygen tank 1 is arranged above the cryogenic propellant tank 2; the liquid oxygen tank 1 is connected to the engine 3 through a liquid oxygen delivery main line 16, and the cryogenic propellant tank 2 is connected to the engine 3 through a propellant delivery main line; a propellant self-generated supercharger 9 and an oxygen self-generated supercharger 4 are arranged on the engine 3, a propellant tank energy absorber 11 is arranged on the top of the inner side of the cryogenic propellant tank 2, and a liquid oxygen tank energy absorber 7 is arranged on the top of the inner side of the liquid oxygen tank 1, the propellant self-generated supercharger 9 and the propellant tank energy absorber 11 are connected through a propellant self-boosting pipeline 10, and the oxygen self-generated supercharger 4 and the liquid oxygen tank energy absorber 7 are connected through an oxygen self-boosting pipeline 5.

[0029] The structure of each booster delivery unit is as follows Figure 1As shown, it is basically the same as the prior art. In the embodiment of the present invention, a tunnel pipe type transportation scheme is still adopted, that is, a liquid oxygen transportation main line 16 is set at the bottom of the upper liquid oxygen tank 1, and then the liquid oxygen transportation main line 16 passes through the propellant tank tunnel pipe 17 opened in the middle of the lower cryogenic propellant tank 2, and finally the propellant is transported to the engine 3 (the connection method between the liquid oxygen tank 1 and the engine is the same as the prior art, and is not shown in the figure). At the same time, in the embodiment of the present invention, both the liquid oxygen tank 1 and the cryogenic propellant tank 2 adopt an open self-pressurization method to provide the air pillow pressure.

[0030] Furthermore, the oxygen self-pressurization pipeline 5 is connected to the liquid oxygen tank cross-pressurization pipeline 20; a liquid oxygen tank bottom interface 14 is provided at the bottom of the liquid oxygen tank 1, and the liquid oxygen tank bottom interface 14 is connected to the liquid oxygen tank cross-transport pipeline 21; a propellant tank top interface 12 is provided at the top of the cryogenic propellant tank 2, and a propellant tank bottom interface 15 is provided at the bottom of the cryogenic propellant tank 2, the propellant tank top interface 12 is connected to the propellant tank cross-pressurization pipeline 22, and the propellant tank bottom interface 15 is connected to the propellant tank cross-transport pipeline 23.

[0031] In order to realize cross-pressurization transportation, a propellant tank top interface 12 is opened at the top of the cryogenic propellant tank 2, and a propellant tank bottom interface 15 is set at the bottom of the cryogenic propellant tank 2, which are respectively used to realize the connection of the air pillow pressure and the connection of the liquid level between each cryogenic propellant tank 2; a liquid oxygen tank bottom interface 14 is set at the bottom of the liquid oxygen tank 1 to realize the liquid level connection between each liquid oxygen tank 1; and no additional interface is required at the top of the liquid oxygen tank 1, and a first tee 6 can be directly set on the oxygen self-pressurization pipeline 5 before entering the liquid oxygen tank 1, and multiple first tees 6 are connected together through the liquid oxygen tank cross-pressurization pipeline 20 to ensure that the air pillow pressure between each liquid oxygen tank 1 is the same.

[0032] Furthermore, the cryogenic propellant cross-pressurization delivery system further includes a propellant tank safety valve 13 , and the propellant tank safety valve 13 is disposed in the propellant tank cross-pressurization pipeline 22 .

[0033] In the prior art, the propellant tank safety valve 13 is arranged at the top of the cryogenic propellant tank 2 and is connected to the cryogenic propellant tank 2 to directly obtain the air pillow pressure of the cryogenic propellant tank 2; in the embodiment of the present invention, since the gas phase space (i.e., the air pillow part) of multiple cryogenic propellant tanks 2 has been cross-connected through the propellant tank cross-pressurization pipeline 22, it is only necessary to set one propellant tank safety valve 13 on the propellant tank cross-pressurization pipeline 22, so as to provide overpressure protection for three cross-connected cryogenic propellant tanks 2 at the same time, and reduce the number of propellant tank safety valves 13 configured, thereby reducing the cost.

[0034] Furthermore, the cryogenic propellant cross-pressurization delivery system further includes a liquid oxygen tank safety valve 8 , which is disposed in the liquid oxygen tank cross-pressurization pipeline 20 .

[0035] Correspondingly, only one liquid oxygen tank safety valve 8 needs to be provided on the liquid oxygen tank cross-pressurization pipeline 20 to provide overpressure protection for the three cross-connected liquid oxygen tanks 1 .

[0036] Furthermore, the cryogenic propellant cross-pressurization delivery system also includes a liquid oxygen delivery multi-port 18; each set of pressurization delivery units includes multiple engines 3; the liquid oxygen delivery multi-port 18 includes a top connection port and multiple side connection ports, the top connection port is connected to the liquid oxygen delivery main line 16, and the side connection port is connected to the engine 3 through a liquid oxygen branch delivery pipe 19; the number of side connection ports is the same as the number of engines 3 in each set of pressurization delivery units.

[0037] The booster delivery unit is usually provided with a plurality of engines 3 connected in parallel. Therefore, the liquid oxygen delivery multi-channel 18 can be provided to better evenly distribute the liquid oxygen delivered by the liquid oxygen delivery main line 16 to each engine 3. The structure of the liquid oxygen delivery multi-channel 18 is as follows: Figure 3 shown.

[0038] Furthermore, usually, there are eight, nine, or even more engines 3 in each set of boosting and delivery units. In the embodiment of the present invention, the most common configuration of 8 engines is preferably adopted; at this time, the 8 engines 3 require 8 side connection ports, plus a top connection port for connecting to the liquid oxygen delivery main line 16, so the liquid oxygen delivery multi-port 18 at this time has nine ports.

[0039] Furthermore, in actual application, the preferred method is that the first-stage rocket assembly consists of a core first-stage body and two booster first-stage bodies on both sides, and each body is provided with a set of booster delivery units, so there are three sets of booster delivery units in each first-stage assembly.

[0040] like Figure 2 As shown, an embodiment of the present invention further provides a parallel rocket, wherein the first-stage assembly of the parallel rocket is provided with the cryogenic propellant cross-pressurization and delivery system as described above; the first-stage assembly of the parallel rocket includes a core first-stage rocket body 100, and two booster first-stage rocket bodies 200 arranged on the sides of the core first-stage rocket body; a set of pressurization and delivery units are respectively provided on the core first-stage rocket body 100 and each booster first-stage rocket body 200.

[0041] The cryogenic propellant cross-pressurization and delivery system of the embodiment of the present invention is mainly used in the first-stage assembly of the rocket. The first-stage assembly is the aforementioned bundled structure, including the core first-stage rocket body 100 in the middle, and two booster first-stage rocket bodies 200 bundled on both sides. Each rocket body is provided with a set of pressurization and delivery units. This configuration form has been widely used. Different from the prior art, in the example of the present invention, the pressurization and delivery units in each rocket body are cross-connected, thereby ensuring that the liquid levels in the cryogenic propellant tank 2 and the liquid oxygen tank 1 can drop synchronously, ensuring that the fuel in each tank is consumed at the same time when the first-stage assembly is shut down, thereby reducing the safety margin of the remaining fuel, reducing the dead weight of the rocket, and improving the carrying capacity of the rocket.

[0042] The working process of the cryogenic propellant cross-pressurization delivery system and the parallel rocket is described in detail below with a specific embodiment:

[0043] 1) During the flight phase of the first stage of the rocket assembly, the liquid oxygen tank 1 adopts a self-pressurization scheme, and the oxygen self-pressurizer 4 heats the liquid oxygen into high-temperature oxygen, and then the high-temperature oxygen is pressurized on the rocket to the liquid oxygen tank 1 through the oxygen self-pressurization pipeline 5, the first three-way 6, and the liquid oxygen tank energy dissipator 7. In this process, the pressurization method of the liquid oxygen tank 1 is open pressurization, and the control system is not used for closed feedback.

[0044] 2) At the same time, the cryogenic propellant tank 2 adopts a self-pressurizing scheme, and the propellant self-pressurizing device 9 gasifies the cryogenic propellant, and the propellant gas is pressurized on the arrow to the cryogenic propellant tank 2 through the propellant self-pressurizing pipeline 10 and the propellant tank energy dissipator 11. In this process, the pressurization method of the cryogenic propellant tank 2 is open pressurization, and the control system is not used for closed feedback.

[0045] 3) During the flight of the first stage assembly of the rocket, when the air pillow pressure of the liquid oxygen tank 1 is higher than the opening pressure of the liquid oxygen tank safety valve 8, the liquid oxygen tank safety valve 8 is opened; when the air pillow pressure of the liquid oxygen tank 1 is lower than the closing pressure of the liquid oxygen tank safety valve 8, the liquid oxygen tank safety valve 8 is closed. When the boost flow rate of the liquid oxygen tank 1 is too large, the liquid oxygen tank safety valve 8 will be opened, and the liquid oxygen tank safety valve 8 will be used to control the air pillow pressure of the liquid oxygen tank 1.

[0046] 4) During the first stage flight of the rocket first stage assembly, when the air cushion pressure of the cryogenic propellant tank 2 is higher than the opening pressure of the propellant tank safety valve 13, the propellant tank safety valve 13 is opened, and when the air cushion pressure of the cryogenic propellant tank 2 is lower than the closing pressure of the propellant tank safety valve 13, the low propellant tank safety valve 13 is closed. If the boost flow of the cryogenic propellant tank 2 is too large, causing the propellant tank safety valve 13 to open, the propellant tank safety valve 13 is used to control the air cushion pressure of the cryogenic propellant tank 2.

[0047] 5) The liquid oxygen in the liquid oxygen tank 1 is transported to the liquid oxygen pump inlet 28 of the engine 3 through the rear bottom of the oxygen tank, the liquid oxygen delivery main line 16, the liquid oxygen delivery multi-way 18, and the liquid oxygen branch delivery pipe 19.

[0048] 6) To increase the thrust of the first stage assembly and improve the rocket's carrying capacity, such as Figure 2 As shown, the core first-stage rocket body 100 is duplicated into two booster first-stage rocket bodies 200 (or referred to as booster first-stage rocket body A and booster first-stage rocket body B), and the core first-stage rocket body 100, the booster first-stage rocket body A and the booster first-stage rocket body B are bundled together.

[0049] 7) To realize the cross-pressurization of the liquid oxygen tank 1 on the first-stage assembly, Figure 2 As shown, the first tee 6 on the core first stage body 100, the first tee 6 on the booster first stage body A, and the first tee 6 on the booster first stage body B are connected to each other through the liquid oxygen tank cross-pressurization pipeline 20 and the second tee 24, so that the three liquid oxygen tanks 1 on the first stage assembly are connected to each other, ensuring that the air pillow pressures of the three liquid oxygen tanks 1 remain uniform, thereby realizing cross-pressurization of the liquid oxygen tanks 1. At the same time, a liquid oxygen tank safety valve 8 is set on the liquid oxygen tank cross-pressurization pipeline 20 to realize the air pillow pressure control of the liquid oxygen tank 1 of the first stage assembly.

[0050] The cross-pressurization of the liquid oxygen tank 1 on the first-stage assembly is achieved, which can ensure that the air pillow pressures of the three liquid oxygen tanks 1 remain consistent, and the pressure control of the liquid oxygen tank 1 can be achieved with only one liquid oxygen tank safety valve 8. Compared with the traditional method of using one liquid oxygen tank safety valve 8 for each liquid oxygen tank 1, this system saves two liquid oxygen tank safety valves 8.

[0051] 8) In order to realize the cross-conveying of the liquid oxygen tanks 1 on the first-stage assembly, the liquid oxygen tank bottom interface 14 of the core first-stage rocket body 100, the liquid oxygen tank bottom interface 14 on the booster first-stage rocket body A, and the liquid oxygen tank bottom interface 14 on the booster first-stage rocket body B are respectively connected to each other by the liquid oxygen tank cross-conveying pipeline 21 and the third tee 25, so that the liquid parts of the three liquid oxygen tanks 1 on the first-stage assembly are connected to each other, ensuring that the liquid oxygen levels of the three liquid oxygen tanks 1 are consistent and the liquid oxygen in the three liquid oxygen tanks 1 is consumed at the same time, thereby realizing the cross-conveying of the liquid oxygen tanks 1.

[0052] Through the cross-transportation of the three liquid oxygen tanks 1 on the first-stage assembly, the pressure at the rear bottom of the three liquid oxygen tanks 1 can be kept consistent, thereby ensuring that the liquid oxygen levels of the three liquid oxygen tanks 1 are consistent, and the liquid oxygen in the three liquid oxygen tanks 1 can be consumed at the same time. In the prior art, each liquid oxygen tank flows out independently. Due to the differences in turbo pump speed, boost pressure, engine thrust, mixing ratio, and failure of a single engine 3, the liquid oxygen levels of the three liquid oxygen tanks 1 are inconsistent at the time of shutdown. Taking the minimum liquid level as the system design requirement will result in a larger residual liquid oxygen safety margin in the three liquid oxygen tanks 1. By achieving a uniform liquid oxygen level, the system can reduce the residual liquid oxygen safety margin, reduce the dead weight of the rocket, and improve the carrying capacity of the rocket.

[0053] 9) The cross-pressurization of the liquid oxygen tank 1 of the first-stage assembly realizes the uniformity of the air pillow pressure of the liquid oxygen tank 1, and provides the necessary conditions for the cross-transportation of the liquid oxygen tank 1 to achieve the uniformity of the liquid oxygen level.

[0054] 10) To realize cross-pressurization of the cryogenic propellant tank 2 on the first-stage assembly, the top interface 12 of the propellant tank on the core first-stage body 100, the top interface 12 of the propellant tank on the booster first-stage body A, and the top interface 12 of the propellant tank on the booster first-stage body B are connected to each other through the propellant tank cross-pressurization pipeline 22 and the fourth three-way 26, so that the cryogenic propellant tank 2 of the core first-stage body 100, the cryogenic propellant tank 2 of the booster first-stage body A, and the cryogenic propellant tank 2 of the booster first-stage body B are connected to each other, ensuring that the air pillow pressure of the three cryogenic propellant tanks 2 remains uniform, and realizing cross-pressurization of the three cryogenic propellant tanks 2. A propellant tank safety valve 13 is set on the propellant tank cross-pressurization pipeline 22 to realize the control of the air pillow pressure of the three cryogenic propellant tanks 2.

[0055] Through the cross-pressurization of the cryogenic propellant tank 2 of the first-stage assembly, the air pillow pressure of the three cryogenic propellant tanks 2 can be ensured to be consistent, and the pressure control of the cryogenic propellant tank 2 can be achieved with only one propellant tank safety valve 13. Compared with the traditional method of using one propellant tank safety valve 13 for each cryogenic propellant tank 2, this system saves two propellant tank safety valves 13.

[0056] 11) To realize the cross-transportation of the first-stage cryogenic propellant tank 2, the propellant tank bottom interface 15 on the core first-stage body 100, the propellant tank bottom interface 15 on the booster first-stage body A, and the cryogenic booster propellant tank bottom interface 15 on the first-stage body B are interconnected by using the propellant tank cross-transportation pipeline 23 and the fifth three-way 27, so that the liquid parts of the three cryogenic propellant tanks 2 on the first-stage assembly are connected to each other, ensuring that the liquid propellant levels in the three cryogenic propellant tanks 2 are consistent and the liquid propellants in the three cryogenic propellant tanks 2 are consumed at the same time, thereby realizing the cross-transportation of the cryogenic propellant tanks 2 of the first-stage assembly.

[0057] The cross-transportation of the cryogenic propellant tanks 2 of the first-stage assembly can ensure that the pressure at the rear bottom of the three cryogenic propellant tanks 2 is consistent, thereby ensuring that the cryogenic propellant liquid levels of the three cryogenic propellant tanks 2 are consistent, and the cryogenic propellants of the three cryogenic propellant tanks 2 can be consumed at the same time. In the traditional technology, each cryogenic propellant tank 2 is discharged independently. Due to the differences in turbo pump speed, boost pressure, engine thrust, and mixing ratio, the failure of a single engine 3 will cause the cryogenic propellant liquid levels of the three cryogenic propellant tanks 2 to be inconsistent when shutting down. Taking the minimum liquid level as the system design requirement will result in a larger safety margin of the remaining propellant in the three cryogenic propellant tanks 2. By achieving the uniformity of the cryogenic propellant liquid level, the system can reduce the safety margin of the remaining propellant, reduce the dead weight of the rocket, and improve the carrying capacity of the rocket.

[0058] 12) The cross-pressurization of the cryogenic propellant tank 2 of the first-stage assembly realizes the uniformity of the air cushion pressure of the cryogenic propellant tank 2, and provides the necessary conditions for the cross-transportation of the cryogenic propellant tank 2 to achieve the uniformity of the cryogenic propellant liquid level.

[0059] 13) In addition, if a failure occurs in an engine 3 on the core first stage rocket body 100 or a booster first stage rocket body 200, the remaining propellant in the tank can be transported to the tanks of other rocket bodies (including the liquid oxygen tank 1 or the cryogenic propellant tank 2), thereby achieving full utilization of the fuel.

[0060] In addition, in the above specific embodiment, the method of pressurizing the first-stage assembly on the rocket during the flight phase after the rocket is ignited is:

[0061] 1) The safety valve is a pressure release safety device for the tank (including the liquid oxygen tank 1 or the cryogenic propellant tank 2), which can be opened and closed according to a predetermined pressure. The safety valve is used to protect the rocket tank from overpressure and is a key valve to ensure the pressure safety of the tank. During the flight, when the tank pressure exceeds the specified value, the safety valve automatically opens to discharge excess gas; when the tank exhaust pressure drops to the specified value, the safety valve can be automatically closed and remain sealed. In the embodiment of the present invention, the safety valve (including the liquid oxygen tank safety valve 8 and the propellant tank safety valve 13) is a mechanical structure without a control system.

[0062] 2) In the embodiment of the present invention, both the liquid oxygen tank 1 and the cryogenic propellant tank 2 are open self-pressurization schemes, without the participation of a control system, and the pressurization scheme is simple and reliable. Through simulation calculations, it can be determined that during the flight of the first-stage assembly of the rocket, the liquid oxygen tank safety valve 8 and the propellant tank safety valve 13 in the embodiment of the present invention are opened 4 to 5 times, which is significantly lower than the average level of the prior art. Therefore, it can meet the life requirements of the safety valve and prevent the problem of insufficient boost pressure caused by calculation deviation.

[0063] 3) The liquid oxygen tank 1 uses the liquid oxygen tank safety valve 8 to control the air pillow pressure of the liquid oxygen tank, and the air pillow pressure of the liquid oxygen tank 1 is controlled by opening and closing the liquid oxygen tank safety valve 8; the cryogenic propellant tank 2 uses the propellant tank safety valve 13 to control the air pillow pressure of the cryogenic propellant tank 2, and the air pillow pressure of the cryogenic propellant tank 2 is controlled by opening and closing the propellant tank safety valve 13.

[0064] In the above specific embodiment, the air pillow pressure and other pressure distributions of the liquid oxygen tank 1 are as shown in the attached figure. Figure 4 As shown, where P Ybxfkq is the opening pressure of oxygen tank safety valve 16, P Ybxfgb is the closing pressure of the liquid oxygen tank safety valve, P Ybxfqm is the airtight pressure of the liquid oxygen tank safety valve, P Y0 is the actual boost pressure of liquid oxygen tank 1, P Ymin It is the minimum air cushion pressure of liquid oxygen tank 1 required by rocket engine 3.

[0065] In the above specific embodiment, the air pillow pressure and other pressure distributions of the cryogenic propellant tank 2 are as shown in the attached figure. Figure 5 As shown, where P R0 is the actual boost pressure of the cryogenic propellant tank 2, P Rmin is the minimum cushion pressure of cryogenic propellant tank 2 required by engine 3, P Rbxfkq is the opening pressure of the propellant tank safety valve, P Rbxfgb is the closing pressure of the propellant tank safety valve, P Rbxfqm It is the airtight pressure of the propellant tank safety valve.

[0066] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0067] The disclosed embodiments are described above to enable any person skilled in the art to implement or use the present invention. Various modifications of these embodiments are obvious to those skilled in the art, and the general principles defined herein may also be applied to other embodiments without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments given herein, but is consistent with the broadest scope of the principles and novel features disclosed in this application.

[0068] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A cryogenic propellant cross-pressurization and delivery system, comprising a plurality of pressurization and delivery units, each of which comprises a liquid oxygen tank (1) and a cryogenic propellant tank (2), characterized in that: The liquid phase spaces of the liquid oxygen tank (1) are interconnected via a liquid oxygen tank cross-transfer pipeline (21), and the liquid phase spaces of the cryogenic propellant tank (2) are interconnected via a propellant tank cross-transfer pipeline (23); The cryogenic propellant cross-pressurization and delivery system is applied to the first-stage assembly of a rocket. The first-stage assembly of a rocket consists of a core first-stage rocket body and two booster first-stage rocket bodies on both sides. A set of the pressurization and delivery unit is arranged in each rocket body. The cryogenic propellant cross-pressurization delivery system further comprises a propellant tank safety valve (13), wherein the propellant tank safety valve (13) is arranged in the propellant tank cross-pressurization pipeline (22); The cryogenic propellant cross-pressurization delivery system further comprises a liquid oxygen tank safety valve (8), wherein the liquid oxygen tank safety valve (8) is arranged in the liquid oxygen tank cross-pressurization pipeline (20).

2. The cryogenic propellant cross-pressurization delivery system according to claim 1, characterized in that: The gas phase spaces of the liquid oxygen tank (1) are interconnected via a liquid oxygen tank cross-pressurization pipeline (20), and the gas phase spaces of the cryogenic propellant tank (2) are interconnected via a propellant tank cross-pressurization pipeline (22).

3. The cryogenic propellant cross-pressurization delivery system according to claim 2, characterized in that: The pressurized delivery unit further comprises an engine (3); the liquid oxygen tank (1) is arranged above the cryogenic propellant tank (2); the liquid oxygen tank (1) is connected to the engine (3) via a liquid oxygen delivery main line (16), and the cryogenic propellant tank (2) is connected to the engine (3) via a propellant delivery main line; a propellant autogenous supercharger (9) and an oxygen autogenous supercharger (4) are arranged on the engine (3); a propellant tank energy dissipator (11) is arranged on the top of the inner side of the cryogenic propellant tank (2), and a liquid oxygen tank energy dissipator (7) is arranged on the top of the inner side of the liquid oxygen tank (1); the propellant autogenous supercharger (9) and the propellant tank energy dissipator (11) are connected via a propellant autogenous pressurization line (10), and the oxygen autogenous supercharger (4) and the liquid oxygen tank energy dissipator (7) are connected via an oxygen autogenous pressurization line (5).

4. The cryogenic propellant cross-pressurization delivery system according to claim 3, characterized in that: The oxygen self-pressurizing pipeline (5) is in communication with the liquid oxygen tank cross-pressurizing pipeline (20); a liquid oxygen tank bottom interface (14) is provided at the bottom of the liquid oxygen tank (1), and the liquid oxygen tank bottom interface (14) is in communication with the liquid oxygen tank cross-transport pipeline (21); a propellant tank top interface (12) is provided at the top of the cryogenic propellant tank (2), and a propellant tank bottom interface (15) is provided at the bottom of the cryogenic propellant tank (2), the propellant tank top interface (12) is in communication with the propellant tank cross-pressurizing pipeline (22), and the propellant tank bottom interface (15) is in communication with the propellant tank cross-transport pipeline (23).

5. The cryogenic propellant cross-pressurization delivery system according to claim 3, characterized in that: It also includes a liquid oxygen delivery multi-way (18); each set of the boost delivery unit includes a plurality of the engines (3); the liquid oxygen delivery multi-way (18) includes a top connection port and a plurality of side connection ports, the top connection port is connected to the liquid oxygen delivery main line (16), and the side connection port is connected to the engine (3) through a liquid oxygen branch delivery pipe (19); the number of the side connection ports is the same as the number of the engines (3) in each set of the boost delivery system.

6. The cryogenic propellant cross-pressurization delivery system according to claim 5, characterized in that: Each of the boosting and conveying units comprises eight engines (3), and the liquid oxygen conveying multi-port (18) has nine ports.

7. The cryogenic propellant cross-pressurization delivery system according to claim 2, characterized in that: There are three sets of booster delivery units.

8. A parallel rocket, characterized in that: The first stage assembly of the parallel rocket is provided with a cryogenic propellant cross-pressurization and delivery system as described in any one of claims 1 to 7; the first stage assembly of the parallel rocket comprises a core first stage body (100) and two booster first stage bodies (200) arranged on the sides of the core first stage body; the core first stage body (100) and each of the booster first stage bodies (200) are respectively provided with a set of pressurization and delivery units.

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