Two-stage deep subcooled liquid oxygen high flow filling system

Abstract

The application relates to a low-temperature propellant filling system, in particular to a two-stage deep supercooled liquid oxygen large-flow filling system, which comprises a conventional liquid oxygen storage device, a first-stage liquid oxygen supercooler, a second-stage liquid oxygen supercooler, a supercooled liquid oxygen storage device, a liquid oxygen filling main pipeline, a first-stage liquid oxygen filling branch pipeline, a first-stage liquid oxygen output branch pipeline, a second-stage liquid oxygen filling branch pipeline and a second-stage liquid oxygen output branch pipeline, wherein the supercooled liquid oxygen storage device is provided with a liquid oxygen mixing device; the first-stage liquid oxygen supercooler is used for cooling liquid oxygen in the conventional liquid oxygen storage device into supercooled liquid oxygen; the second-stage liquid oxygen supercooler is used for cooling the supercooled liquid oxygen into deep supercooled liquid oxygen; and the connection points of the first-stage liquid oxygen filling branch pipeline, the first-stage liquid oxygen output branch pipeline, the second-stage liquid oxygen filling branch pipeline, the second-stage liquid oxygen output branch pipeline and the liquid oxygen filling main pipeline are sequentially arranged from upstream to downstream along the liquid oxygen filling main pipeline. The application can realize deep supercooled liquid oxygen large-flow filling and avoid temperature stratification.

Description

TECHNICAL FIELD

[0001] The application relates to a low-temperature propellant filling system, in particular to a two-stage deep supercooled liquid oxygen large-flow filling system. BACKGROUND

[0002] Low-temperature propellants (such as liquid hydrogen, liquid oxygen, methane, etc.) have the characteristics of high specific impulse, non-toxic and non-polluting, and relatively low price, and are widely used in spacecraft, and liquid oxygen is one of the most widely used.

[0003] The quality of liquid oxygen is mainly reflected in purity and temperature. The temperature of liquid oxygen is crucial for the start of the liquid oxygen centrifugal pump of the ground filling system and the liquid oxygen turbine pump on the rocket. At the same time, the density of liquid oxygen is closely related to the temperature. When the liquid oxygen is supercooled from 90K to 67K, the mass of the liquid oxygen per unit volume increases by 8%~10%, and in the case of filling the propellant with the same mass, the structure weight of the rocket filled with supercooled propellant is 15%~25% lighter than that of the rocket filled with propellant in the normal pressure state, and the cost of the rocket is reduced by more than 11%. When supercooled liquid oxygen is used in the launch site filling system, it can effectively prevent two-phase flow in the conveying pipeline and shorten the pre-cooling time of the conveying pipeline and equipment in the filling process. At the same time, supercooled liquid oxygen has obvious effect on improving the rocket payload coefficient. However, the existing supercooled liquid oxygen filling system cannot meet the use requirements of the supercooling degree of liquid oxygen, the supercooling filling speed and the total mass during filling. In order to improve the rocket payload coefficient and the working stability, the domestic low-temperature rocket has an urgent need for deep supercooled liquid oxygen large-flow filling. SUMMARY

[0004] The technical problem to be solved by the application is to provide a two-stage deep supercooled liquid oxygen large-flow filling system which can realize deep supercooled liquid oxygen large-flow filling and avoid temperature stratification of deep supercooled liquid oxygen.

[0005] In order to solve the above technical problems, the application provides the following technical scheme:

[0006] The two-stage deep supercooled liquid oxygen large-flow filling system comprises a conventional liquid oxygen storage device, a first-stage liquid oxygen supercooler, a second-stage liquid oxygen supercooler, a supercooled liquid oxygen storage device, a liquid oxygen filling main pipeline, a first-stage liquid oxygen filling branch pipeline, a first-stage liquid oxygen output branch pipeline, a second-stage liquid oxygen filling branch pipeline, and a second-stage liquid oxygen output branch pipeline.

[0007] Further, the system further comprises a liquid oxygen pump, a liquid oxygen pump inlet branch pipeline, and a liquid oxygen pump outlet branch pipeline, wherein the inlet end of the liquid oxygen pump is connected to the liquid oxygen filling main pipeline through the liquid oxygen pump inlet branch pipeline, the outlet end of the liquid oxygen pump is connected to the liquid oxygen filling main pipeline through the liquid oxygen pump outlet branch pipeline, the liquid oxygen pump inlet branch pipeline is provided with a first oxygen filling switch valve, the connection point of the liquid oxygen pump inlet branch pipeline and the liquid oxygen filling main pipeline is a fifth connection point, the connection point of the liquid oxygen pump outlet branch pipeline and the liquid oxygen filling main pipeline is a sixth connection point, and the fifth connection point and the sixth connection point are both located between the conventional liquid oxygen storage device and the first connection point.

[0008] Further, the third oxygen filling switch valve, the fourth oxygen filling switch valve and the fifth oxygen filling switch valve are respectively arranged between the first connection point and the second connection point, between the third connection point and the fourth connection point, and between the sixth connection point and the first connection point on the liquid oxygen filling main pipeline.

[0009] Further, the liquid oxygen filling circulation pipeline is connected between the conventional liquid oxygen storage device and the liquid oxygen filling main pipeline, and a connection point of the liquid oxygen filling circulation pipeline and the liquid oxygen filling main pipeline is located between the fourth connection point and the sixth oxygen filling switch valve.

[0010] Further, the primary liquid oxygen subcooler and the secondary liquid oxygen subcooler are both plate-fin heat exchangers, the primary liquid oxygen subcooler uses low-temperature liquid nitrogen as a refrigerant medium, and the secondary liquid oxygen subcooler uses ultralow-temperature liquid nitrogen as a refrigerant medium.

[0011] Further, it also comprises a liquid nitrogen storage device, a liquid nitrogen buffer device, a first liquid nitrogen filling branch pipe, a first nitrogen gas output branch pipe, a second liquid nitrogen filling branch pipe, a second nitrogen gas output branch pipe, the first liquid oxygen super-cooler is provided with a first refrigerant inlet and a first refrigerant outlet, the second liquid oxygen super-cooler is provided with a second refrigerant inlet and a second refrigerant outlet, the liquid nitrogen storage device is connected to the first refrigerant inlet through the first liquid nitrogen filling branch pipe, the first liquid nitrogen output branch pipe is connected to the first refrigerant outlet, the liquid nitrogen in the liquid nitrogen storage device enters the first liquid oxygen super-cooler as a refrigerant medium through the first liquid nitrogen filling branch pipe and the first refrigerant inlet, exchanges heat with the liquid oxygen in the first liquid oxygen super-cooler, and the liquid oxygen is cooled to super-cooled liquid oxygen after heat exchange, the liquid nitrogen is warmed to form nitrogen gas, and the nitrogen gas formed after warming is discharged through the first refrigerant outlet and the first nitrogen gas output branch pipe, the liquid nitrogen buffer device is connected to a first vacuumizing device, the first vacuumizing device vacuums the liquid nitrogen buffer device, the liquid nitrogen storage device is connected to the inlet of the liquid nitrogen buffer device through a connecting pipe, the outlet of the liquid nitrogen buffer device is connected to the second refrigerant inlet through the second liquid nitrogen filling branch pipe, the second nitrogen gas output branch pipe is connected to the second refrigerant outlet, the liquid nitrogen in the liquid nitrogen storage device enters the liquid nitrogen buffer device, the liquid nitrogen absorbs its own heat to form super-cooled liquid nitrogen in the liquid nitrogen buffer device, the super-cooled liquid nitrogen enters the second liquid oxygen super-cooler as a refrigerant medium through the second liquid nitrogen filling branch pipe and the second refrigerant inlet, exchanges heat with the super-cooled liquid oxygen in the second liquid oxygen super-cooler, and the super-cooled liquid oxygen is cooled to deep super-cooled liquid oxygen after heat exchange, the super-cooled liquid nitrogen is warmed, and the nitrogen gas after warming is discharged through the second refrigerant outlet and the second nitrogen gas output branch pipe, and one switch valve is arranged on each of the first liquid nitrogen filling branch pipe, the first nitrogen gas output branch pipe, the second liquid nitrogen filling branch pipe and the second nitrogen gas output branch pipe.

[0012] Further, it also comprises a second vacuumizing device, the output end of the second nitrogen gas output branch pipe is connected to the second vacuumizing device, and the second vacuumizing device vacuums the cavity of the second liquid oxygen super-cooler to a target vacuum degree.

[0013] Further, the first vacuumizing device and the second vacuumizing device are two vacuum pumps connected in parallel, and the vacuum pumps are connected to the cavity of the liquid nitrogen buffer device through a second nitrogen gas output branch pipe extension pipe to vacuumize the liquid nitrogen buffer device.

[0014] Further, a nitrogen exhaust tower and a plurality of heat exchangers in parallel are further included, the output end of the secondary nitrogen output branch pipe is connected to the input end of each heat exchanger, the output end of each heat exchanger is connected to the input end of the vacuum pump, a flow regulating valve is arranged between the output end of the secondary nitrogen output branch pipe and each heat exchanger, and the output end of the vacuum pump and the primary nitrogen output branch pipe are connected to the nitrogen exhaust tower.

[0015] Further, temperature sensors, pressure sensors and flow meters are arranged on the primary liquid nitrogen filling branch pipe and the secondary liquid nitrogen filling branch pipe, respectively, and flow regulating valves are further arranged on the primary liquid nitrogen filling branch pipe and the secondary liquid nitrogen filling branch pipe, respectively, temperature sensors, pressure sensors and flow meters are arranged on the liquid oxygen filling main pipeline between the fourth connecting point and the supercooled liquid oxygen storage device and between the conventional liquid oxygen storage device and the fifth connecting point, respectively.

[0016] Compared with the prior art, the two-stage deep supercooled liquid oxygen large-flow filling system has at least the following beneficial effects:

[0017] The two-stage deep supercooled liquid oxygen large-flow filling system includes a primary liquid oxygen supercooler and a secondary liquid oxygen supercooler, the connecting points of the primary liquid oxygen supercooler and the liquid oxygen filling main pipeline are the first connecting point and the second connecting point, the connecting points of the secondary liquid oxygen supercooler and the liquid oxygen filling main pipeline are the third connecting point and the fourth connecting point, and the first connecting point, the second connecting point, the third connecting point and the fourth connecting point are sequentially arranged along the liquid oxygen filling main pipeline from upstream to downstream, so that the primary liquid oxygen supercooler and the secondary liquid oxygen supercooler form a series mode, thereby enabling the liquid oxygen in the conventional liquid oxygen storage device to be continuously supercooled in two stages, improving the efficiency of liquid oxygen supercooling, having the ability to directly produce 66K deep supercooled liquid oxygen, enabling liquid oxygen to be deeply supercooled under the condition of large flow, ensuring that the deeply supercooled liquid oxygen can be filled into the aircraft in large flow, and simultaneously, the liquid oxygen mixing device arranged in the supercooled liquid oxygen storage device can avoid temperature stratification of liquid oxygen, the liquid nitrogen buffer device can stably provide liquid nitrogen during large-flow supercooling, and the load of the vacuum pump is reduced.

[0018] The two-stage deep supercooled liquid oxygen large-flow filling system will be further described below with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 FIG. 1 is a structural schematic diagram of the two-stage deep supercooled liquid oxygen large-flow filling system. DETAILED DESCRIPTION

[0020] As Figure 1The application is a two-stage supercooled liquid oxygen large-flow filling system, which comprises a conventional liquid oxygen storage device 01, a first-stage liquid oxygen supercooler 02, a second-stage liquid oxygen supercooler 03, a supercooled liquid oxygen storage device 04, a liquid oxygen filling main pipeline 51, a first-stage liquid oxygen filling branch pipeline 21, a first-stage liquid oxygen output branch pipeline 22, a second-stage liquid oxygen filling branch pipeline 31, and a second-stage liquid oxygen output branch pipeline 32. The supercooled liquid oxygen storage device 04 is provided with a liquid oxygen mixing device. The liquid oxygen filling main pipeline 51 is connected between the conventional liquid oxygen storage device 01 and the supercooled liquid oxygen storage device 04. The first-stage liquid oxygen supercooler 02 is used to cool the liquid oxygen in the conventional liquid oxygen storage device 01 to supercooled liquid oxygen. The second-stage liquid oxygen supercooler 03 is used to cool the supercooled liquid oxygen to deeply supercooled liquid oxygen. The first-stage liquid oxygen filling branch pipeline 21, the first-stage liquid oxygen output branch pipeline 22, the second-stage liquid oxygen filling branch pipeline 31, and the second-stage liquid oxygen output branch pipeline 32 are respectively provided with a first-stage filling on-off valve 23, a first-stage output on-off valve 24, a second-stage filling on-off valve 33, and a second-stage output on-off valve 34. The first-stage liquid oxygen filling branch pipeline 21 is connected between the liquid oxygen filling main pipeline 51 and the liquid oxygen inlet of the first-stage liquid oxygen supercooler 02. The first-stage liquid oxygen output branch pipeline 22 is connected between the liquid oxygen outlet of the first-stage liquid oxygen supercooler 02 and the liquid oxygen filling main pipeline 51. The second-stage liquid oxygen filling branch pipeline 31 is connected between the liquid oxygen filling main pipeline 51 and the liquid oxygen inlet of the second-stage liquid oxygen supercooler 03. The second-stage liquid oxygen output branch pipeline 32 is connected between the liquid oxygen outlet of the second-stage liquid oxygen supercooler 03 and the liquid oxygen filling main pipeline 51. The first-stage liquid oxygen supercooler 02 and the second-stage liquid oxygen supercooler 03 are connected in series. The connection points of the first-stage liquid oxygen filling branch pipeline 21, the first-stage liquid oxygen output branch pipeline 22, the second-stage liquid oxygen filling branch pipeline 31, and the second-stage liquid oxygen output branch pipeline 32 and the liquid oxygen filling main pipeline 51 are respectively a first connection point, a second connection point, a third connection point, and a fourth connection point. The first connection point, the second connection point, the third connection point, and the fourth connection point are sequentially arranged along the liquid oxygen filling main pipeline 51 from upstream to downstream. The liquid oxygen at about 90K in the conventional liquid oxygen storage device 01 enters the first-stage liquid oxygen supercooler 02 through the first-stage liquid oxygen filling branch pipeline 21, is supercooled to supercooled liquid oxygen at about 80K in the first-stage liquid oxygen supercooler 02, is output to the liquid oxygen filling main pipeline 51 through the first-stage liquid oxygen output branch pipeline 22, enters the second-stage liquid oxygen supercooler 03 through the second-stage liquid oxygen filling branch pipeline 31, is supercooled to deeply supercooled liquid oxygen in the second-stage liquid oxygen supercooler 03, and is input to the supercooled liquid oxygen storage device 04 at about 66K. The liquid oxygen in the supercooled liquid oxygen storage device 04 is used as propellant to fill the spacecraft. The liquid oxygen mixing device in the supercooled liquid oxygen storage device 04 mixes the supercooled liquid oxygen and eliminates temperature stratification. Specifically, the liquid oxygen mixing device is a nozzle 41 arranged at the liquid oxygen inlet of the bottom cavity of the supercooled liquid oxygen storage device 04. The deeply supercooled liquid oxygen is sprayed into the supercooled liquid oxygen storage device 04 through the nozzle 41 to avoid temperature stratification.The two-stage deeply supercooled liquid oxygen large-flow filling system comprises a first-stage liquid oxygen supercooling device 02, a second-stage liquid oxygen supercooling device 03, a first connecting point and a second connecting point between the first-stage liquid oxygen supercooling device 02 and a liquid oxygen filling main pipeline 51, a third connecting point and a fourth connecting point between the second-stage liquid oxygen supercooling device 03 and the liquid oxygen filling main pipeline 51, and the first connecting point, the second connecting point, the third connecting point and the fourth connecting point are sequentially arranged from upstream to downstream along the liquid oxygen filling main pipeline 51, so that the first-stage liquid oxygen supercooling device 02 and the second-stage liquid oxygen supercooling device 03 form a series mode, liquid oxygen in a conventional liquid oxygen storage device 01 can be continuously supercooled in two stages, the efficiency of liquid oxygen supercooling is improved, the capacity of directly and continuously preparing 66K deeply supercooled liquid oxygen is achieved, liquid oxygen can be deeply supercooled under the condition of large flow, deeply supercooled liquid oxygen can be filled into a spacecraft in large flow, and a liquid oxygen mixing device arranged in a supercooled liquid oxygen storage device 04 can avoid temperature stratification of liquid oxygen.

[0021] Optionally, the two-stage deeply supercooled liquid oxygen large-flow filling system further comprises a liquid oxygen pump 11, a liquid oxygen pump inlet branch pipe 111 and a liquid oxygen pump outlet branch pipe 112, the inlet end of the liquid oxygen pump 11 is connected to the liquid oxygen filling main pipeline 51 through the liquid oxygen pump inlet branch pipe 111, the outlet end of the liquid oxygen pump 11 is connected to the liquid oxygen filling main pipeline 51 through the liquid oxygen pump outlet branch pipe 112, a first oxygen filling switch valve 113 is arranged on the liquid oxygen pump inlet branch pipe 111, the connecting point between the liquid oxygen pump inlet branch pipe 111 and the liquid oxygen filling main pipeline 51 is a fifth connecting point, the connecting point between the liquid oxygen pump outlet branch pipe 112 and the liquid oxygen filling main pipeline 51 is a sixth connecting point, the fifth connecting point and the sixth connecting point are both located between the conventional liquid oxygen storage device 01 and the first connecting point, and a second oxygen filling switch valve 114 is arranged on the liquid oxygen filling main pipeline 51 between the fifth connecting point and the sixth connecting point, so that the liquid oxygen pump 11 is connected in parallel to the liquid oxygen filling main pipeline 51, and pump filling or extrusion filling can be adopted when liquid oxygen is filled, the second oxygen filling switch valve 114 is closed and the first oxygen filling switch valve 113 is opened when pump filling is adopted, and the first oxygen filling switch valve 113 is closed and the second oxygen filling switch valve 114 is opened when extrusion filling is adopted. Two alternative methods can be adopted when liquid oxygen is filled, the reliability of the filling system is improved, the system can fully meet the needs of various filling conditions through equipment redundancy and filling pipeline redundancy, and the second-stage liquid oxygen supercooling device 03 and the supercooled liquid oxygen storage device 04 are connected to an external gas source, so that gas is supplied through the external gas source to maintain pressure when the internal cavity of the second-stage liquid oxygen supercooling device 03 or the supercooled liquid oxygen storage device 04 has a vacuum degree lower than a design value, and deformation and suction under negative pressure are prevented.

[0022] Optionally, the third oxygen filling switch valve 115, the fourth oxygen filling switch valve 116 and the fifth oxygen filling switch valve 117 are arranged on the liquid oxygen filling main pipeline 51 between the first connecting point and the second connecting point, between the third connecting point and the fourth connecting point, and between the sixth connecting point and the first connecting point, respectively, and the fifth oxygen filling switch valve 117 is a flow regulating valve. The fifth oxygen filling switch valve 117 can adjust the liquid oxygen filling speed, the third oxygen filling switch valve 115 is arranged in parallel with the first-stage liquid oxygen subcooler 02, the fourth oxygen filling switch valve 116 is arranged in parallel with the second-stage liquid oxygen subcooler 03, and when the third oxygen filling switch valve 115 and the fourth oxygen filling switch valve 116 are closed, the liquid oxygen is cooled by the two-stage subcooler and then enters the subcooled liquid oxygen storage device 04, when the third oxygen filling switch valve 115 and the fourth oxygen filling switch valve 116 are opened, the liquid oxygen can directly enter the subcooled liquid oxygen storage device 04, when the third oxygen filling switch valve 115 is closed and the fourth oxygen filling switch valve 116 is opened, part of the liquid oxygen is directly cooled by the first-stage liquid oxygen subcooler 02 and then enters the subcooled liquid oxygen storage device 04, and part of the liquid oxygen is cooled by the second-stage liquid oxygen subcooler 03 and then enters the subcooled liquid oxygen storage device 04, which can be used to adjust the mixing ratio of the subcooled liquid oxygen (80K) and the deeply subcooled liquid oxygen (66K), and the liquid oxygen temperature adjusting and filling can be realized without changing the parameters of the first-stage liquid oxygen subcooler 02 and the second-stage liquid oxygen subcooler 03, so that the two-stage deeply subcooled liquid oxygen large-flow filling system can realize the liquid oxygen temperature adjustment in a large range of 90K-66K, and the application range is wider.

[0023] Optionally, the liquid oxygen filling circulating pipeline 52 is further arranged, the sixth oxygen filling switch valve 118 is arranged between the fourth connecting point and the subcooled liquid oxygen storage device 04, the liquid oxygen filling circulating pipeline 52 is connected between the conventional liquid oxygen storage device 01 and the liquid oxygen filling main pipeline 51, the connecting point of the liquid oxygen filling circulating pipeline 52 and the liquid oxygen filling main pipeline 51 is located between the fourth connecting point and the sixth oxygen filling switch valve 118, and the seventh oxygen filling switch valve 521 is arranged on the liquid oxygen filling circulating pipeline 52. After the liquid oxygen in the conventional liquid oxygen storage device 01 is deeply subcooled by the first-stage liquid oxygen subcooler 02 and the second-stage liquid oxygen subcooler 03, the sixth oxygen filling switch valve 118 is opened and the seventh oxygen filling switch valve 521 is closed, the deeply subcooled liquid oxygen enters the subcooled liquid oxygen storage device 04, the sixth oxygen filling switch valve 118 is closed and the seventh oxygen filling switch valve 521 is opened, the deeply subcooled liquid oxygen enters the conventional liquid oxygen storage device 01, when the temperature of the liquid oxygen in the conventional liquid oxygen storage device 01 is lower than 80K, the first-stage filling switch valve 23 and the first-stage output switch valve 24 are closed, and the third oxygen filling switch valve 115 is opened, so that the deeply subcooled liquid oxygen can be prepared in real time without passing through the first-stage liquid oxygen subcooler 02. When the subcooled liquid oxygen needs to be prepared in advance or the subcooled liquid oxygen is long-term stored, the subcooled liquid oxygen can be circulated through the liquid oxygen filling circulating pipeline 52.

[0024] Optionally, the primary liquid oxygen subcooler 02 and the secondary liquid oxygen subcooler 03 are both plate-fin heat exchangers, the primary liquid oxygen subcooler 02 uses conventional low-temperature liquid nitrogen (77K) as the refrigerant medium, the secondary liquid oxygen subcooler 03 uses ultra-low-temperature liquid nitrogen (64K) as the refrigerant medium, the shell of the primary liquid oxygen subcooler 02 and the secondary liquid oxygen subcooler 03 is used to store the refrigerant medium, and the heat exchange tube in the shell of the primary liquid oxygen subcooler 02 and the secondary liquid oxygen subcooler 03 stores liquid oxygen. The primary liquid oxygen subcooler 02 and the secondary liquid oxygen subcooler 03 use liquid nitrogen staged filling technology to ensure that 64K subcooled liquid nitrogen can be stably provided during the deep subcooling of liquid oxygen.

[0025] Optionally, the present invention provides a two-stage deep subcooled liquid oxygen high-flow filling system, further comprising a liquid nitrogen storage device 61, a liquid nitrogen buffer device 62, a first-level liquid nitrogen filling branch pipe 25, a first-level nitrogen output branch pipe 26, a second-level liquid nitrogen filling branch pipe 35, and a second-level nitrogen output branch pipe 36. The first-level liquid oxygen subcooler 02 is provided with a first refrigerant inlet and a first refrigerant outlet, and the second-level liquid oxygen subcooler 03 is provided with a second refrigerant inlet and a second refrigerant outlet. The liquid nitrogen storage device 61 is connected to the first refrigerant inlet through the first-level liquid nitrogen filling branch pipe 25, and the first-level nitrogen output branch pipe 26 is connected to the first refrigerant outlet. The liquid nitrogen The liquid nitrogen in the storage device 61 is used as a refrigerant medium and enters the first-level liquid oxygen subcooler 02 through the first-level liquid nitrogen filling branch pipe 25 and the first refrigerant inlet. It exchanges heat with the liquid oxygen in the first-level liquid oxygen subcooler 02. Conventional liquid nitrogen (77K) is used in the first-level liquid oxygen subcooler 02 to subcool the liquid oxygen to a subcooled liquid oxygen temperature of about 80K. The liquid nitrogen is heated, and the nitrogen gas formed after the heating is discharged through the first refrigerant outlet and the first-level nitrogen output branch pipe 26. The liquid nitrogen buffer device 62 is connected to the first vacuum device. The liquid nitrogen buffer device 62 is vacuumed by the first vacuum device so that the internal pressure of the liquid nitrogen buffer device 62 reaches 0.012MPa ( The liquid nitrogen storage device 61 is connected to the inlet of the liquid nitrogen buffer device 62 through a connecting pipe 63. The connecting pipe 63 is provided with an on-off valve 631. When the on-off valve 631 is opened, the liquid nitrogen in the liquid nitrogen storage device 61 enters the liquid nitrogen buffer device 62. The liquid nitrogen in the liquid nitrogen buffer device 62 undergoes phase change to form nitrogen gas, which absorbs its own heat and reduces its own temperature from 77K to 64K to form supercooled liquid nitrogen. The liquid nitrogen buffer device 62 is connected to the second refrigerant inlet through the secondary liquid nitrogen filling branch pipe 35. The secondary nitrogen gas output branch pipe 36 is connected to the second refrigerant outlet. The supercooled liquid nitrogen in the liquid nitrogen buffer device 62 is Low-temperature nitrogen is used as a refrigerant medium and enters the secondary liquid oxygen subcooler 03 through the secondary liquid nitrogen filling branch pipe 35 and the second refrigerant inlet. In the secondary liquid oxygen subcooler 03, the subcooled liquid nitrogen (64K) exchanges heat with the subcooled liquid oxygen. After the heat exchange, the subcooled liquid oxygen is cooled to a deep subcooled liquid oxygen temperature of about 66K, and the subcooled liquid nitrogen is heated. The nitrogen formed by the heated liquid oxygen is discharged through the second refrigerant outlet and the secondary nitrogen output branch pipe 36. A switch valve 251, 261, 351, and 362 are respectively provided on the primary liquid nitrogen filling branch pipe 25, the primary nitrogen output branch pipe 26, the secondary liquid nitrogen filling branch pipe 35, and the secondary nitrogen output branch pipe 36. The first-stage liquid oxygen subcooler 02 is filled with conventional liquid nitrogen (77K) through the liquid nitrogen storage device 61, and the second-stage liquid oxygen subcooler 03 is filled with subcooled liquid nitrogen (64K) through the liquid nitrogen buffer device 62, which solves the problem of mixing of conventional liquid nitrogen and subcooled liquid nitrogen during deep refrigeration. The liquid nitrogen buffer device 62 can ensure a stable supply of subcooled liquid nitrogen during large-flow subcooling, while reducing the load of the vacuum pumping device.

[0026] Optionally, the two-stage deeply supercooled liquid oxygen large-flow filling system also comprises a second vacuumizing device, the output end of the secondary nitrogen output branch pipe is connected to the second vacuumizing device, and the second vacuumizing device vacuums the nitrogen in the inner cavity of the secondary liquid oxygen supercooling device 03 to a target vacuum degree. The vacuumizing mode meets the need of rapid evacuation and pressure reduction of the inner cavity of the secondary liquid oxygen supercooling device 03, accelerates the flow rate of the cooling medium, and further ensures that the two-stage deeply supercooled liquid oxygen large-flow filling system has the capability of directly and continuously producing 66K deeply supercooled liquid oxygen.

[0027] Optionally, the first vacuumizing device and the second vacuumizing device are two vacuum pumps 07 connected in parallel, the two vacuum pumps 07 are connected to the inner cavity of the liquid nitrogen buffering device 62 through the secondary nitrogen output branch pipe extension pipe 361 to vacuumize the inner cavity of the liquid nitrogen buffering device 62, and the secondary nitrogen output branch pipe extension pipe 361 is provided with a switch valve 362.

[0028] Optionally, the two-stage deeply supercooled liquid oxygen large-flow filling system also comprises a nitrogen exhaust tower 09 and a plurality of heat exchangers 08 connected in parallel, the output end of the secondary nitrogen output branch pipe 36 is connected to the input end of each heat exchanger 08, the output end of each heat exchanger 08 is connected to the input end of the vacuum pump 07, a flow regulating valve 81, 82, 83 or 84 is arranged between the output end of the secondary nitrogen output branch pipe 36 and each heat exchanger 08, the nitrogen in the secondary liquid oxygen supercooling device 03 enters the vacuum pump 07 after being warmed by the heat exchanger 08, the output end of the vacuum pump 07 and the primary nitrogen output branch pipe 26 are both connected to the nitrogen exhaust tower 09, and the nitrogen generated after being vacuumized and the nitrogen in the primary liquid oxygen supercooling device 02 are discharged at a high altitude through the nitrogen exhaust tower 09. The discharge speed of the nitrogen in the secondary liquid oxygen supercooling device 03 is controlled through the flow regulating valves 81, 82, 83 or 84, the temperature of the nitrogen in the secondary liquid oxygen supercooling device 03 is not lower than 273.15K after being warmed by the heat exchanger 08, and thus the adaptability of the vacuum pump is improved.

[0029] Optionally, the primary liquid nitrogen filling branch pipe 25 and the secondary liquid nitrogen filling branch pipe 35 are respectively provided with a temperature sensor, a pressure sensor and a flow meter, the primary liquid nitrogen filling branch pipe 25 is further provided with a flow regulating valve 252, the secondary liquid nitrogen filling branch pipe 35 is further provided with a flow regulating valve 352, the filling speed of the liquid nitrogen is monitored by the flow meter, the filling speed of the liquid nitrogen is controlled by the tank pressure and the opening degree of the regulating valve, and the liquid nitrogen is automatically supplemented to ensure that the liquid level is not lower than a target level.

[0030] Optionally, the liquid oxygen filling main pipeline 51 is respectively provided with a temperature sensor, a pressure sensor and a flow meter between the fourth connecting point and the supercooled liquid oxygen storage device 04 and between the conventional liquid oxygen storage device 01 and the fifth connecting point, real-time control of the filling flow, temperature and pressure of the liquid oxygen and liquid nitrogen is realized, and it is ensured that the primary liquid oxygen supercooling device 02, the secondary liquid oxygen supercooling device 03 and other equipment are in a designed state.

[0031] The above-described embodiments are merely intended to describe the preferred embodiments of the present application, and are not intended to limit the scope of the present application. Various changes and modifications made by those skilled in the art to the present application without departing from the spirit of the present application should fall within the scope of the present application defined by the claims.

Claims

1. A two-stage deep subcooled liquid oxygen high flowfill system characterized by, The application relates to a liquid oxygen supply system, which comprises a conventional liquid oxygen storage device (01), a first-stage liquid oxygen subcooler (02), a second-stage liquid oxygen subcooler (03), a subcooled liquid oxygen storage device (04), a liquid oxygen filling main pipeline (51), a first-stage liquid oxygen filling branch pipeline (21), a first-stage liquid oxygen output branch pipeline (22), a second-stage liquid oxygen filling branch pipeline (31), a second-stage liquid oxygen output branch pipeline (32), a liquid oxygen mixing device arranged in the subcooled liquid oxygen storage device (04), the liquid oxygen filling main pipeline (51) being connected between the conventional liquid oxygen storage device (01) and the subcooled liquid oxygen storage device (04), the first-stage liquid oxygen subcooler (02) being used for cooling liquid oxygen in the conventional liquid oxygen storage device (01) into subcooled liquid oxygen, the second-stage liquid oxygen subcooler (03) being used for cooling the subcooled liquid oxygen into deep subcooled liquid oxygen, the first-stage liquid oxygen filling branch pipeline (21), the first-stage liquid oxygen output branch pipeline (22), the second-stage liquid oxygen filling branch pipeline (31) and the second-stage liquid oxygen output branch pipeline (32) being respectively provided with a first-stage filling on-off valve (23), a first-stage output on-off valve (24), a second-stage filling on-off valve (33) and a second-stage output on-off valve (34), the first-stage liquid oxygen filling branch pipeline (21) being connected between the liquid oxygen filling main pipeline (51) and a liquid oxygen inlet of the first-stage liquid oxygen subcooler (02), the first-stage liquid oxygen output branch pipeline (22) being connected between a liquid oxygen outlet of the first-stage liquid oxygen subcooler (02) and the liquid oxygen filling main pipeline (51), the second-stage liquid oxygen filling branch pipeline (31) being connected between the liquid oxygen filling main pipeline (51) and a liquid oxygen inlet of the second-stage liquid oxygen subcooler (03), the second-stage liquid oxygen output branch pipeline (32) being connected between a liquid oxygen outlet of the second-stage liquid oxygen subcooler (03) and the liquid oxygen filling main pipeline (51), the connection points of the first-stage liquid oxygen filling branch pipeline (21), the first-stage liquid oxygen output branch pipeline (22), the second-stage liquid oxygen filling branch pipeline (31) and the second-stage liquid oxygen output branch pipeline (32) with the liquid oxygen filling main pipeline (51) being respectively a first connection point, a second connection point, a third connection point and a fourth connection point, the first connection point, the second connection point, the third connection point and the fourth connection point being sequentially arranged along the liquid oxygen filling main pipeline (51) from an upstream to a downstream, the system further comprises a liquid nitrogen storage device (61), a liquid nitrogen buffer device (62), a first-stage liquid nitrogen filling branch pipeline (25), a first-stage nitrogen output branch pipeline (26), a second-stage liquid nitrogen filling branch pipeline (35) and a second-stage nitrogen output branch pipeline (36), the first-stage liquid oxygen subcooler (02) is provided with a first refrigerant inlet and a first refrigerant outlet, the second-stage liquid oxygen subcooler (03) is provided with a second refrigerant inlet and a second refrigerant outlet, the liquid nitrogen storage device (61) is connected to the first refrigerant inlet through the first-stage liquid nitrogen filling branch pipeline (25), the first-stage liquid nitrogen output branch pipeline (26) is connected to the first refrigerant outlet, and the second-stage liquid nitrogen filling branch pipeline (35) is connected to the second refrigerant inlet.The liquid nitrogen in the liquid nitrogen storage device (61) enters the first liquid oxygen subcooler (02) through the first liquid nitrogen filling branch pipe (25) and the first coolant inlet as a coolant medium, exchanges heat with the liquid oxygen in the first liquid oxygen subcooler (02), and after the heat exchange, the liquid oxygen is cooled to supercooled liquid oxygen, and the liquid nitrogen is warmed to form nitrogen gas, and after the warming, the nitrogen gas is discharged through the first coolant outlet and the first nitrogen gas output branch pipe (26). The liquid nitrogen buffer device (62) is connected to the first vacuum pumping device, the first vacuum pumping device pumps the liquid nitrogen buffer device (62) to vacuum, the liquid nitrogen storage device (61) is connected to the inlet of the liquid nitrogen buffer device (62) through the connecting pipe (63), the outlet of the liquid nitrogen buffer device (62) is connected to the second coolant inlet through the second liquid nitrogen filling branch pipe (35), the second nitrogen gas output branch pipe (36) is connected to the second coolant outlet, and the liquid nitrogen in the liquid nitrogen storage device (61) enters the liquid nitrogen buffer device (62). The liquid nitrogen in the liquid nitrogen buffer device (62) absorbs its own heat to form supercooled liquid nitrogen, the supercooled liquid nitrogen enters the second liquid oxygen subcooler (03) through the second liquid nitrogen filling branch pipe (35) and the second coolant inlet as a coolant medium, exchanges heat with the supercooled liquid oxygen in the second liquid oxygen subcooler (03), and after the heat exchange, the supercooled liquid oxygen is cooled to deep supercooled liquid oxygen, and the supercooled liquid nitrogen is warmed, and the nitrogen gas after the warming is discharged through the second coolant outlet and the second nitrogen gas output branch pipe (36). A switch valve (251, 261, 351, 362) is arranged on the first liquid nitrogen filling branch pipe (25), the first nitrogen gas output branch pipe (26), the second liquid nitrogen filling branch pipe (35), and the second nitrogen gas output branch pipe (36), respectively.

2. The two-stage deep subcooled liquid oxygen high flowfill system of claim 1, wherein, The liquid oxygen pump (11) is connected to the liquid oxygen filling main pipeline (51) through the liquid oxygen pump inlet branch pipe (111) at an inlet end of the liquid oxygen pump (11), and is connected to the liquid oxygen filling main pipeline (51) through the liquid oxygen pump outlet branch pipe (112) at an outlet end of the liquid oxygen pump (11). The first oxygen filling on-off valve (113) is arranged on the liquid oxygen pump inlet branch pipe (111). The connection point of the liquid oxygen pump inlet branch pipe (111) and the liquid oxygen filling main pipeline (51) is a fifth connection point. The connection point of the liquid oxygen pump outlet branch pipe (112) and the liquid oxygen filling main pipeline (51) is a sixth connection point. The fifth connection point and the sixth connection point are located between the conventional liquid oxygen storage device (01) and the first connection point. The second oxygen filling on-off valve (114) is arranged on the liquid oxygen filling main pipeline (51) between the fifth connection point and the sixth connection point.

3. The two-stage deep subcooled liquid oxygen high flowfill system of claim 2, wherein, The third oxygen filling on-off valve (115), the fourth oxygen filling on-off valve (116) and the fifth oxygen filling on-off valve (117) are arranged on the liquid oxygen filling main pipeline (51) between the first connection point and the second connection point, between the third connection point and the fourth connection point, and between the sixth connection point and the first connection point, respectively. The fifth oxygen filling on-off valve (117) is a flow regulating valve.

4. The two-stage deep subcooled liquid oxygen high flowfill system of claim 3, wherein, The sixth oxygen filling on-off valve (118) is arranged between the fourth connection point and the supercooled liquid oxygen storage device (04). The liquid oxygen filling circulating pipeline (52) is connected between the conventional liquid oxygen storage device (01) and the liquid oxygen filling main pipeline (51). The connection point of the liquid oxygen filling circulating pipeline (52) and the liquid oxygen filling main pipeline (51) is located between the fourth connection point and the sixth oxygen filling on-off valve (118).

5. The two-stage deep subcooled liquid oxygen high flowfill system of claim 4, wherein, The primary liquid oxygen supercooler (02) and the secondary liquid oxygen supercooler (03) are both plate-fin heat exchangers. The primary liquid oxygen supercooler (02) uses low-temperature liquid nitrogen as a refrigerant medium, and the secondary liquid oxygen supercooler (03) uses ultralow-temperature liquid nitrogen as a refrigerant medium.

6. The two-stage deep subcooled liquid oxygen high-flow fuelling system of claim 5, wherein, The second vacuumizing device is connected to the output end of the secondary nitrogen gas output branch pipe (36). The second vacuumizing device vacuumizes the inner cavity of the secondary liquid oxygen supercooler (03) to a target vacuum degree.

7. The two-stage deep subcooled liquid oxygen high-flow fuelling system of claim 6, wherein, The first vacuumizing device and the second vacuumizing device are both two vacuum pumps (07) connected in parallel. The vacuum pump (07) is connected to the inner cavity of the liquid nitrogen buffer device (62) through the secondary nitrogen gas output branch pipe extension pipe (361) to vacuumize the liquid nitrogen buffer device (62).

8. The two-stage deep subcooled liquid oxygen high-flow fuelling system of claim 7, wherein, The nitrogen exhaust tower (09) and a plurality of heat exchangers (08) in parallel are further included, the output end of the secondary nitrogen output branch pipe (36) is connected to the input end of each heat exchanger (08), the output end of each heat exchanger (08) is connected to the input end of the vacuum pump (07), a flow regulating valve (81, 82, 83, 84) is arranged between the output end of the secondary nitrogen output branch pipe (36) and each heat exchanger (08), and the output end of the vacuum pump (07) and the primary nitrogen output branch pipe (26) are connected to the nitrogen exhaust tower (09).

9. The two-stage deep subcooled liquid oxygen high-flow fuelling system of claim 8, wherein, Temperature sensors, pressure sensors and flow meters are arranged on the primary liquid nitrogen filling branch pipe (25) and the secondary liquid nitrogen filling branch pipe (35), and flow regulating valves (252, 352) are further arranged on the primary liquid nitrogen filling branch pipe (25) and the secondary liquid nitrogen filling branch pipe (35), and temperature sensors, pressure sensors and flow meters are arranged on the liquid oxygen filling main pipeline between the fourth connecting point and the supercooled liquid oxygen storage device (04) and between the conventional liquid oxygen storage device (01) and the fifth connecting point.

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