A parallel precooling liquid hydrogen filling system and method

Abstract

The present invention discloses a parallel precooling liquid hydrogen filling system and method thereof, belonging to the field of liquid hydrogen technology. The liquid hydrogen filling system includes a high-pressure precooling pipeline, a high-pressure liquid hydrogen tank, a low-pressure precooling pipeline, a low-pressure liquid hydrogen tank, a pipe valve subsystem, a liquid hydrogen filling box, and an ejection subsystem; the ejection subsystem includes an ejection pipeline and a hydrogen ejector. The system can reduce the precooling time and improve the precooling efficiency: by synchronously precooling the liquid hydrogen filling pipeline and the liquid hydrogen filling box in parallel, the overall precooling time of the system can be significantly reduced; for liquid hydrogen filling boxes with long precooling times, the use of an external liquid hydrogen tank for direct spray cooling can effectively avoid the generation of air film during the traditional precooling process, thereby reducing the problem of precooling efficiency; by separately setting high-pressure precooling and low-pressure precooling, and using the hydrogen ejector component, the internal pressure of the liquid hydrogen filling box can be reduced, the vaporization efficiency of the atomized liquid hydrogen can be further improved, and the overall cooling of the liquid hydrogen filling box can be accelerated.

Description

Technical Field

[0001] The invention belongs to the technical field of liquid hydrogen, and in particular relates to a parallel precooling liquid hydrogen filling system and a method thereof. Background Art

[0002] The main function of the liquid hydrogen filling system is to complete the filling, leakage, signal joint test and pipeline air tightness inspection of liquid hydrogen for the launch vehicle. The system ensures the safe discharge of liquid hydrogen and hydrogen gas, and realizes the transfer of liquid hydrogen from the storage tank to the target tank. The liquid hydrogen filling process system usually consists of a storage tank, a flow meter, various valves and pipelines. Due to the low density of liquid hydrogen, it is usually filled by extrusion.

[0003] The filling process of the liquid hydrogen filling system mainly includes the steps of overall replacement, precooling, filling and shedding. Among them, the precooling stage refers to the first filling of a small amount of liquid hydrogen into the system after the replacement is completed. After entering the system, these liquid hydrogens will absorb heat, vaporize and be emptied, thereby gradually reducing the temperature of the entire system to the liquid hydrogen temperature, effectively reducing the loss of liquid hydrogen during the filling process. However, in the early stage of precooling, due to the high temperature of the pipeline and the container, the contact between the wall and the low-temperature medium during the precooling process causes violent boiling and vaporization. This will form an air film on the surface of some containers, reduce the heat transfer coefficient, and thus prolong the precooling time. Therefore, in order to improve the efficiency of the liquid hydrogen filling system and meet the growing demand for liquid hydrogen use, it is urgent to design a more efficient precooling system and method. Summary of the invention

[0004] The purpose of the present invention is to solve the deficiencies in the prior art and provide a parallel precooling liquid hydrogen filling system and method thereof. The system performs parallel precooling on the filling pipeline and the filling box, and uses differential pressure design and other technologies to adopt a decompression spray cooling method when precooling the filling box to avoid the phenomenon of weakened heat exchange of the air film.

[0005] The specific technical solutions adopted by the present invention are as follows:

[0006] In a first aspect, the present invention provides a parallel precooling liquid hydrogen filling system, comprising a high-pressure precooling pipeline, a high-pressure liquid hydrogen tank, a low-pressure precooling pipeline, a low-pressure liquid hydrogen tank, a pipe valve subsystem, a liquid hydrogen filling box, and an ejection subsystem; the ejection subsystem comprises an ejection pipeline and a hydrogen ejector;

[0007] The high-pressure precooling pipeline is the original filling pipeline, which is connected in sequence to the high-pressure liquid hydrogen tank, the high-pressure liquid hydrogen stop valve, the pipe valve subsystem, the liquid hydrogen three-way valve and the ejection pipeline in the ejection subsystem; the low-pressure precooling pipeline is a newly added filling pipeline, which is connected in sequence to the low-pressure liquid hydrogen tank, the low-pressure liquid hydrogen stop valve, the liquid hydrogen atomizing valve and the atomizing nozzle array in the liquid hydrogen filling tank, and the liquid hydrogen in the low-pressure liquid hydrogen tank is input into the liquid hydrogen filling tank by atomization; a branch with a liquid hydrogen mixing valve is provided between the high-pressure precooling pipeline and the low-pressure precooling pipeline, so that the high-pressure liquid hydrogen tank and the low-pressure liquid hydrogen tank are connected in parallel to achieve common filling;

[0008] The top of the liquid hydrogen filling tank is provided with three interfaces, the first interface is connected to the liquid hydrogen atomization valve on the low-pressure precooling pipeline, the second interface is connected to the emptying pipeline, and the third interface is connected to the boosting pipeline; the emptying pipeline and the boosting pipeline are respectively provided with an emptying valve and a boosting valve; the bottom of the liquid hydrogen filling tank is provided with a fourth interface and a fifth interface, the fourth interface is connected to the filling pipeline, and the fifth interface is connected to the supply pipeline; the filling pipeline and the supply pipeline are respectively provided with a liquid hydrogen filling valve and a liquid hydrogen supply valve;

[0009] The front end of the ejector pipeline is divided into a first branch and a second branch. The inlet of the first branch is connected to the liquid hydrogen three-way valve in the high-pressure precooling pipeline, and the high-pressure hydrogen is used as the primary fluid of the hydrogen ejector; a primary flow inlet valve is provided on the first branch; the inlet of the second branch is connected to the filling pipeline, and the low-pressure hydrogen from the liquid hydrogen filling tank is used as the secondary fluid of the hydrogen ejector; a secondary flow inlet valve is provided on the second branch.

[0010] Preferably, the hydrogen ejector comprises a primary fluid nozzle, a secondary fluid pipeline, a suction chamber, a mixing tube and a diffusion tube; the primary fluid nozzle receives high-pressure hydrogen from the high-pressure precooling pipeline, so that the suction chamber forms a low-pressure area; under the action of the pressure difference, the secondary fluid pipeline inhales low-pressure hydrogen from the liquid hydrogen filling tank, so that the low-pressure hydrogen and the high-pressure hydrogen are mixed in the mixing tube, and are discharged to the outside after the flow rate is reduced in the diffusion tube.

[0011] Preferably, the pipe-valve subsystem comprises a liquid hydrogen valve and a liquid hydrogen metering unit which are connected in sequence.

[0012] Furthermore, the liquid hydrogen valve is a ball valve, a stop valve, a regulating valve or a safety valve.

[0013] Furthermore, the liquid hydrogen metering unit adopts a mass flow meter, a liquid level meter, a flow meter, a temperature sensor or a pressure sensor.

[0014] Preferably, the pipe-valve subsystem further comprises a liquid hydrogen functional component arranged between the liquid hydrogen valve and the liquid hydrogen metering unit, and the liquid hydrogen functional component is a pressure regulating component, a temperature regulating component or a pump component.

[0015] Preferably, the atomizing nozzle array includes a plurality of rotatable atomizing nozzles, which input the liquid hydrogen from the low-pressure liquid hydrogen tank into the liquid hydrogen filling tank at multiple angles for cooling.

[0016] Preferably, the outlet of the supply pipeline is provided with a flange for connecting to external equipment.

[0017] Preferably, the high-pressure precooling pipeline, the low-pressure precooling pipeline and the liquid hydrogen filling tank are provided with insulating materials outside to prevent heat leakage; the high-pressure liquid hydrogen tank and the low-pressure liquid hydrogen tank adopt a self-pressurization method to transport liquid hydrogen.

[0018] In a second aspect, the present invention provides a method for filling a liquid hydrogen system using the parallel precooling method of the first aspect, comprising a precooling stage and a filling stage;

[0019] The precooling stage is specifically as follows:

[0020] Open the high-pressure liquid hydrogen stop valve, the liquid hydrogen valve in the pipe valve subsystem and the primary flow inlet valve, and the liquid hydrogen three-way valve connects the pipe valve subsystem and the primary flow inlet valve; the high-pressure liquid hydrogen tank enters the high-pressure liquid supply state through self-pressurization, and the high-pressure liquid hydrogen enters the pipe valve subsystem through the high-pressure liquid hydrogen stop valve and is converted into high-pressure hydrogen to achieve overall precooling of the pipe valve subsystem; then the high-pressure hydrogen enters the primary fluid nozzle of the hydrogen ejector through the liquid hydrogen three-way valve and the primary flow inlet valve;

[0021] Open the low-pressure liquid hydrogen shut-off valve, liquid hydrogen atomizing valve, liquid hydrogen filling valve and secondary flow inlet valve; the low-pressure liquid hydrogen tank enters the low-pressure liquid supply state through self-pressurization, and the low-pressure liquid hydrogen enters the atomizing nozzle array through the low-pressure liquid hydrogen shut-off valve and the liquid hydrogen atomizing valve. The atomized liquid hydrogen particles quickly vaporize into low-pressure hydrogen after contacting the wall of the liquid hydrogen filling tank; then the low-pressure hydrogen enters the secondary fluid pipeline of the hydrogen ejector through the liquid hydrogen filling valve and the secondary flow inlet valve;

[0022] The hydrogen ejector starts to operate, the primary fluid nozzle receives the high-pressure hydrogen from the high-pressure precooling pipeline and the low-pressure hydrogen sucked from the secondary fluid pipeline, mixes them in the mixing tube, and then reduces the flow rate in the diffusion tube and discharges them to the outside; until the medium passing through the primary flow inlet valve and the secondary flow inlet valve is all liquid hydrogen, the precooling is completed, and the liquid hydrogen atomization valve, the primary flow inlet valve, and the secondary flow inlet valve are closed;

[0023] The filling phases are as follows:

[0024] The high-pressure liquid hydrogen tank is converted into a low-pressure liquid supply state by self-pressurization, and the drain valve and the liquid hydrogen mixing valve are opened; the liquid hydrogen three-way valve is connected to the pipe valve subsystem and the liquid hydrogen filling valve, and the liquid hydrogen medium from the high-pressure liquid hydrogen tank is combined with the liquid hydrogen medium from the low-pressure liquid hydrogen tank through the liquid hydrogen mixing valve, and then enters the liquid hydrogen filling tank through the pipe valve subsystem, the liquid hydrogen three-way valve, and the liquid hydrogen filling valve for liquid hydrogen filling; the hydrogen generated during the filling process is emptied through the drain valve;

[0025] When the liquid hydrogen inside the liquid hydrogen filling tank reaches the target liquid level, close the high-pressure liquid hydrogen shut-off valve, liquid hydrogen valve, low-pressure liquid hydrogen shut-off valve, liquid hydrogen filling valve and liquid hydrogen mixing valve, keep the drain valve normally open, and the filling is completed.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The liquid hydrogen filling system provided by the present invention can reduce the precooling time and improve the precooling efficiency. By precooling the liquid hydrogen filling pipeline and the liquid hydrogen filling tank synchronously in parallel, the overall precooling time of the system can be significantly reduced; for liquid hydrogen filling tanks with long precooling times, the use of external liquid hydrogen tanks for direct spray cooling can effectively avoid the problem of gas film generation during traditional precooling, thereby reducing the precooling efficiency; by separately setting high-pressure precooling and low-pressure precooling, and using hydrogen ejector components, the internal pressure of the liquid hydrogen filling tank can be reduced, further improving the vaporization efficiency of the atomized liquid hydrogen, and accelerating the overall cooling of the liquid hydrogen filling tank;

[0028] (2) The liquid hydrogen filling system provided by the present invention is provided with an ejection subsystem with a hydrogen ejector as the core, which has the advantages of no need for external energy consumption, convenient movement and disassembly, and reusability, thereby increasing the flexibility and economy of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of the structure of a liquid hydrogen filling system with parallel precooling provided in an embodiment of the present invention;

[0030] Figure 2 A schematic diagram of the structure of a liquid hydrogen filling system with parallel precooling provided in another embodiment of the present invention;

[0031] In the figure: high-pressure precooling pipeline 1, high-pressure liquid hydrogen tank 2, high-pressure liquid hydrogen stop valve 3, pipe valve subsystem 4, liquid hydrogen valve 5, liquid hydrogen functional component 6, liquid hydrogen metering unit 7, liquid hydrogen three-way valve 8, low-pressure precooling pipeline 9, low-pressure liquid hydrogen tank 10, low-pressure liquid hydrogen stop valve 11, liquid hydrogen atomizing valve 12, liquid hydrogen filling tank 13, atomizing nozzle array 14, drain valve 15, boost valve 16, liquid hydrogen filling valve 17, liquid hydrogen supply valve 18, flange 19, ejection subsystem 20, ejection pipeline 21, primary flow inlet valve 22, secondary flow inlet valve 23, hydrogen ejector 24, liquid hydrogen mixing valve 25. DETAILED DESCRIPTION

[0032] In order to make the above-mentioned purpose, features and advantages of the present invention more obvious and easy to understand, the specific implementation mode of the present invention is described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below. The technical features in each embodiment of the present invention can be combined accordingly without conflicting with each other.

[0033] In the description of the present invention, it is to be understood that when an element is considered to be "connected" to another element, it may be directly connected to the other element or indirectly connected, that is, there are intermediate elements. On the contrary, when an element is said to be "directly" connected to another element, there are no intermediate elements.

[0034] In the description of the present invention, it should be understood that the terms "first" and "second" are only used for the purpose of distinguishing descriptions, and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features.

[0035] In the description of the present invention, it should be understood that the terms "high pressure" and "low pressure" (such as "high pressure hydrogen" and "low pressure hydrogen") refer to high pressure or low pressure compared to the pressure of the same medium in the same passage, and cannot be understood as indicating or implying relative importance or implicitly indicating the pressure value of the indicated technical feature.

[0036] like Figure 1 As shown, in a preferred embodiment of the present invention, a parallel precooling liquid hydrogen filling system is provided. The system includes a high-pressure precooling pipeline 1, a high-pressure liquid hydrogen tank 2, a low-pressure precooling pipeline 9, a low-pressure liquid hydrogen tank 10, a pipe valve subsystem 4, a liquid hydrogen filling box 13, and an ejection subsystem 20. The ejection subsystem 20 includes an ejection pipeline 21 and a hydrogen ejector 24.

[0037] In the system of the present invention, the high-pressure precooling pipeline 1 is the original filling pipeline, which is connected in sequence to the high-pressure liquid hydrogen tank 2, the high-pressure liquid hydrogen stop valve 3, the pipe-valve subsystem 4, the liquid hydrogen three-way valve 8 and the ejection pipeline 21 in the ejection subsystem 20, so as to realize efficient precooling of the pipe-valve subsystem 4 and use the exhausted high-pressure hydrogen as the primary fluid of the hydrogen ejector 24.

[0038] In another embodiment provided by the present invention, the pipe-valve subsystem 4 includes a liquid hydrogen valve 5, a liquid hydrogen functional component 6 and a liquid hydrogen metering unit 7, representing a collection of various pipe-valve parts at the front end of the liquid hydrogen filling system.

[0039] It should be noted that the liquid hydrogen valve is a common valve in the liquid hydrogen filling system, which is used to control and manage the flow of liquid hydrogen. In the liquid hydrogen filling system, the main function of these valves is to ensure that the liquid hydrogen can be safely and effectively transferred from the storage container to another container or system. Since liquid hydrogen can only remain liquid at extremely low temperatures, these valves must be able to withstand extreme low temperature environments. The present invention does not specifically limit the specific type and material of the liquid hydrogen valve. Those skilled in the art can select valves suitable for the liquid hydrogen filling system according to specific working conditions, such as ball valves, stop valves, regulating valves or safety valves.

[0040] It should be noted that the liquid hydrogen functional components can be pressure control components, temperature control components or pump components. The present invention does not limit the specific form of the liquid hydrogen functional components. Those skilled in the art can select appropriate functional components based on the liquid hydrogen conditions required by the rear-end ejection subsystem. Specifically, a pressure buffer tank, a heat exchanger or a liquid hydrogen pump can be selected. The selection and configuration of these components depends on the specific system design and operating requirements. When designing a liquid hydrogen filling system, it is necessary to comprehensively consider the performance indicators of these components and their coordination with each other to ensure the safe, stable and efficient operation of the system.

[0041] It should be noted that the liquid hydrogen metering unit is a device in the liquid hydrogen filling system responsible for accurately measuring the liquid hydrogen flow rate to ensure that the liquid hydrogen filling process is accurate and efficient. The present invention does not specifically limit the specific type and material of the liquid hydrogen metering unit. Those skilled in the art can select a suitable metering unit according to specific working conditions, such as a mass flow meter, a liquid level meter, a flow meter, a temperature sensor or a pressure sensor.

[0042] In the system of the present invention, the low-pressure precooling pipeline 9 is a newly added filling pipeline, which is connected in sequence to the low-pressure liquid hydrogen tank 10, the low-pressure liquid hydrogen stop valve 11, the liquid hydrogen atomizing valve 12 and the atomizing nozzle array 14 in the liquid hydrogen filling tank 13, and the low-pressure liquid hydrogen in the low-pressure liquid hydrogen tank 10 is input into the liquid hydrogen filling tank 13 by atomization.

[0043] In the system of the present invention, the atomizing nozzle array 14 includes a plurality of rotatable atomizing nozzles. The atomizing nozzles can subdivide the liquid hydrogen into tiny droplets. Tiny liquid hydrogen droplets are more easily evaporated into a gaseous state, which is very important for the rapid conversion and utilization of liquid hydrogen. Multiple rotatable atomizing nozzles can input the liquid hydrogen from the low-pressure liquid hydrogen tank 10 into the liquid hydrogen filling tank 13 for cooling at multiple angles.

[0044] In the system of the present invention, three interfaces are arranged on the top of the liquid hydrogen filling tank 13, the first interface is connected to the liquid hydrogen atomizing valve 12 on the low-pressure precooling pipeline 9, the second interface is connected to the emptying pipeline, and the third interface is connected to the boosting pipeline. Among them, an emptying valve 15 is arranged on the emptying pipeline, and a boosting valve 16 is arranged on the boosting pipeline. The fourth interface and the fifth interface are arranged at the bottom of the liquid hydrogen filling tank 13, the fourth interface is connected to the filling pipeline, and the fifth interface is connected to the supply pipeline. A liquid hydrogen filling valve 17 is arranged on the filling pipeline, and a liquid hydrogen supply valve 18 is arranged on the supply pipeline.

[0045] In the system of the present invention, the outlet of the supply pipeline is provided with a flange 19 for connecting an external device. It should be noted that the external device may be a pressure regulator to ensure that the liquid hydrogen maintains a constant pressure during transportation, or a temperature sensor to ensure that the liquid hydrogen is stored and transported at a suitable low temperature, and other devices. Those skilled in the art may make a selection according to different conditions.

[0046] In the system of the present invention, the front end of the ejector pipeline 21 is divided into a first branch and a second branch. The inlet of the first branch is connected to the liquid hydrogen three-way valve 8 in the high-pressure precooling pipeline 1, and the high-pressure hydrogen is used as the primary fluid of the hydrogen ejector 24. The inlet of the second branch is connected to the filling pipeline, and the low-pressure hydrogen from the liquid hydrogen filling tank 13 is used as the secondary fluid of the hydrogen ejector 24. In this embodiment, a primary flow inlet valve 22 is provided on the first branch, and a secondary flow inlet valve 23 is provided on the second branch.

[0047] In the system of the present invention, the hydrogen ejector 24 includes a primary fluid nozzle, a secondary fluid pipeline, an inhalation chamber, a mixing tube and a diffusion tube. The primary fluid nozzle receives high-pressure hydrogen from the high-pressure precooling pipeline 1, so that the inhalation chamber forms a low-pressure area. Under the action of the pressure difference, the secondary fluid pipeline inhales low-pressure hydrogen from the liquid hydrogen filling tank 13, so that the low-pressure hydrogen and the high-pressure hydrogen are mixed in the mixing tube, and the flow rate is reduced in the diffusion tube before being discharged to the outside.

[0048] In the system of the present invention, a branch is provided between the high-pressure precooling pipeline 1 and the low-pressure precooling pipeline 9, and a liquid hydrogen mixing valve 25 is provided on the branch, so that the high-pressure liquid hydrogen tank 2 and the low-pressure liquid hydrogen tank 10 are connected in parallel to achieve common filling.

[0049] Liquid hydrogen is a very low temperature liquid, so thermal management during its storage and transportation is very important. In order to maintain the low temperature state and reduce heat loss during the transportation of liquid hydrogen, in this embodiment, insulation materials are provided outside the high pressure precooling pipeline 1, the low pressure precooling pipeline 9 and the liquid hydrogen filling tank 13 to avoid heat loss.

[0050] In the system of the present invention, both the high-pressure liquid hydrogen tank 2 and the low-pressure liquid hydrogen tank 10 use a self-pressurization method to transport liquid hydrogen. The self-pressurization method can automatically adjust the pressure according to the consumption of liquid hydrogen, without the need for external energy or complex control systems, reducing dependence on pumps and other mechanical equipment, and reducing energy consumption and maintenance costs. In addition, since liquid hydrogen is transported within a closed system by its own pressure, the risk of leakage and external contamination is reduced.

[0051] The present invention also provides a method for filling a liquid hydrogen system using parallel precooling, including a precooling stage and a filling stage. Assume that the system has completed replacement, all valves are closed, and all devices are stopped.

[0052] (1) The precooling stage is as follows:

[0053] Open the high-pressure liquid hydrogen stop valve 3, the liquid hydrogen valve 5 in the pipe valve subsystem 4 and the primary flow inlet valve 22, and the liquid hydrogen three-way valve 8 connects the pipe valve subsystem 4 and the primary flow inlet valve 22. The high-pressure liquid hydrogen tank 2 enters the high-pressure liquid supply state through self-pressurization, and the high-pressure liquid hydrogen flows through the high-pressure liquid hydrogen stop valve 3, flows through the liquid hydrogen valve 5, the liquid hydrogen functional component 6, and the liquid hydrogen metering unit 7 in sequence, and is converted from liquid hydrogen to high-pressure hydrogen gas, realizing the overall precooling of the front-end pipe valve subsystem 4. Subsequently, the high-pressure hydrogen enters the primary fluid nozzle of the hydrogen ejector 24 through the liquid hydrogen three-way valve 8 and the primary flow inlet valve 22.

[0054] Open the low-pressure liquid hydrogen stop valve 11, the liquid hydrogen atomizing valve 12, the liquid hydrogen filling valve 17 and the secondary flow inlet valve 23. The low-pressure liquid hydrogen tank 10 enters the low-pressure liquid supply state through self-pressurization, and the low-pressure liquid hydrogen enters the atomizing nozzle array 14 through the low-pressure liquid hydrogen stop valve 11 and the liquid hydrogen atomizing valve 12. The atomized liquid hydrogen particles quickly vaporize into low-pressure hydrogen after contacting the wall of the liquid hydrogen filling tank 13. Then the low-pressure hydrogen enters the secondary fluid pipeline of the hydrogen ejector 24 through the liquid hydrogen filling valve 17 and the secondary flow inlet valve 23.

[0055] The hydrogen ejector 24 starts to operate, and the primary fluid nozzle receives the high-pressure hydrogen from the high-pressure precooling pipeline 1 and the low-pressure hydrogen sucked from the secondary fluid pipeline, mixes them in the mixing tube, and then reduces the flow rate in the diffusion tube and discharges them to the outside.

[0056] The above process continues until the medium passing through the primary flow inlet valve 22 and the secondary flow inlet valve 23 is all liquid hydrogen, the precooling is completed, and the liquid hydrogen atomization valve 12, the primary flow inlet valve 22, and the secondary flow inlet valve 23 are closed.

[0057] (2) The filling phase is as follows:

[0058] The high-pressure liquid hydrogen tank 2 is converted to a low-pressure liquid supply state by self-pressurization, and the drain valve 15 and the liquid hydrogen mixing valve 25 are opened. The liquid hydrogen three-way valve 8 connects the pipe valve subsystem 4 and the liquid hydrogen filling valve 17. The liquid hydrogen medium from the high-pressure liquid hydrogen tank 2 is combined with the liquid hydrogen medium from the low-pressure liquid hydrogen tank 10 through the liquid hydrogen mixing valve 25, and then enters the liquid hydrogen filling tank 13 through the liquid hydrogen valve 5, the liquid hydrogen functional component 6, the liquid hydrogen metering unit 7, the liquid hydrogen three-way valve 8, and the liquid hydrogen filling valve 17 in sequence for liquid hydrogen filling. The hydrogen generated during the filling process is discharged through the drain valve 15.

[0059] When the liquid hydrogen in the liquid hydrogen filling tank 13 reaches the target liquid level, the high-pressure liquid hydrogen stop valve 3, the liquid hydrogen valve 5, the low-pressure liquid hydrogen stop valve 11, the liquid hydrogen filling valve 17 and the liquid hydrogen mixing valve 25 are closed, and the drain valve 15 remains normally open, and the filling is completed.

[0060] The above-described embodiment is only a preferred solution of the present invention, but it is not intended to limit the present invention. A person skilled in the relevant technical field may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present invention.

Claims

1. A parallel precooling liquid hydrogen filling system, characterized in that: It comprises a high-pressure precooling pipeline (1), a high-pressure liquid hydrogen tank (2), a low-pressure precooling pipeline (9), a low-pressure liquid hydrogen tank (10), a pipe valve subsystem (4), a liquid hydrogen filling box (13), and an ejection subsystem (20); the ejection subsystem (20) comprises an ejection pipeline (21) and a hydrogen ejector (24); The high-pressure precooling pipeline (1) is an original filling pipeline, which is sequentially connected to the high-pressure liquid hydrogen tank (2), the high-pressure liquid hydrogen stop valve (3), the pipe valve subsystem (4), the liquid hydrogen three-way valve (8) and the ejection pipeline (21) in the ejection subsystem (20); the low-pressure precooling pipeline (9) is a newly added filling pipeline, which is sequentially connected to the low-pressure liquid hydrogen tank (10), the low-pressure liquid hydrogen stop valve (11), the liquid hydrogen atomizing valve (12) and the atomizing nozzle array (14) in the liquid hydrogen filling tank (13), and the liquid hydrogen in the low-pressure liquid hydrogen tank (10) is input into the liquid hydrogen filling tank (13) by atomization; a branch with a liquid hydrogen mixing valve (25) is provided between the high-pressure precooling pipeline (1) and the low-pressure precooling pipeline (9), so that the high-pressure liquid hydrogen tank (2) and the low-pressure liquid hydrogen tank (10) are connected in parallel to achieve common filling; The top of the liquid hydrogen filling box (13) is provided with three interfaces, the first interface is connected to the liquid hydrogen atomizing valve (12) on the low-pressure precooling pipeline (9), the second interface is connected to the emptying pipeline, and the third interface is connected to the boosting pipeline; the emptying pipeline and the boosting pipeline are respectively provided with an emptying valve (15) and a boosting valve (16); the bottom of the liquid hydrogen filling box (13) is provided with a fourth interface and a fifth interface, the fourth interface is connected to the filling pipeline, and the fifth interface is connected to the supply pipeline; the filling pipeline and the supply pipeline are respectively provided with a liquid hydrogen filling valve (17) and a liquid hydrogen supply valve (18); The front end of the ejector pipeline (21) is divided into a first branch and a second branch. The inlet of the first branch is connected to the liquid hydrogen three-way valve (8) in the high-pressure precooling pipeline (1), and the high-pressure hydrogen is used as the primary fluid of the hydrogen ejector (24); a primary flow inlet valve (22) is provided on the first branch; the inlet of the second branch is connected to the filling pipeline, and the low-pressure hydrogen from the liquid hydrogen filling tank (13) is used as the secondary fluid of the hydrogen ejector (24); a secondary flow inlet valve (23) is provided on the second branch.

2. The parallel precooling liquid hydrogen filling system according to claim 1, characterized in that: The hydrogen ejector (24) includes a primary fluid nozzle, a secondary fluid pipeline, an intake chamber, a mixing tube and a diffusion tube; the primary fluid nozzle receives high-pressure hydrogen from the high-pressure precooling pipeline (1), so that the intake chamber forms a low-pressure area; under the action of the pressure difference, the secondary fluid pipeline inhales low-pressure hydrogen from the liquid hydrogen filling tank (13), so that the low-pressure hydrogen and the high-pressure hydrogen are mixed in the mixing tube, and the flow rate is reduced in the diffusion tube before being discharged to the outside.

3. The parallel precooling liquid hydrogen filling system according to claim 1, characterized in that: The pipe valve subsystem (4) comprises a liquid hydrogen valve (5) and a liquid hydrogen metering unit (7) which are connected in sequence.

4. The parallel precooling liquid hydrogen filling system according to claim 3, characterized in that: The liquid hydrogen valve (5) is a ball valve, a stop valve, a regulating valve or a safety valve.

5. The parallel precooling liquid hydrogen filling system according to claim 3, characterized in that: The liquid hydrogen metering unit (7) adopts a mass flow meter, a liquid level meter, a flow meter, a temperature sensor or a pressure sensor.

6. The parallel precooling liquid hydrogen filling system according to claim 1, characterized in that: The pipe-valve subsystem (4) further comprises a liquid hydrogen functional component (6) arranged between the liquid hydrogen valve (5) and the liquid hydrogen metering unit (7); the liquid hydrogen functional component (6) is a pressure regulating component, a temperature regulating component or a pump component.

7. The parallel precooling liquid hydrogen filling system according to claim 1, characterized in that: The atomizing nozzle array (14) includes a plurality of rotatable atomizing nozzles, which input liquid hydrogen from the low-pressure liquid hydrogen tank (10) into the liquid hydrogen filling tank (13) at multiple angles for cooling.

8. The parallel precooling liquid hydrogen filling system according to claim 1, characterized in that: The outlet of the supply pipeline is provided with a flange (19) for connecting to external equipment.

9. The parallel precooling liquid hydrogen filling system according to claim 1, characterized in that: The high-pressure precooling pipeline (1), the low-pressure precooling pipeline (9) and the liquid hydrogen filling tank (13) are provided with insulating materials outside to prevent heat leakage; the high-pressure liquid hydrogen tank (2) and the low-pressure liquid hydrogen tank (10) use a self-pressurization method to transport liquid hydrogen.

10. A method for filling liquid hydrogen using the parallel precooling system according to any one of claims 2 to 9, characterized in that: It includes pre-cooling stage and filling stage; The precooling stage is specifically as follows: The high-pressure liquid hydrogen stop valve (3), the liquid hydrogen valve (5) in the pipe valve subsystem (4) and the primary flow inlet valve (22) are opened, and the liquid hydrogen three-way valve (8) is connected to the pipe valve subsystem (4) and the primary flow inlet valve (22); the high-pressure liquid hydrogen tank (2) enters the high-pressure liquid supply state through self-pressurization, and the high-pressure liquid hydrogen enters the pipe valve subsystem (4) through the high-pressure liquid hydrogen stop valve (3) and is converted into high-pressure hydrogen gas, thereby realizing the overall precooling of the pipe valve subsystem (4); then, the high-pressure hydrogen gas enters the primary fluid nozzle of the hydrogen ejector (24) through the liquid hydrogen three-way valve (8) and the primary flow inlet valve (22); The low-pressure liquid hydrogen stop valve (11), the liquid hydrogen atomizing valve (12), the liquid hydrogen filling valve (17) and the secondary flow inlet valve (23) are opened; the low-pressure liquid hydrogen tank (10) enters a low-pressure liquid supply state through self-pressurization, and the low-pressure liquid hydrogen enters the atomizing nozzle array (14) through the low-pressure liquid hydrogen stop valve (11) and the liquid hydrogen atomizing valve (12), and the atomized liquid hydrogen particles contact the wall of the liquid hydrogen filling tank (13) and quickly vaporize into low-pressure hydrogen; then the low-pressure hydrogen enters the secondary fluid pipeline of the hydrogen ejector (24) through the liquid hydrogen filling valve (17) and the secondary flow inlet valve (23); The hydrogen ejector (24) starts to operate, the primary fluid nozzle receives high-pressure hydrogen from the high-pressure precooling pipeline (1) and low-pressure hydrogen sucked from the secondary fluid pipeline, mixes them in the mixing tube, and then reduces the flow rate in the diffusion tube and discharges them to the outside; until the medium passing through the primary flow inlet valve (22) and the secondary flow inlet valve (23) is all liquid hydrogen, the precooling is completed, and the liquid hydrogen atomization valve (12), the primary flow inlet valve (22), and the secondary flow inlet valve (23) are closed; The filling phases are as follows: The high-pressure liquid hydrogen tank (2) is converted to a low-pressure liquid supply state by self-pressurization, and the drain valve (15) and the liquid hydrogen mixing valve (25) are opened; the liquid hydrogen three-way valve (8) is connected to the pipe valve subsystem (4) and the liquid hydrogen filling valve (17), and the liquid hydrogen medium from the high-pressure liquid hydrogen tank (2) and the liquid hydrogen medium from the low-pressure liquid hydrogen tank (10) are combined through the liquid hydrogen mixing valve (25), and then enter the liquid hydrogen filling tank (13) through the pipe valve subsystem (4), the liquid hydrogen three-way valve (8), and the liquid hydrogen filling valve (17) to perform liquid hydrogen filling; the hydrogen generated during the filling process is discharged through the drain valve (15); When the liquid hydrogen in the liquid hydrogen filling tank (13) reaches the target liquid level, the high-pressure liquid hydrogen stop valve (3), the liquid hydrogen valve (5), the low-pressure liquid hydrogen stop valve (11), the liquid hydrogen filling valve (17) and the liquid hydrogen mixing valve (25) are closed, and the drain valve (15) remains normally open, and the filling is completed.

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