Filling system for cryogenic propellant

Abstract

The utility model relates to the technical field of low-temperature propellant filling, and particularly discloses a low-temperature propellant filling system which comprises a filling pipeline, and the tail end of the filling pipeline is installed at a storage tank filling port. The filling pipeline is communicated with the low-temperature storage tank through the storage tank filling port, and a first valve is mounted on the filling pipeline; the drainage assembly comprises a drainage pipe, the initial end of the drainage pipe is installed between the first valve of the filling pipeline and the storage tank filling port, a collecting pipe is arranged at the tail end of the drainage pipe, and a second valve is arranged on the drainage pipe; the discharging assembly is additionally arranged on the filling pipeline, redundant low-temperature propellants in the low-temperature storage box are matched, in the equipment parking process, the redundant low-temperature propellants in the redundant part in the low-temperature storage box are discharged through drainage, bubbles generated by heat leakage are discharged out of a pipeline system in time, the situation that bubbles are gathered to form a bubbling spring is prevented, and generation of the bubbling spring is eradicated.

Description

Technical Field

[0001] This utility model relates to the field of cryogenic propellant loading technology, and specifically to a cryogenic propellant loading system. Background Technology

[0002] In vertical pipelines with a high aspect ratio, such as those used for equipment requiring cryogenic propellant, the cryogenic propellant, operating under low temperature and low heat flux conditions, will evaporate and generate bubbles due to pipeline leakage. As the evaporation rate gradually increases, the static pressure within the vertical pipeline decreases, accelerating bubble formation and rapidly creating a large number of bubbles that block the pipeline. After accumulating for a period of time, these large bubbles abruptly "carry" the liquid column above them out of the pipeline. The liquid column is then displaced by the released vapor and eventually collapses. Subsequently, the liquid above the vertical pipeline refills, causing water hammer and pressure fluctuations, and the system returns to a sub-heated boiling condition. This phenomenon of repeated ejection of gas or liquid flow is known as the fountain phenomenon. The root cause of the fountain phenomenon is heat leakage in the cryogenic pipeline, which develops in vertical pipelines with a high aspect ratio. To prevent the bubbles generated by the fountain phenomenon from affecting other areas and equipment, it is necessary to address this issue.

[0003] The existing liquid oxygen pressurization and delivery systems of the US Titan I and Saturn V employ a helium injection purging scheme. After helium purging at the oxygen connector, the flow rate is approximately 0.566 m / s. The mechanism is as follows: during purging, the oxygen partial pressure in the nitrogen bubbles is 0, creating a vapor pressure difference with the liquid oxygen, causing hot oxygen to evaporate and diffuse. Helium, on the other hand, provides a cooling effect, absorbing the heat of vaporization and suppressing the source of bubbling. Disadvantages include: the discharge of purging gas from the pipeline and tank, and the disturbance of the liquid by the vapor, leading to flow uncertainty; helium is redundant in the oxygen system; and the large amount of helium used is wasteful.

[0004] In summary, a novel solution is urgently needed to address the gushing phenomenon in cryogenic propellant loading systems. Utility Model Content

[0005] To address the shortcomings of existing technologies, this invention provides a cryogenic propellant loading system.

[0006] A cryogenic propellant refueling system includes a refueling pipeline, the end of which is installed at the refueling port of a storage tank; the refueling pipeline is connected to a cryogenic storage tank through the refueling port, and a first valve is installed on the refueling pipeline;

[0007] A drainage assembly, comprising a drainage pipe, the beginning of which is installed between a first valve in the filling pipeline and the filling port of the storage tank, the end of which is provided with a collecting pipe, and a second valve on the drainage pipe;

[0008] The cryogenic tank is equipped with redundancy based on the required volume of cryogenic propellant. The cryogenic tank is filled and the redundant portion is filled through the filling pipeline.

[0009] The drain pipe has a diameter of DN40 and is equipped with a temperature sensor and a pressure sensor.

[0010] The drain pipe is also equipped with a third valve, which is a regulating valve, and the second valve is a shut-off valve.

[0011] The filling pipeline is a DN150 pipeline, and the manifold is a DN350 pipeline.

[0012] An improved method for a cryogenic propellant refueling system includes a refueling pipeline, the end of which is installed at the refueling port of a storage tank, the refueling pipeline being connected to a cryogenic storage tank through the refueling port, and a first valve being installed on the refueling pipeline;

[0013] The filling pipeline is also equipped with a fourth valve, which is located on the side of the first valve away from the cryogenic storage tank. A discharge pipeline is provided between the first valve and the second valve. The discharge pipeline is connected to a manifold and is equipped with a fifth valve.

[0014] A drain pipe is installed between the first valve and the tank filling port, and a second valve is provided on the drain pipe.

[0015] The filling and discharging pipelines are DN150, the collecting pipe is DN350, the drain pipe is DN40, and a temperature sensor and a pressure sensor are installed on the drain pipe.

[0016] The drain pipe is also equipped with a third valve, which is a regulating valve, and the second valve is a shut-off valve.

[0017] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0018] 1. This utility model adds a discharge component to the filling pipeline, which, together with the excess cryogenic propellant in the cryogenic storage tank, allows the excess cryogenic propellant in the cryogenic storage tank to be discharged during equipment downtime. This enables the bubbles generated by heat leakage to be discharged from the pipeline system in a timely manner. At the same time, the discharge of bubbles with the cryogenic propellant can reduce the temperature at the heat leakage point in the pipeline, delay the generation of new bubbles, prevent the accumulation of bubbles to form fountains, and thus eliminate the generation of fountains.

[0019] 2. This utility model addresses the problem that existing filling systems cannot eliminate bubbles generated by heat leakage, which may lead to bubble aggregation and the formation of springs. Following the principle of minimal modification, a DN40 drain pipe is installed between the first valve and the filling port of the storage tank to allow the bubbles generated by heat leakage to be discharged from the pipeline system in a timely manner, preventing them from aggregating and forming springs. This eliminates pressure fluctuations caused by springs and prevents the cryogenic storage tank from depressurizing due to excessively rapid discharge. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0021] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present utility model;

[0022] Figure 2 This is a structural schematic diagram of Embodiment 2 of the present invention.

[0023] In the diagram: 1. Filling pipeline; 2. First valve; 3. Drain pipe; 4. Second valve; 5. Third valve; 6. Combining pipe; 7. Fourth valve; 8. Discharge pipeline; 9. Fifth valve; 10. Cryogenic storage tank. Detailed Implementation

[0024] The following drawings will disclose several embodiments of this utility model. For clarity, many physical details will be described in the following description. However, it should be understood that these physical details should not be used to limit this utility model. That is, in some embodiments of this utility model, these physical details are not essential. In addition, for the sake of simplicity, some conventional structures and components will be shown in the drawings in a simple schematic manner.

[0025] Furthermore, in this utility model, the use of terms such as "first" and "second" is for descriptive purposes only and does not specifically refer to any order or sequence, nor is it intended to limit the utility model. They are merely used to distinguish components or operations described with the same technical terms and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but only if they are feasible for those skilled in the art. If a combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0026] Example 1

[0027] Please see Figure 1 The present invention discloses a cryogenic propellant refueling system, which is a newly constructed cryogenic propellant refueling system. It includes a refueling pipeline 1, the end of which is installed at the refueling port of the storage tank. The refueling pipeline 1 is connected to the cryogenic storage tank 10 through the refueling port. A first valve 2 is installed on the refueling pipeline 1. The system also includes a drainage assembly, which includes a drainage pipe 3. The beginning of the drainage pipe 3 is installed between the first valve 2 of the refueling pipeline 1 and the refueling port of the storage tank. A collecting pipe 6 is provided at the end of the drainage pipe 3. A second valve 4 is provided on the drainage pipe 3.

[0028] The cryogenic storage tank 10 is equipped with redundancy based on the volume of cryogenic propellant required for use. The cryogenic storage tank 10 is filled with the redundant portion through the filling pipeline 1.

[0029] The drain pipe 3 has a diameter of DN40 and is equipped with a temperature sensor and a pressure sensor.

[0030] The drain pipe 3 is also equipped with a third valve 5, which is a regulating valve. The first valve 2 and the second valve 4 are both shut-off valves. By closing the third valve 5, opening the second valve 4, and then adjusting the opening of the third valve 5 in stages, the filling pipeline 1 can be effectively pre-cooled at a small flow rate.

[0031] The filling pipeline 1 is a DN150 pipeline, and the manifold 6 is a DN350 pipeline.

[0032] When using this utility model:

[0033] By periodically or continuously discharging the excess cryogenic propellant in the cryogenic tank 10, the bubbles generated by heat leakage are promptly discharged from the pipeline system. At the same time, the discharge of bubbles with the cryogenic propellant can reduce the temperature at the heat leakage point in the pipeline, delay the generation of new bubbles, prevent them from accumulating and forming fountains, and thus eliminate the generation of fountains.

[0034] When the cryogenic tank 10 is in the automatic cryogenic propellant loading or pre-launch cryogenic propellant replenishment state, the cryogenic propellant in the loading pipeline 1 is in a flowing state, which will not lead to heat leakage and accumulation, and thus will not cause a fountain.

[0035] Once the required cryogenic propellant has been added to the cryogenic storage tank 10, more cryogenic propellant is added to fill the excess portion of the tank, ensuring that there is sufficient propellant to discharge air bubbles. Then, the first valve 2 on the filling line 1 is closed. With the first valve 2 closed, the cryogenic propellant remains stagnant, and heat leakage will gradually occur. To prevent the air bubbles generated by heat leakage from accumulating and forming a spring, the second valve 4 in the drain pipe 3 is opened, causing the cryogenic propellant in the cryogenic storage tank 10 to flow in the reverse direction. This drainage assembly installed on the filling line 1 effectively prevents piping.

[0036] Since the generation and aggregation of bubbles require a certain amount of time, the opening and closing time of the second valve 4 located on the drain pipe 3 can be determined according to the heat leakage situation.

[0037] Based on the equipment downtime, the redundant volume of the cryogenic storage tank 10, and the discharge flow rate of the drainage components, a certain amount of additional propellant needs to be added beyond the normal usage to meet the cryogenic propellant discharge requirements during the equipment downtime. During actual discharge, if the reserved cryogenic propellant reserve does not match the maximum actual discharge rate of the drainage components, the valve opening can be adjusted in real time according to the discharge rate. When the discharge flow rate is too high, and it is estimated that the remaining cryogenic propellant will be significantly insufficient after continuous discharge, the opening of the third valve 5 should be reduced to decrease the discharge flow rate. When the discharge flow rate is too low, and it is estimated that the remaining cryogenic propellant will be significantly large after continuous discharge, the opening of the third valve 5 should be increased to increase the discharge flow rate.

[0038] Discharge method: Close the third valve 5 and open the second valve 4; adjust the opening of the third valve 5 in stages, first pre-cool the injection pipeline 1 with a small flow rate, and after pre-cooling, continue to adjust the opening of the third valve 5 until the discharge flow rate requirement is met.

[0039] Discharge mode: Continuous discharge is possible, with a pre-set discharge rate based on the cryogenic propellant capacity of the redundant portion in cryogenic tank 10. Since the actual discharge flow rate requires a certain time period from heat leakage to fountain formation, intermittent discharge is also possible. The discharge interval depends on the amount of heat leakage and the remaining amount of cryogenic propellant.

[0040] Example 2:

[0041] Please see Figure 2 An improved method for a cryogenic propellant refueling system includes a refueling pipeline 1, the end of which is installed at the refueling port of a storage tank. The refueling pipeline 1 is connected to a cryogenic storage tank 10 through the refueling port, and a first valve 2 is installed on the refueling pipeline 1.

[0042] A fourth valve 7 is also installed on the filling pipeline 1. The fourth valve 7 is located on the side of the first valve 2 away from the cryogenic storage tank 10. A discharge pipeline 8 is provided between the first valve 2 and the second valve 4. The discharge pipeline 8 is connected to the manifold 6 and a fifth valve 9 is provided on the discharge pipeline 8.

[0043] The cryogenic storage tank 10 is equipped with redundancy according to the volume of cryogenic propellant required for use. The cryogenic storage tank 10 is filled and the redundant part is filled through the filling pipeline 1.

[0044] A drain pipe 3 is installed between the first valve 2 and the tank filling port, and a second valve 4 is installed on the drain pipe 3;

[0045] The filling pipeline 1 and the discharge pipeline 8 are DN150 pipelines, the manifold 6 is DN350, the discharge pipeline 3 is DN40, and a temperature sensor and a pressure sensor are installed on the discharge pipeline 3.

[0046] The drain pipe 3 is also equipped with a third valve 5, which is a regulating valve, and the first, second, fourth and fifth valves 9 are all shut-off valves;

[0047] In this embodiment:

[0048] As an improvement to the cryogenic propellant loading system, this method addresses the problem that existing loading systems cannot eliminate bubbles generated by heat leakage, which may lead to bubble aggregation and the formation of fountains. Following the principle of minimal modification, a DN40 drain pipe 3 can be installed between the first valve 2 and the tank loading port. This drain pipe 3 connects to a third valve 5 (acting as a regulating valve) and a second valve 4 (acting as a shut-off valve). The DN40 drain pipe 3 allows for periodic or continuous discharge of the cryogenic propellant, ensuring that bubbles generated by heat leakage are promptly discharged from the pipeline system, preventing their aggregation and the formation of fountains, thereby eliminating pressure fluctuations caused by fountains.

[0049] It should be noted that, in order to prevent the generation of springs by discharging cryogenic propellant through the drain pipe 3, it is preferable that the internal cryogenic storage tank 10 of the equipment to be used for refueling has redundant space.

[0050] It should be noted that in the existing pipeline, the discharge pipeline 8 has the function of reverse discharge of cryogenic propellant. However, since its main function is to be used for venting the filling pipeline 1 after the cryogenic storage tank 10 is filled and the filling and drain valves on the equipment are closed, the discharge pipeline diameter 8 needs to be compatible with the filling pipeline diameter 1 to achieve rapid discharge. In the research process, if the discharge pipeline 8, which is a DN150 pipeline, is used directly for reverse discharge of cryogenic propellant, the excessively large pipe diameter will cause the discharge to be too fast and the storage tank to lose pressure. Therefore, the cryogenic propellant filling system needs to be improved.

[0051] The above are merely embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made to the spirit and principles of this utility model should be included within the scope of the claims of this utility model.

Claims

1. A cryogenic propellant loading system, characterized in that, include: There is a filling pipeline (1), the end of which is installed at the filling port of the storage tank; the filling pipeline (1) is connected to the cryogenic storage tank (10) through the filling port of the storage tank, and a first valve (2) is installed on the filling pipeline (1); The drainage assembly includes a drainage pipe (3), the beginning of which is installed between the first valve (2) of the filling pipeline (1) and the filling port of the storage tank, the end of which is provided with a collecting pipe (6), and the drainage pipe (3) is provided with a second valve (4). The cryogenic tank (10) is redundant according to the volume of cryogenic propellant required for use, and the cryogenic tank (10) is filled and the redundant part is filled through the filling pipeline (1).

2. The cryogenic propellant loading system according to claim 1, characterized in that: The drain pipe (3) has a diameter of DN40 and is equipped with a temperature sensor and a pressure sensor.

3. The cryogenic propellant loading system according to claim 1, characterized in that: The drain pipe (3) is also equipped with a third valve (5) which is a regulating valve, and the second valve (4) is a shut-off valve.

4. The cryogenic propellant loading system according to claim 1, characterized in that: The filling pipeline (1) is a DN150 pipeline, and the collecting pipe (6) is a DN350 pipeline.

5. A cryogenic propellant loading system according to any one of claims 1-4, characterized in that: The filling pipeline (1) is also equipped with a fourth valve (7), which is located on the side of the first valve (2) away from the cryogenic storage tank (10). Between the first valve (2) and the second valve (4), there is a discharge pipeline (8) connected to the manifold (6), and a fifth valve (9) is provided on the discharge pipeline (8).

Images