System and method for quantitatively filling polluted gas source into refrigerator

Abstract

The invention relates to a system and method for quantitatively filling a refrigerator with a polluted gas source. In the system, two sides of a main pipeline are respectively connected with a third-stage air supply loop and a third-stage air inlet loop; each stage of gas supply loop is formed by sequentially connecting a gas cylinder, a pressure regulating valve and a switch valve, one of the three stages of gas inlet loops comprises a vacuum gauge, one of the three stages of gas inlet loops comprises a pressure sensor, and the other one of the three stages of gas inlet loops leads to the external environment. According to the method for quantitatively filling the refrigerator with the pollution gas sources, the refrigerator is firstly vacuumized, then one or more pollution gas sources are filled into the refrigerator under the common control of a vacuum gauge and a switching valve, and then helium is filled into the refrigerator under the common control of a pressure sensor and the switching valve; and finally, the gas is discharged from the refrigerator through the double-switch valve. Compared with the prior art, the device realizes mixed quantitative filling of one or more pollution gases, and has the advantages of simplicity, high efficiency, wide application range and high precision.

Description

Technical Field

[0001] The invention relates to the technical field of refrigerator detection, and in particular to a system and method for quantitatively charging a polluted gas source into a refrigerator. Background Art

[0002] With the development of science and technology, pollution control technology has become increasingly important in some high-end applications such as space Stirling compressors. The quantitative charging of polluted gas sources is used in the preliminary preparation of the regenerative refrigerant performance test experiment. It is of great significance to study the pollution failure mechanism of space Stirling compressors and regenerative compressors, improve the reliability of compressors and extend their service life. At present, there is no good solution in the industry to solve the problem of simple and fast quantitative charging of polluted gas sources.

[0003] Currently, when charging contaminated gas sources into refrigerators, a small volume cavity is often used for multiple injections. However, this technology has a fixed single gas filling volume, and there is no pressure gauge control in the cavity. When used in large refrigerators, multiple filling operations are required, and it is difficult to accurately control for micro refrigerators. The parts processing accuracy is high, and there are many moving parts that are prone to leakage, and there is a problem of inaccurate dead volume filling. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and to provide a system and method for quantitatively charging a polluted gas source into a refrigerator.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] According to one aspect of the present invention, there is provided a system for quantitatively charging a contaminated gas source into a refrigerator, the system comprising a three-stage air supply circuit, a three-stage air intake circuit and a main pipeline; one side of the main pipeline is connected to the three-stage air supply circuit, and the other side is connected to the three-stage air intake circuit; each stage of the air supply circuit is composed of a gas cylinder, a pressure regulating valve and a switch valve connected in sequence, the first-stage air intake circuit is composed of a fourth switch valve 7, a vacuum gauge 12, a seventh switch valve 10 and a vacuum pump 17 connected in sequence; the second-stage air intake circuit is connected to the external environment via a fifth switch valve 8; the three-stage air intake circuit is composed of a sixth switch valve 9, a pressure sensor 13 and a refrigerator cascade.

[0007] As a preferred technical solution, the refrigerator includes a compressor 18 and a cold finger 19 .

[0008] As a preferred technical solution, the main pipeline is also provided with a safety valve 11.

[0009] According to another aspect of the present invention, a method for quantitatively charging a polluted gas source into a refrigerator is provided. The method is applied to a polluted gas source quantitative charging system as described above. First, the refrigerator is evacuated to a vacuum. Then, under the control of a vacuum gauge 12 and a switch valve, one or more polluted gas sources are charged into the refrigerator. Then, under the control of a pressure sensor 13 and a switch valve, helium is charged into the refrigerator. Finally, the gas is discharged from the refrigerator through a double switch valve.

[0010] As a preferred technical solution, the specific process of charging one or more polluted gas sources into the refrigerator is:

[0011] When only the first polluted gas source needs to be charged, the second switch valve 5, the fourth switch valve 7 and the sixth switch valve 9 are opened, the second pressure regulating valve 2 is slowly rotated, and the other valves are closed. When the vacuum gauge reading reaches the preset value P1 and remains stable, the second switch valve 5, the second pressure regulating valve 2 and the fourth switch valve 7 are closed in sequence;

[0012] When only the second polluted gas source needs to be charged, the third switch valve 6, the fourth switch valve 7 and the sixth switch valve 9 are opened, the third pressure regulating valve 3 is slowly rotated, and the other valves are closed. When the reading of the vacuum gauge 12 reaches the preset value P1 and remains stable, the fourth switch valve 7, the third switch valve 6 and the third pressure regulating valve 3 are closed in sequence;

[0013] When the first and second polluted gas sources need to be mixed and charged, first open the second switch valve 5, the fourth switch valve 7 and the sixth switch valve 9, slowly rotate the second pressure regulating valve 2, close the other valves, and wait until the reading of the vacuum gauge 12 reaches the preset value P2, then close the second switch valve 5, and wait until the reading of the vacuum gauge 12 remains stable, then close the second pressure regulating valve 2, open the third switch valve 6, slowly rotate the third pressure regulating valve 3, and wait until the reading of the vacuum gauge 12 meets the preset value P1, and then close the fourth switch valve 7, the third pressure regulating valve 3 and the third switch valve 6 in sequence;

[0014] As a preferred technical solution, the mass, molar concentration, volume fraction and mass fraction of the polluted gas source charged into the refrigerator are calculated according to the reading of the vacuum gauge 12, and each quantity satisfies the following formula:

[0015]

[0016] In the formula, m0 is the mass of the polluted gas source entering the refrigerator; c is the molar concentration of the polluted gas; is the volume fraction of the polluted gas; ω is the mass fraction of the polluted gas; P0 is the reading of the vacuum gauge 12; P is the reading of the pressure sensor 13 after filling with helium; M is the molar mass of the gas; R is the gas constant; T is the Kelvin temperature of the gas; and V is the total volume of the cavity inside the refrigerator.

[0017] As a preferred technical solution, the specific process of filling the refrigerator with helium is as follows:

[0018] The fourth switch valve 7 remains closed, the first switch valve 4 and the sixth switch valve 9 are opened, the first pressure regulating valve 1 is slowly rotated, and nitrogen is filled into the compressor 18 until the reading of the pressure sensor 13 meets the preset value P and remains stable, and then the first switch valve 4, the first pressure regulating valve 1 and the sixth switch valve 9 are closed in turn.

[0019] As a preferred technical solution, the specific process of evacuating the refrigerator to a vacuum is: open the fourth switch valve 7, the sixth switch valve 9 and the seventh switch valve 10, turn on the vacuum pump 17, and after the vacuum gauge 12 reads 1.0E-6Pa, close the fourth switch valve 7, the sixth switch valve 9 and the seventh switch valve 10 to make the compressor 18 and the cold finger 19 inside a vacuum.

[0020] As a preferred technical solution, the specific process of discharging gas from the refrigerator is: open the fifth switch valve 8 and the sixth switch valve 9, and close the other valves until the pressure sensor reading is 1 bar, and then close the fifth switch valve 8 and the sixth switch valve 9.

[0021] As a preferred technical solution, during the process of charging one or more contaminated gas sources into the refrigerator, when the pressure of the charged contaminated gas source, that is, the vacuum gauge reading, exceeds a preset value, open the fourth switch valve 7 and the seventh switch valve 10, close the remaining valves, and then open the vacuum pump 17 to evacuate the pipeline. Then, close the fourth switch valve 7, the seventh switch valve 10 and the vacuum pump 17, open the sixth switch valve 9, and release the gas source to adjust the pressure.

[0022] As a preferred technical solution, the system pressure value after releasing the gas source satisfies the following formula:

[0023]

[0024] Where P R P is the target pressure indication of the vacuum gauge 12; T is the pressure in the original system; P0 is the current reading of the vacuum gauge 12; V is the total volume of the cavity inside the refrigerator; V R V is the volume of the cavity in the pipeline and refrigerator after the sixth switch valve 9; T It is the volume of the cavity in the closed pipeline surrounded by the first switch valve 4, the second switch valve 5, the third switch valve 6, the fourth switch valve 7, the fifth switch valve 8 and the sixth switch valve 9.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The system of the present invention includes a three-stage air supply circuit, a three-stage air intake circuit and a trunk pipeline; one side of the trunk pipeline is connected to the three-stage air supply circuit, and the other side is connected to the three-stage air intake circuit; each stage of the air supply circuit is composed of a gas cylinder, a pressure regulating valve and a switch valve connected in sequence, and the first-stage air intake circuit is composed of a fourth switch valve 7, a vacuum gauge 12, a seventh switch valve 10 and a vacuum pump 17 connected in sequence; the second-stage air intake circuit is connected to the external environment through the fifth switch valve 8; the third-stage air intake circuit is composed of a sixth switch valve 9, a pressure sensor 13 and a refrigerator cascade. The system has a simple structure and is easy to process, and can be widely used; the system contains multiple pressure regulating valves, switch valves, vacuum gauges and pressure sensors, so that the system can achieve efficient filling of polluted gas sources while being easy to operate, and at the same time, the system can also adjust the pressure when adding trace gas.

[0027] 2. In the method of quantitatively charging the contaminated gas source into the refrigerator of the present invention, the refrigerator is first evacuated to a vacuum, and then one or more contaminated gas sources are charged into the refrigerator under the joint control of the vacuum gauge 12 and the switch valve, and then helium is charged into the refrigerator under the joint control of the pressure sensor 13 and the switch valve; finally, the gas is discharged from the refrigerator through the double switch valve. Through this method, the pressure regulation with the highest accuracy of 10 Pa can be achieved, and the maximum charging pressure can reach the MPa level. While achieving the mixed quantitative charging of one or more gases, the working pressure span is extremely large, which ensures the accuracy of gas charging and the applicable scope of the system.

[0028] 3. In the system of the present invention, a safety valve 11 is also provided on the main pipeline to prevent accidental operation from causing excessive pressure in the pipeline, resulting in system damage, thereby improving the safety of the system.

[0029] 4. In the present invention, when the pressure of the charged contaminated gas source, i.e., the vacuum gauge reading, exceeds a preset value, the fourth switch valve 7 and the seventh switch valve 10 are opened, the remaining valves are closed, and then the vacuum pump 17 is opened to evacuate the pipeline, and then the fourth switch valve 7, the seventh switch valve 10 and the vacuum pump 17 are closed, and the sixth switch valve 9 is opened to release the gas source, etc., so as to adjust the pressure to control the charging of the gas source, thereby improving the efficiency of charging the contaminated gas source into the refrigerator, thereby improving the preliminary preparation speed of the large-scale heat recovery refrigerant performance test experiment, and improving the experimental accuracy of the refrigerant performance test experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of a system for quantitatively charging a polluted gas source into a refrigerator in the present invention;

[0031] Figure 2 This is a schematic diagram showing the comparison of the cooling capacity at temperatures of 60K and 70K when the CO2 pollution performance test is performed in the embodiment;

[0032] In the figure, 1 is the first pressure regulating valve; 2 is the second pressure regulating valve; 3 is the third pressure regulating valve; 4 is the first switch valve; 5 is the second switch valve; 6 is the third switch valve; 7 is the fourth switch valve; 8 is the fifth switch valve; 9 is the sixth switch valve; 10 is the seventh switch valve; 11 is the safety valve; 12 is the vacuum gauge; 13 is the pressure sensor; 14 is the first gas cylinder; 15 is the second gas cylinder; 16 is the third gas cylinder; 17 is the vacuum pump; 18 is the compressor; 19 is the cold finger. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0034] With the development of science and technology, pollution control technology has become increasingly important in some high-end applications such as space Stirling compressors. Quantitative charging of polluted gas sources is of great significance for studying the pollution failure mechanism of space Stirling compressors and regenerative compressors, improving the reliability of compressors and extending their service life.

[0035] Currently, the contaminated gas source is charged into the refrigerator by multiple injections in a small volume cavity. This technology has a fixed single gas filling volume, and there is no pressure gauge control in the cavity. When used in large refrigerators, multiple filling operations are required, and it is difficult to accurately control for micro refrigerators. The parts processing accuracy is high, and there are many moving parts that are prone to leakage, and there is an inaccurate dead volume filling amount.

[0036] Currently, there is no good solution in the industry to solve the problem of simple, fast and quantitative charging of polluted gas sources.

[0037] Example 1

[0038] In this embodiment, a system for quantitatively charging a polluted gas source into a refrigerator is used. Figure 1 As shown, it includes a gas cylinder, a refrigerator, an exhaust control system, a vacuum gauge 12, a pressure sensor 13 and a vacuum pump 17; the exhaust control system includes a first pressure regulating valve 1, a second pressure regulating valve 2, a third pressure regulating valve 3, a first switch valve 4, a second switch valve 5, a third switch valve 6, a fourth switch valve 7, a fifth switch valve 8, a sixth switch valve 9, a seventh switch valve 10 and a safety valve 11; the refrigerator includes a compressor 18 and a cold finger 19; the gas cylinder includes a first gas cylinder 14, a second gas cylinder 15 and a third gas cylinder 16.

[0039] In this embodiment, for the vacuuming process, the gas in the compressor 18 passes through the sixth switch valve 9, the safety valve 11, the fourth switch valve 7, the vacuum gauge 12 and the seventh switch valve 10 from the outlet of the compressor 18 in sequence, and is discharged through the vacuum pump 17. The above-mentioned connection relationship represents the vacuuming process of the system before the pollutants and refrigerant are introduced.

[0040] In this embodiment, for the charging process of the first type of polluted gas source, the polluted gas source in the second gas cylinder 15 enters the compressor 18 through the second pressure regulating valve 2, the second switch valve 5 and the sixth switch valve 9 in sequence until the reading in the vacuum gauge 12 reaches the preset value P2. The above-mentioned connection relationship represents the process of quantitatively charging the first type of polluted gas source according to the vacuum gauge reading.

[0041] In this embodiment, for the charging process of the second type of polluted gas source, the polluted gas source in the third gas cylinder 16 enters the compressor 18 through the third pressure regulating valve 3, the third switch valve 6 and the sixth switch valve 9 in sequence until the reading in the vacuum gauge 12 reaches the preset value P1. The above-mentioned connection relationship represents the process of quantitatively charging the second type of polluted gas source according to the vacuum gauge reading.

[0042] In this embodiment, for the mixed polluted gas source charging process, the polluted gas source in the second gas cylinder 15 first passes through the second pressure regulating valve 2, the second switch valve 5 and the sixth switch valve 9 in sequence to enter the compressor 18, until the reading in the vacuum gauge 12 reaches the preset value P1, and the polluted gas source in the second gas cylinder 15 is stopped. The polluted gas source in the third gas cylinder 16 is passed through the third pressure regulating valve 3, the third switch valve 6 and the sixth switch valve 9 in sequence. The above-mentioned connection relationship represents the process of quantitatively charging the mixed polluted gas source according to the vacuum gauge reading.

[0043] In this embodiment, for the process of discharging the excess charged polluted gas, only the vacuum pump 17, the fourth switch valve 7 and the seventh switch valve 10 are opened, and the gas in the pipeline is led to the vacuum pump until the pipeline is vacuumed. The above-mentioned connection relationship represents the process of discharging the excess charged gas.

[0044] In this embodiment, for the helium filling process, the helium in the first gas cylinder 14 sequentially enters the compressor 18 through the first pressure regulating valve 1, the first switch valve 4, the safety valve 11 and the sixth switch valve 9 until the reading in the pressure sensor 13 reaches a preset value. The above-mentioned communication relationship represents the process of quantitatively filling helium according to the pressure sensor reading.

[0045] In this embodiment, during the deflation process, the gas in the compressor 18 passes through the sixth switch valve 9 and the fifth switch valve 8 in sequence, and the fifth switch valve 8 is connected to the external environment. The above-mentioned connection relationship represents the gas discharge process of the system after the test is completed.

[0046] In this embodiment, when the system is working, all ten switch valves are closed in the initial state.

[0047] In this embodiment, when the system needs to be started, the seventh switch valve 10, the sixth switch valve 9 and the fourth switch valve 7 are opened, and the first switch valve 4, the second switch valve 5, the third switch valve 6, the fifth switch valve 8, the first pressure regulating valve 1, the second pressure regulating valve 2 and the third pressure regulating valve 3 are closed. The gas in the compressor 18 passes through the sixth switch valve 9, the safety valve 11, the fourth switch valve 7, the vacuum gauge 12 and the seventh switch valve 10 from the outlet of the compressor 18 in sequence, and is discharged through the vacuum pump 17. When the reading of the vacuum gauge 12 is 1.0E-6Pa, the vacuuming process is completed.

[0048] In this embodiment, when it is necessary to quantitatively charge the first type of polluted gas source and the refrigerant helium, first close the seventh switch valve 10, the first pressure regulating valve 1, the third pressure regulating valve 3, the first switch valve 4, the third switch valve 6 and the fifth switch valve 8, open the fourth switch valve 7, the second switch valve 5 and the sixth switch valve 9, slowly rotate the second pressure regulating valve 2, control the polluted gas filling rate, and realize the charging of the polluted gas source. When the reading of the vacuum gauge 12 reaches the preset value P2, quickly close the second switch valve 5. Wait for 10 to 15 minutes to achieve uniform diffusion of the polluted gas in the system. If the vacuum gauge reading remains unchanged at P2, close the second pressure regulating valve 2 and the fourth switch valve 7 in turn, open the first switch valve 4, slowly rotate the first pressure regulating valve 1, and realize the charging of helium. When the reading of the pressure sensor 13 meets the preset requirements, close the fourth switch valve 7, the first pressure regulating valve 1, the first switch valve 4 and the sixth switch valve 9. After waiting for 10 to 15 minutes to allow the first type of polluted gas source and helium to mix evenly, the process of quantitatively charging the first type of polluted gas source and mixing with helium is completed. After the experiment is completed, the sixth switch valve 9 and the fifth switch valve 8 are opened to discharge the gas in the compressor 18 into the atmosphere. When the pressure sensor reading is 1 bar, the sixth switch valve 9 and the fifth switch valve 8 are closed to complete the exhaust process.

[0049] In this embodiment, when it is necessary to quantitatively charge the second type of polluted gas source and mix it with the refrigerant helium, first close the seventh switch valve 10, the second pressure regulating valve 2, the first pressure regulating valve 1, the first switch valve 4, the second switch valve 5 and the fifth switch valve 8, open the fourth switch valve 7, the third switch valve 6 and the sixth switch valve 9, slowly rotate the third pressure regulating valve 3, control the polluted gas filling rate, and realize the charging of the polluted gas source. When the reading in the vacuum gauge 12 reaches the preset value P2, quickly close the third switch valve 6. Wait for 10 to 15 minutes to achieve uniform diffusion of the polluted gas in the system. If the vacuum gauge reading remains unchanged at P2, close the third pressure regulating valve 3 and the fourth switch valve 7 in turn, open the first switch valve 4, slowly rotate the first pressure regulating valve 1, and realize the charging of helium. When the reading of the pressure sensor 13 meets the preset requirements, close the first pressure regulating valve 1, the first switch valve 4 and the sixth switch valve 9. Wait for 10 to 15 minutes to allow the second type of polluted gas source and helium to mix evenly, and then complete the process of quantitatively charging the first type of polluted gas source and mixing with helium. After the experiment is completed, the sixth switch valve 9 and the fifth switch valve 8 are opened to discharge the gas in the compressor 18 into the atmosphere. When the pressure sensor reading is 1 bar, the sixth switch valve 9 and the fifth switch valve 8 are closed to complete the exhaust process.

[0050] In this embodiment, when it is necessary to quantitatively charge a mixed polluted gas source and refrigerant helium, first close the seventh switch valve 10, the first pressure regulating valve 1, the third pressure regulating valve 3, the first switch valve 4, the third switch valve 6 and the fifth switch valve 8, open the fourth switch valve 7, the second switch valve 5 and the sixth switch valve 9, slowly rotate the second pressure regulating valve 2, control the polluted gas filling rate, and realize the charging of the polluted gas source. When the reading of the vacuum gauge 12 reaches the preset value P1, quickly close the second switch valve 5. Wait for 10 to 15 minutes to achieve uniform diffusion of the polluted gas in the system. If the vacuum gauge reading remains unchanged at P1, open the third switch valve 6, slowly rotate the third pressure regulating valve 3, control the polluted gas filling rate, and realize the charging of the polluted gas source. When the reading of the vacuum gauge 12 meets the preset requirement P2, quickly close the third switch valve 6. Wait for 10 to 15 minutes to achieve full mixing of the two polluted gases in the system. If the vacuum gauge reading remains unchanged at P2, close the second pressure regulating valve 2, the third pressure regulating valve 3, and the fourth switch valve 7 in sequence, open the first switch valve 4, and slowly rotate the first pressure regulating valve 1 to fill helium. When the pressure sensor 13 reading meets the preset requirements, close the first pressure regulating valve 1, the first switch valve 4, and the sixth switch valve 9. Wait for 10 to 15 minutes to allow the mixed contaminated gas source and helium to mix evenly, and then complete the process of quantitatively filling the mixed contaminated gas source and mixing with helium. After the experiment is completed, open the sixth switch valve 9 and the fifth switch valve 8 to discharge the gas in the compressor 18 into the atmosphere. When the pressure sensor reading is 1 bar, close the sixth switch valve 9 and the fifth switch valve 8 to complete the exhaust process.

[0051] In this embodiment, when the amount of gas to be filled exceeds the preset value, all valves except the fourth switch valve 7 and the seventh switch valve 10 are closed, and then the vacuum pump 17 is turned on to evacuate the tube. After the vacuum is evacuated, the seventh switch valve 10, the vacuum pump 17 and the fourth switch valve 7 are closed, and the sixth switch valve 9 is opened to achieve micro-adjustment of the pressure.

[0052] Among them, the mass of polluted gas added to the refrigerator is calculated to meet the formula:

[0053]

[0054] In the formula, m0 represents the mass of the polluted gas entering the refrigerator; P0 represents the pressure value read by the vacuum gauge 12; V represents the total volume of the cavity inside the refrigerator; M represents the molar mass of the gas;

[0055] Among them, the molar concentration ratio and volume fraction of the added pollution satisfy the formula:

[0056] Where c is the molar concentration of pollutant gas; is the volume fraction of the polluted gas; P is the reading of the pressure sensor after filling with helium; P0 is the pressure value read by the vacuum gauge.

[0057] Among them, the mass fraction of added pollution satisfies the formula:

[0058]

[0059] Wherein, ω is the mass fraction of the polluted gas; M is the molar mass of the gas; V0 is the volume of the gas; V is the total volume of the cavity inside the refrigerator; P is the reading of the pressure sensor after filling with helium; P0 is the pressure value read by the vacuum gauge.

[0060] Among them, when the pressure of the incoming polluted gas exceeds the preset value by a small amount, the gas pressure in the venting pipeline after the gas is released needs to satisfy the formula:

[0061]

[0062] Where P R Indicates the target pressure indication of the vacuum gauge 12; P T represents the pressure in the original system; P0 represents the pressure value read by the vacuum gauge 12; V represents the total volume of the cavity inside the refrigerator; V R V represents the volume of the cavity in the pipeline and refrigerator after the sixth switch valve 9; T It represents the volume of the cavity in the closed pipeline surrounded by the first switch valve 4, the second switch valve 5, the third switch valve 6, the fourth switch valve 7, the fifth switch valve 8 and the sixth switch valve 9.

[0063] Example 2

[0064] In this embodiment, a method for quantitatively charging a polluted gas source into a refrigerator is applied. The method is applied to Figure 1 In the system shown, the refrigerator is first evacuated to a vacuum, and then one or more polluted gas sources are charged into the refrigerator under the control of the vacuum gauge 12 and the switch valve, and then helium is charged into the refrigerator under the control of the pressure sensor 13 and the switch valve; finally, the gas is discharged from the refrigerator through the double switch valve;

[0065] The specific process of charging one or more polluted gas sources into the refrigerator is:

[0066] When only the first polluted gas source needs to be charged, the second switch valve 5, the fourth switch valve 7 and the sixth switch valve 9 are opened, the second pressure regulating valve 2 is slowly rotated, and the other valves are closed. When the vacuum gauge reading reaches the preset value P1 and remains stable, the second switch valve 5, the second pressure regulating valve 2 and the fourth switch valve 7 are closed in sequence;

[0067] When only the second polluted gas source needs to be charged, the third switch valve 6, the fourth switch valve 7 and the sixth switch valve 9 are opened, the third pressure regulating valve 3 is slowly rotated, and the other valves are closed. When the reading of the vacuum gauge 12 reaches the preset value P1 and remains stable, the fourth switch valve 7, the third switch valve 6 and the third pressure regulating valve 3 are closed in sequence;

[0068] When the first and second polluted gas sources need to be mixed and charged, first open the second switch valve 5, the fourth switch valve 7 and the sixth switch valve 9, slowly rotate the second pressure regulating valve 2, close the other valves, and wait until the reading of the vacuum gauge 12 reaches the preset value P2, then close the second switch valve 5, and wait until the reading of the vacuum gauge 12 remains stable, then close the second pressure regulating valve 2, open the third switch valve 6, slowly rotate the third pressure regulating valve 3, and wait until the reading of the vacuum gauge 12 meets the preset value P1, and then close the fourth switch valve 7, the third pressure regulating valve 3 and the third switch valve 6 in sequence;

[0069] When helium is charged into the refrigerator, the fourth switch valve 7 remains closed, and the specific process is as follows:

[0070] Open the first switch valve 4 and the sixth switch valve 9, slowly rotate the first pressure regulating valve 1, fill nitrogen into the compressor 18, and close the first switch valve 4, the first pressure regulating valve 1 and the sixth switch valve 9 in sequence after the reading of the pressure sensor 13 meets the preset value P and remains stable.

[0071] The specific process of evacuating the refrigerator to a vacuum is as follows: open the fourth switch valve 7, the sixth switch valve 9 and the seventh switch valve 10, turn on the vacuum pump 17, and after the vacuum gauge 12 reads 1.0E-6Pa, close the fourth switch valve 7, the sixth switch valve 9 and the seventh switch valve 10 to make the compressor 18 and the cold finger 19 vacuum.

[0072] In this embodiment, the mass, molar concentration, volume fraction and mass fraction of the polluted gas source added to the refrigerator are calculated based on the reading of the vacuum gauge 12. The preset values ​​of P1 and P0 are both preset values ​​of the vacuum gauge reading. The following formulas are used to calculate the quantities, respectively:

[0073]

[0074] In the formula, m0 is the mass of the polluted gas source entering the refrigerator; c is the molar concentration of the polluted gas; is the volume fraction of the polluted gas; ω is the mass fraction of the polluted gas; P0 is the reading of the vacuum gauge 12; P is the reading of the pressure sensor 13 after filling with helium; M is the molar mass of the gas; R is the gas constant; T is the Kelvin temperature of the gas; and V is the total volume of the cavity inside the refrigerator.

[0075] The specific process of discharging the gas from the refrigerator is: open the fifth switch valve 8 and the sixth switch valve 9, and close the other valves until the pressure sensor reading is 1 bar, and then close the fifth switch valve 8 and the sixth switch valve 9.

[0076] During the process of charging one or more polluted gas sources into the refrigerator, when the pressure of the charged polluted gas source exceeds the preset value, the fourth switch valve 7 and the seventh switch valve 10 are opened, the remaining valves are closed, and the vacuum pump 17 is opened to evacuate the pipeline, and then the fourth switch valve 7, the seventh switch valve 10 and the vacuum pump 17 are closed, and the sixth switch valve 9 is opened to release the gas source to adjust the pressure. The system pressure value after releasing the gas source satisfies the following formula:

[0077]

[0078] Where P R P is the target pressure indication of the vacuum gauge 12; T is the pressure in the original system; P0 is the current reading of the vacuum gauge 12; V is the total volume of the cavity inside the refrigerator; V R V is the volume of the cavity in the pipeline and refrigerator after the sixth switch valve 9; T It is the volume of the cavity in the closed pipeline surrounded by the first switch valve 4, the second switch valve 5, the third switch valve 6, the fourth switch valve 7, the fifth switch valve 8 and the sixth switch valve 9.

[0079] In this embodiment, CO2 is selected as the polluted gas, and the method is applied to charge the polluted gas into the refrigerator.

[0080] In this embodiment, the first step of the method is: open the seventh switch valve 10, the sixth switch valve 9 and the fourth switch valve 7, close the first switch valve 4, the second switch valve 5, the third switch valve 6, the first pressure regulating valve (1), the second pressure regulating valve 2, the third pressure regulating valve 3 and the fifth switch valve 8, and when the vacuum gauge reading is 1.0E-6Pa, close the seventh switch valve 10, the sixth switch valve 9 and the fourth switch valve 7.

[0081] In this embodiment, the second step of the method is: select the source of the polluted gas source to be added; when only the polluted gas source in the second gas cylinder 15 needs to be charged, close the seventh switch valve 10, the first pressure regulating valve 1, the third pressure regulating valve 3, the first switch valve 4, the third switch valve 6 and the fifth switch valve 8, open the fourth switch valve 7, the second switch valve 5 and the sixth switch valve 9, and slowly rotate the second pressure regulating valve 2 to achieve the charging of the polluted gas source. When the reading of the vacuum gauge 12 reaches the preset value P1, close the second switch valve 5. If the reading of the vacuum gauge 12 remains unchanged at P1, close the second pressure regulating valve 2 and the fourth switch valve 7. If the reading of the vacuum gauge 12 drops, open the second switch valve 5 again until the reading of the vacuum gauge 12 reaches the preset value P1.

[0082] When only the contaminated gas source in the third gas cylinder 16 needs to be charged, close the seventh switch valve 10, the first pressure regulating valve 1, the second pressure regulating valve 2, the first switch valve 4, the second switch valve 5 and the fifth switch valve 8, open the fourth switch valve 7, the third switch valve 6 and the sixth switch valve 9, and slowly rotate the third pressure regulating valve 3 to achieve the charging of the contaminated gas source. When the reading of the vacuum gauge 12 reaches the preset value P1, close the third switch valve 6. If the reading of the vacuum gauge 12 remains unchanged at P1, close the third pressure regulating valve 3 and the fourth switch valve 7. If the reading of the vacuum gauge 12 drops, open the third switch valve 6 again until the reading of the vacuum gauge 12 reaches the preset value P1.

[0083] When both the second gas cylinder 15 and the third gas cylinder 16 need to be charged with the contaminated gas source, first close the seventh switch valve 10, the first pressure regulating valve 1, the third pressure regulating valve 3, the first switch valve 4, the third switch valve 6 and the fifth switch valve 8, open the second switch valve 5, the fourth switch valve 7 and the sixth switch valve 9, and slowly rotate the second pressure regulating valve 2 to achieve the charging of the contaminated gas source. When the reading of the vacuum gauge 12 reaches the preset value P2, close the second switch valve 5, and when the pressure remains unchanged, close the second pressure regulating valve 2. Then open the third switch valve 6, and slowly rotate the third pressure regulating valve 3 to achieve the charging of the contaminated gas source in the third gas cylinder 16. When the reading of the vacuum gauge 12 meets the preset value P1, close the third switch valve 6, and when the pressure remains unchanged, close the third pressure regulating valve 3 and the fourth switch valve 7.

[0084] In this embodiment, the third step of the method is: close the second pressure regulating valve 2, the third pressure regulating valve 3, the second switch valve 5, the third switch valve 6, the fourth switch valve 7 and the fifth switch valve 8, open the first switch valve 4, slowly rotate the first pressure regulating valve 1 to realize the filling of helium, and close the first switch valve 4, the first pressure regulating valve 1 and the sixth switch valve 9 in sequence after the reading of the pressure sensor 13 meets the preset requirements and remains stable.

[0085] In this embodiment, the fourth step of the method is: after the experiment, close the seventh switch valve 10, the first switch valve 4, the second switch valve 5, the third switch valve 6, the fourth switch valve 7, the first pressure regulating valve 1, the second pressure regulating valve 2 and the third pressure regulating valve 3, open the fifth switch valve 8 and the sixth switch valve 9, and when the pressure sensor reading is 1 bar, close the fifth switch valve 8 and the sixth switch valve 9.

[0086] In this embodiment, the method is applied to quantitatively charge the polluted gas source, control the quantitative charging of the polluted gas source, improve the preliminary preparation speed of the large-scale regenerative refrigerant performance test experiment, and improve the experimental accuracy. The impurities inside the compressor are reduced, the purity of the refrigerant is ensured, and the refrigeration performance is optimized. The refrigeration capacity comparison of the CO2 pollution performance test at 60K and 70K obtained by the method is as follows: Figure 2 As shown, at the same time, the reliability and life of the refrigeration system are improved synchronously. This is especially important for space Stirling compressors and other high-end refrigeration equipment, which have high maintenance and replacement costs.

[0087] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A system for quantitatively charging a polluted gas source into a refrigerator, characterized in that: The system comprises a three-stage air supply circuit, a three-stage air intake circuit and a trunk pipeline; one side of the trunk pipeline is connected to the three-stage air supply circuit, and the other side is connected to the three-stage air intake circuit; each stage of the air supply circuit is composed of a gas cylinder, a pressure regulating valve and a switch valve connected in sequence; the first stage of the air intake circuit is composed of a fourth switch valve (7), a vacuum gauge (12), a seventh switch valve (10) and a vacuum pump (17) connected in sequence; the second stage of the air intake circuit is connected to the external environment via a fifth switch valve (8); and the three stage of the air intake circuit is composed of a sixth switch valve (9), a pressure sensor (13) and a refrigerator cascaded.

2. A system for quantitatively charging a polluted gas source into a refrigerator according to claim 1, characterized in that: The refrigerator comprises a compressor (18) and a cold finger (19).

3. A system for quantitatively charging a polluted gas source into a refrigerator according to claim 1, characterized in that: The main pipeline is also provided with a safety valve (11).

4. A method for quantitatively charging a polluted gas source into a refrigerator, characterized in that: The method is applied to a polluted gas source quantitative charging system as described in any one of claims 1 to 3, firstly, the refrigerator is evacuated to a vacuum, then one or more polluted gas sources are charged into the refrigerator under the joint control of a vacuum gauge (12) and a switch valve, and then helium is charged into the refrigerator under the joint control of a pressure sensor (13) and a switch valve; finally, the gas is discharged from the refrigerator through a double switch valve.

5. A method for quantitatively charging a polluted gas source into a refrigerator according to claim 4, characterized in that: The specific process of charging one or more polluted gas sources into the refrigerator is: When only the first polluted gas source needs to be charged, the second switch valve (5), the fourth switch valve (7) and the sixth switch valve (9) are opened, the second pressure regulating valve (2) is slowly rotated, and the other valves are closed. When the vacuum gauge reading reaches a preset value P1 and remains stable, the second switch valve (5), the second pressure regulating valve (2) and the fourth switch valve (7) are closed in sequence; When only the second contaminated gas source needs to be charged, the third switch valve (6), the fourth switch valve (7) and the sixth switch valve (9) are opened, the third pressure regulating valve (3) is slowly rotated, and the other valves are closed. When the reading of the vacuum gauge (12) reaches a preset value P1 and remains stable, the fourth switch valve (7), the third switch valve (6) and the third pressure regulating valve (3) are closed in sequence; When the first and second polluted gas sources need to be mixed and charged, the second switch valve (5), the fourth switch valve (7) and the sixth switch valve (9) are first opened, the second pressure regulating valve (2) is slowly rotated, and the other valves are closed. After the reading of the vacuum gauge (12) reaches a preset value P2, the second switch valve (5) is closed. After the reading of the vacuum gauge (12) remains stable, the second pressure regulating valve (2) is closed again, the third switch valve (6) is opened, and the third pressure regulating valve (3) is slowly rotated. After the reading of the vacuum gauge (12) meets the preset value P1, the fourth switch valve (7), the third pressure regulating valve (3) and the third switch valve (6) are closed in sequence.

6. A method for quantitatively charging a polluted gas source into a refrigerator according to claim 5, characterized in that: The mass, molar concentration, volume fraction and mass fraction of the polluted gas source charged into the refrigerator are calculated according to the reading of the vacuum gauge (12), and each quantity satisfies the following formula: In the formula, m0 is the mass of the polluted gas source entering the refrigerator; c is the molar concentration of the polluted gas; is the volume fraction of the polluted gas; ω is the mass fraction of the polluted gas; P0 is the reading of the vacuum gauge (12); P is the reading of the pressure sensor (13) after filling with helium; M is the molar mass of the gas; R is the gas constant; T is the Kelvin temperature of the gas; and V is the total volume of the cavity inside the refrigerator.

7. A method for quantitatively charging a polluted gas source into a refrigerator according to claim 4, characterized in that: The specific process of filling the refrigerator with helium is as follows: The fourth switch valve (7) remains closed, the first switch valve (4) and the sixth switch valve (9) are opened, the first pressure regulating valve (1) is slowly rotated, and nitrogen is charged into the compressor (18) until the reading of the pressure sensor (13) meets the preset value P and remains stable, and then the first switch valve (4), the first pressure regulating valve (1) and the sixth switch valve (9) are closed in sequence.

8. A method for quantitatively charging a polluted gas source into a refrigerator according to claim 4, characterized in that: The specific process of evacuating the refrigerator to a vacuum is as follows: opening the fourth switch valve (7), the sixth switch valve (9) and the seventh switch valve (10), turning on the vacuum pump (17), and after the vacuum gauge (12) reads 1.0E-6Pa, closing the fourth switch valve (7), the sixth switch valve (9) and the seventh switch valve (10) to achieve a vacuum inside the compressor (18) and the cold finger (19).

9. A method for quantitatively charging a polluted gas source into a refrigerator according to claim 4, characterized in that: The specific process of discharging the gas from the refrigerator is: opening the fifth switch valve (8) and the sixth switch valve (9), and closing the other valves until the pressure sensor reading is 1 bar, and then closing the fifth switch valve (8) and the sixth switch valve (9).

10. A method for quantitatively charging a polluted gas source into a refrigerator according to claim 4, characterized in that: During the process of charging one or more contaminated gas sources into the refrigerator, when the pressure of the charged contaminated gas source, i.e., the vacuum gauge reading, exceeds a preset value, the fourth switch valve (7) and the seventh switch valve (10) are opened, the remaining valves are closed, and then the vacuum pump (17) is opened to evacuate the pipeline, and then the fourth switch valve (7), the seventh switch valve (10) and the vacuum pump (17) are closed, and the sixth switch valve (9) is opened to release the gas source to adjust the pressure. The system pressure value after releasing the gas source satisfies the following formula: Where P R P is the target pressure indication of the vacuum gauge (12); T is the pressure in the original system; P0 is the current reading of the vacuum gauge (12); V is the total volume of the cavity inside the refrigerator; V R V is the volume of the cavity in the pipeline and refrigerator after the sixth switch valve (9); T It is the volume of the cavity in the closed pipeline surrounded by the first switch valve (4), the second switch valve (5), the third switch valve (6), the fourth switch valve (7), the fifth switch valve (8) and the sixth switch valve (9).

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