A pressure stabilizing device and jet method based on supercritical carbon dioxide high-pressure jet.

Abstract

This invention belongs to the field of high-pressure fluid jet control technology, and particularly relates to a pressure stabilizing device and jetting method based on supercritical carbon dioxide high-pressure jet. It includes a carbon dioxide storage cylinder, a cold bath connected to the outlet of the carbon dioxide storage cylinder, a cold bath outlet connected to a liquid carbon dioxide storage tank, a storage tank outlet connected to a booster pump inlet, a booster pump outlet connected to a hot bath, and a hot bath outlet connected to a jet pressure stabilizer. One end of the jet pressure stabilizer has a nitrogen inlet pipeline, and the other end has a high-pressure supercritical carbon dioxide outlet pipeline. The high-pressure supercritical carbon dioxide outlet pipeline is connected to the jetting system. The jetting system also includes an impact force characteristic testing component. This invention solves the problems of low operating efficiency, poor cutting effect, and difficulty in accurately controlling the fluid jetting process caused by fluid pressure fluctuations and sudden drops in engineering. This pressure stabilization method is simple, easy to implement, and convenient to control, and has broad application prospects.

Description

Technical Field

[0001] This invention belongs to the field of high-pressure fluid jet control technology, and particularly relates to a pressure stabilizing device and jet method based on supercritical carbon dioxide high-pressure jet. Background Technology

[0002] Jet jets are classified into gas jets and liquid jets based on the medium. Both types of jets are widely used. However, because liquids are much less compressible than gases, practical engineering applications often encounter scenarios with large pressure fluctuations and high control difficulty, such as plunger pump pressurization fluctuations and high-pressure liquid tank injection. This leads to low operating efficiency, poor jet cutting accuracy, and difficulty in controlling operating parameters. Therefore, stable pressure output of high-pressure liquids is a prerequisite for optimizing operating parameters and improving operating efficiency in high-pressure fluid jetting operations.

[0003] To stabilize the output pressure of high-pressure fluids, patent CN201910801264.X discloses a "pressure stabilization system and method for a high-pressure water jet system mounted on a TBM," which uses a host computer to control the pressure stabilization mechanism to adjust the water pressure in the accumulator for pressure stabilization. However, this device has a complex control process, high cost, and is difficult to promote. This invention, through research on pressure stabilization testing in the testing phase and analysis of the fragmentation state of the sample after jet injection, adjusts the jet pressure of the entire system. This allows the jet vessel to be removed, and the nozzle to be directly placed in the operating environment for jet cutting of coal seams. This simple, reliable, and low-cost device achieves fluid pressure stabilization while possessing a wide operating pressure range and different pressure increase / decrease methods, which is key to precise control of high-pressure fluid jetting. Furthermore, this device provides substantial guidance for research on practical engineering applications. Summary of the Invention

[0004] The purpose of this invention is to provide a pressure stabilizing device and jetting method based on supercritical carbon dioxide high-pressure jetting. This device is applicable to the field of jetting and can achieve stable jetting pressure output.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A supercritical carbon dioxide high-pressure jet pressure stabilization device includes a carbon dioxide storage cylinder, a cold bath connected to the outlet of the carbon dioxide storage cylinder, a cold bath outlet connected to a liquid carbon dioxide storage tank, a storage tank outlet connected to a booster pump inlet, a booster pump outlet connected to a hot bath, and a hot bath outlet connected to a jet pressure stabilizer. One end of the jet pressure stabilizer is equipped with a nitrogen inlet pipeline, and the other end is equipped with a high-pressure supercritical carbon dioxide outlet pipeline. The high-pressure supercritical carbon dioxide outlet pipeline is connected to a jet system. The jet system includes a nozzle and an impact force characteristic testing component. The impact force characteristic testing component includes an impact force characteristic testing vessel and a jet vessel. Using the impact force characteristic testing vessel and the jet vessel together allows for analysis of the impact force characteristic test vessel's effect on the fragmentation state of the sample after jet injection. Adjusting the jet pressure of the entire system allows the jet vessel to be removed, and the nozzle can be directly placed in the operating environment for jet cutting of coal seams.

[0007] Furthermore, both the cold bath and the hot bath are equipped with a loop pipe for the flow of carbon dioxide. Outside the loop pipe is a temperature-regulating medium jacketed cavity. The jacketed cavity of the cold bath contains coolant, which is supplied by an air-cooled compressor. The temperature-regulating medium of the hot bath is high-temperature silicone oil.

[0008] Furthermore, the jet voltage regulator includes a horizontally placed T-shaped sealed container, which consists of two concentrically connected cylindrical containers. The inner diameter of the left container is larger than that of the right container. Each container has a vertical sealing piston connected by a spring. The left container is a nitrogen storage chamber connected to a nitrogen inlet pipeline, while the right container is a high-pressure supercritical carbon dioxide storage chamber connected to a high-pressure supercritical carbon dioxide inlet. A limiter and an electric spark generator are located at the left end of the left container. The limiter is inside the left container, and the electric spark generator is embedded in the wall of the left container and controlled by an external high-frequency power supply. The high-frequency power supply generates a high-frequency alternating electric field with electrodes, creating breakdown conditions to produce plasma, thereby releasing a high-temperature, high-pressure electric spark. The operation of the electric spark generator rapidly heats the nitrogen in the nitrogen storage chamber, causing the nitrogen pressure to rise rapidly to the required pressure. The limit switch prevents the sealed piston in the nitrogen storage chamber from touching the spark generator, thus preventing damage to the equipment. A sealing piston blocking switch is provided on the inner wall of the leftmost end of the right tank.

[0009] Furthermore, the nitrogen inlet pipeline is supplied with nitrogen from a nitrogen storage tank, which is connected to the nitrogen inlet pipeline via a gas booster pump. The nitrogen storage tank is equipped with a cooling component, a nitrogen replenishment pipeline, and an automatic alarm. The cooling component cools the recovered high-temperature nitrogen using coolant. The nitrogen replenishment pipeline replenishes the nitrogen in the storage tank. The automatic alarm sounds when the nitrogen in the storage tank is insufficient, reminding the operator to replenish the nitrogen in time. The nitrogen storage chamber is connected to the nitrogen storage tank via a gas booster pump and pipeline. When the pressure in the nitrogen storage chamber is too high, excess nitrogen is transferred to the nitrogen storage tank; when the pressure is too low, nitrogen in the storage tank is transferred to the storage chamber.

[0010] Furthermore, the nitrogen storage chamber, the high-pressure supercritical carbon dioxide storage chamber, the cold bath box, the hot bath box, and the nitrogen storage tank are all equipped with thermometers and pressure gauges.

[0011] Furthermore, the impact force characteristic testing vessel includes a nozzle positioned at the center of the top of the vessel and an I-Scan pressure sensor located at the nozzle outlet. The I-Scan pressure sensor is connected to an I-Scan signal receiver and an information processing unit via an electrical signal. High-pressure supercritical carbon dioxide jets impact the target through the nozzle, and the signal is transmitted from the I-Scan pressure sensor to the I-Scan signal receiver. After the jet impact ends, information processing is performed to obtain a scientifically accurate jet impact pressure fluctuation. The operating frequency of the jet regulator is adjusted based on the pressure fluctuation results to meet the pressure fluctuation requirements.

[0012] Furthermore, the jet vessel is equipped with a cylindrical sleeve inside, which is used to fix the sample. The center of the sleeve is positioned directly opposite the nozzle, thereby ensuring that the impact position remains unchanged when the jet impacts the sample target. The supercritical carbon dioxide impacts the sample, and the reaction and breakage of the sample occur within the jet vessel, ensuring a continuous and stable jet flow.

[0013] A jetting method based on a supercritical carbon dioxide high-pressure jet stabilizing device includes the following steps:

[0014] (1) Calculate and determine the required fluid pressure. The operator checks the airtightness of the pipeline and interface. After confirming that there are no errors, open the pipeline valve, close the jet system valve, and set the target operating pressure and temperature of the pressure gauge and thermometer. (2) Connect the impact force characteristic test vessel, adjust the target distance according to the test requirements, and seal it.

[0015] (3) Place the sample into the sleeve in the jet reactor, adjust the sample target distance according to the test requirements, and tighten the bolts of the jet reactor to seal it.

[0016] (4) Open the valve of the carbon dioxide cylinder to allow carbon dioxide to flow into the cold bath box. After the temperature inside the cold bath box reaches the set temperature, store the liquid carbon dioxide in the storage tank.

[0017] (5) Turn on the plunger-type booster pump and use the booster pump to increase the pressure of liquid carbon dioxide to the required pressure. The high-pressure carbon dioxide flows into the hot bath and is heated to the set temperature in the hot bath. The heated high-pressure carbon dioxide reaches the supercritical state and flows into the jet regulator and is stored in the jet regulator.

[0018] (6) After the high-pressure supercritical carbon dioxide injection is completed, open the nitrogen replenishment pipeline to fill the nitrogen storage tank with nitrogen, and at the same time turn on the gas booster pump to let the nitrogen enter the nitrogen storage chamber. After the target pressure is reached by the nitrogen storage chamber pressure gauge, the high-pressure nitrogen injection will automatically stop.

[0019] (7) When the pressure in the storage tank is lower than the target value, the automatic alarm will sound and the operator will replenish nitrogen in time through the nitrogen replenishment pipeline to prevent the storage tank from collapsing.

[0020] (8) When the pressure in the gas storage chamber is lower than the target value, nitrogen is added by a gas booster pump. When the pressure in the gas storage chamber is higher than the target value, excess nitrogen in the gas storage chamber is automatically discharged by a gas booster pump to prevent the gas storage chamber from overpressure.

[0021] (9) After the setup is completed, the operator turns on the jet regulator switch to start the jet system. At this time, the electric spark generator will turn on automatically to heat the nitrogen gas, causing the nitrogen gas to expand and the pressure to rise. During the process of fluid discharge, the two pistons move to the right to keep the pressure balanced.

[0022] (10) High-pressure supercritical carbon dioxide fluid reaches the impact target of the impact force characteristic test vessel through the pipeline to conduct jet impact pressure distribution and fluctuation test. The jet passes through the I-Scan pressure sensor to transmit the signal to the I-Scan signal receiver and perform information processing. The working frequency of the electric spark generator is adjusted according to the test result feedback data.

[0023] (11) High-pressure supercritical carbon dioxide fluid reaches the jet reactor through pipeline to impact the sample and cause reaction, breakage and other related operations;

[0024] (12) Open the jet vessel, take out the sample after jetting, and complete the relevant high-pressure supercritical carbon dioxide jetting operation.

[0025] (13) Place the new sample into the sleeve of the jet vessel, adjust the target distance as required and close the jet vessel, tighten the bolts on the jet vessel to seal it, and repeat steps (2)-(12) to complete the test.

[0026] (14) After the test is completed, based on the analysis of the test results, in the actual application of the project, the jet vessel in the device is removed and the nozzle is directly aimed at the coal seam that needs to be cut.

[0027] The advantages of this invention are:

[0028] 1. The device of this invention first conducts pressure stabilization tests during the testing phase. By analyzing the fragmentation state of the sample after jet injection, the jet pressure of the entire system is adjusted so that the jet vessel can be removed and the nozzle can be directly placed in the operating environment for jet cutting of coal seams. This device achieves fluid pressure stabilization through a simple, reliable, and low-cost device. It also has a wide working pressure range and different pressure increase-decrease methods, which is the key to precise control of high-pressure fluid injection. At the same time, this device provides substantial guidance for research on practical engineering applications.

[0029] 2. This device uses nitrogen, which is highly compressible, stable, and widely available, as the primary pressure buffer medium, and springs as the secondary pressure buffer medium. This dual pressure-stabilizing structure greatly improves the stability of the output pressure of the high-pressure, low-compressibility fluid.

[0030] 3. This device uses a "T"-shaped sealed tank, which increases the capacity of the pressure-stabilizing fluid while reducing the size of the device through a variable cross-section method. In actual use, the sealing piston area ratio can be adjusted according to the pressure range. It has a strong stabilizing effect on pressure fluctuations caused by the pressurization of the plunger pump and pressure drops caused by the release of the high-pressure storage tank. It has a wide range of applications.

[0031] 4. This device uses a high-energy electric arc to rapidly heat nitrogen gas and increase its pressure, achieving secondary pressure boosting of the jet medium based on the primary pressure boosting of the plunger pump. This breaks through the limitation of traditional high-pressure plunger pump power on jet pressure, meets the requirements of ultra-high pressure jet operation under special conditions, and has low equipment requirements, a wide adjustable working pressure range, simple and reliable structure, and strong prospects for promotion. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of the supercritical carbon dioxide high-pressure jet stabilizing device during testing.

[0033] Figure 2 This is a schematic diagram of the jet voltage regulator structure in this invention.

[0034] Figure 3 This is a schematic diagram of the electric spark generator principle in this invention.

[0035] Figure 4 This is a schematic diagram of the jet system in this invention. Detailed Implementation

[0036] As shown in the figure, a supercritical carbon dioxide high-pressure jet pressure stabilization device includes a carbon dioxide storage cylinder 1, a cold bath box 2 connected to the outlet of the carbon dioxide storage cylinder 1, an outlet of the cold bath box 2 connected to a liquid carbon dioxide storage tank 3, an outlet of the storage tank connected to the inlet of a booster pump 4, an outlet of the booster pump connected to a hot bath box 5, an outlet of the hot bath box connected to a jet pressure stabilizer 6, a nitrogen inlet pipeline at one end of the jet pressure stabilizer, a high-pressure supercritical carbon dioxide outlet pipeline at the other end, and a jet system. The jet system includes a nozzle 7 and an impact force characteristic testing component; the impact force characteristic testing component includes an impact force characteristic testing vessel 8 and a jet vessel 9. The impact force characteristic test vessel and the jet vessel are used together to analyze the impact of jet pressure on the fragmentation state of the sample after jet injection. By adjusting the jet pressure of the entire system, the jet vessel can be removed and the nozzle can be directly placed in the operating environment for jet cutting of coal seams. Both the cold bath and the hot bath are equipped with loop pipes 10 for carbon dioxide circulation. Outside the loop pipes is a temperature-regulating medium jacket cavity. The jacket cavity of the cold bath contains coolant, which is supplied by an air-cooled compressor 11. The temperature-regulating medium of the hot bath is high-temperature silicone oil. The air-cooled compressor cools the coolant in the cold bath through refrigeration. The coolant in the cold bath circulates carbon dioxide through the loop pipes in the cold bath. After cooling to a liquid state, the booster pump pressurizes the cooled liquid carbon dioxide to the required pressure and introduces it into the hot bath. Inside the hot bath, high-temperature silicone oil pressurizes the high-pressure liquid carbon dioxide in its loop pipe, thus completing the supercritical carbon dioxide preparation. The jet pressure regulator 6 includes a horizontally placed T-shaped sealed tank, which consists of two concentrically connected cylindrical tanks. The inner diameter of the left tank is larger than that of the right tank. Both the left and right tanks contain a vertical sealing piston 12, connected by a spring 13. The left tank is a nitrogen storage chamber 14 connected to the nitrogen inlet pipeline, and the right tank is a high-pressure supercritical carbon dioxide storage chamber 15. Connected to the high-pressure supercritical carbon dioxide inlet, the left end of the left tank is equipped with a limiter 16 and an electric spark generator 17. The limiter is located inside the left tank, and the electric spark generator is embedded in the wall of the left tank. It is controlled by an external high-frequency power supply. The high-frequency power supply generates a high-frequency alternating electric field with the electrodes, forming a breakdown condition to generate plasma, thereby releasing a high-temperature and high-pressure electric spark. The operation of the electric spark generator can rapidly heat the nitrogen in the nitrogen storage chamber, causing the nitrogen pressure to rise rapidly to reach the required pressure. The limiter can prevent the sealed piston in the nitrogen storage chamber from touching the electric spark generator to prevent damage to the equipment. The inner wall of the leftmost end of the right tank is equipped with a sealing piston blocking switch 25.The nitrogen inlet pipeline is supplied with nitrogen from nitrogen storage tank 18, which is connected to the nitrogen inlet pipeline via a gas booster pump. The nitrogen storage tank is equipped with a cooling component, a nitrogen replenishment pipeline 19, and an automatic alarm 20. The cooling component cools the recovered high-temperature nitrogen using coolant. The nitrogen replenishment pipeline replenishes nitrogen in the storage tank. The automatic alarm sounds when nitrogen in the storage tank is insufficient, reminding operators to replenish nitrogen promptly. The nitrogen storage chamber is connected to the nitrogen storage tank via a gas booster pump and pipeline. When the pressure in the nitrogen storage chamber is too high, excess nitrogen is transferred to the nitrogen storage tank; when the pressure is too low, nitrogen in the storage tank is transferred to the storage chamber. The nitrogen storage chamber and high-pressure... The supercritical carbon dioxide storage chamber, cold bath, hot bath, and nitrogen storage tank are all equipped with thermometers and pressure gauges. The impact force characteristic testing vessel includes a nozzle 7 located at the center of the top of the vessel and an I-Scan pressure sensor 21 located at the nozzle outlet. The I-Scan pressure sensor is connected to an I-Scan signal receiver 22 and an information processing unit 23 via electrical signals. High-pressure supercritical carbon dioxide jets impact the target through the nozzle, and the I-Scan pressure sensor transmits the signal to the I-Scan signal receiver. After the jet impact, information processing is performed to obtain scientifically accurate jet impact pressure fluctuations. The operating frequency of the jet stabilizer is adjusted according to the pressure fluctuation results to meet the pressure fluctuation requirements. A cylindrical sleeve 24 is installed inside the jet vessel to fix the sample. The center of the sleeve is positioned directly opposite the nozzle to ensure that the impact position remains unchanged when the jet impacts the sample target. The reaction and breakage of the sample occur within the jet vessel, ensuring a continuous and stable jet flow.

[0037] In practical use, the required fluid pressure is calculated and determined. The operator checks the airtightness of the pipeline and interfaces, and after confirming that everything is correct, opens the pipeline valves and closes the jet system valves. The target operating pressure and temperature of the pressure gauge and thermometer are set. The sample is placed in the sleeve of the jet reactor, and the sample-target distance is adjusted according to the test requirements. The jet reactor bolts are tightened to ensure a seal. The impact force characteristic testing device is connected, and the target distance is adjusted and sealed according to the test requirements. The carbon dioxide cylinder valve is opened, allowing carbon dioxide to flow into the cold bath. Once the temperature in the cold bath reaches the set temperature, the liquid carbon dioxide is stored in the storage tank. The plunger-type booster pump is turned on to increase the pressure of the liquid carbon dioxide to the required pressure. The high-pressure carbon dioxide flows into the hot bath, where it is heated to the set temperature. The heated high-pressure carbon dioxide reaches a supercritical state and flows into the jet pressure regulator, where it is stored. After the high-pressure supercritical carbon dioxide injection is completed, the pressure stabilization system is activated, and the nitrogen replenishment pipeline is opened to fill the nitrogen storage tank with nitrogen. Simultaneously, the gas booster pump is turned on to allow nitrogen to enter the nitrogen storage chamber. Once the target pressure set on the nitrogen storage chamber pressure gauge is reached, the high-pressure nitrogen injection automatically stops. When the tank pressure falls below the target value, an automatic alarm sounds, and the operator replenishes nitrogen promptly through the nitrogen replenishment pipeline to prevent the tank from collapsing. When the storage chamber pressure is lower than the target value, nitrogen is replenished through the gas booster pump; when the storage chamber pressure is higher than the target value, excess nitrogen in the storage chamber is automatically discharged through the gas booster pump to prevent overpressure. After the pressure stabilization system is set up, the operator turns on the jet pressure regulator switch to start the jet system. At this time, the electric spark generator automatically turns on to heat the nitrogen, causing it to expand and increase in pressure. During the fluid discharge process, the two pistons move to the right to maintain pressure balance. The high-pressure supercritical carbon dioxide fluid reaches the impact force characteristic test vessel through the pipeline to impact the target body for jet impact pressure distribution and fluctuation testing. The jet passes through an I-Scan pressure sensor, which transmits the signal to an I-Scan signal receiver for information processing, thus obtaining scientifically accurate data on the jet impact pressure distribution and fluctuations. Based on the analysis results, the jet pressure regulator can operate normally when the jet impact pressure fluctuations meet the requirements; when the jet impact pressure fluctuations do not meet the requirements, the jet pressure regulator can operate normally after the electric spark generator adjusts its frequency. High-pressure supercritical carbon dioxide fluid reaches the jet reactor through pipelines, impacting the sample and causing reactions, breakage, and other related operations. After the jet is completed, the jet reactor is opened, the reacted sample is removed, and the relevant high-pressure supercritical carbon dioxide jet operation is completed. A new sample is placed in the sleeve of the jet reactor, the target distance is adjusted as required, and the jet reactor is closed, tightening the bolts on the jet reactor for sealing. The booster pump is turned on to start the next operation of the high-pressure supercritical carbon dioxide jet system. Based on the actual work needs, the actual coal body jet cutting pressure is calculated from the test analysis data. After removing the jet reactor, the nozzle is placed in advance at the jet position for jet cutting.

[0038] In practical applications, the calculations and basis for the results of each part are as follows:

[0039] When the plunger pump is working, the peak pressure of carbon dioxide output per unit time is P1, and the output volume during the peak period is V1; the low pressure is P2, and the output volume during the low period is V2. The output temperature is T0 for both. Therefore, the initial pressure fluctuation of the plunger pump output is P1-P2, the average output pressure is 1 / 2·(P1+P2), and the pressure fluctuation rate N is:

[0040]

[0041] In the formula:

[0042] N - Pressure volatility;

[0043] P1 - Peak pressure of carbon dioxide;

[0044] P2 - Low pressure of carbon dioxide;

[0045] T0 - Carbon dioxide output temperature;

[0046] According to the REFPROP property parameter lookup software provided by the National Institute of Standards and Technology (NIST), the critical pressure of carbon dioxide is 7.3773 MPa, the critical temperature is 304.1282 K, and the critical density is 467.6 kg / m³. 3 Substituting the relevant carbon dioxide parameters into the standard form of the PR equation:

[0047]

[0048] achievable

[0049] PV 3 +(26.667-8.314T)V 2 -(2133.39P+443.42Ta)V+18963.6P

[0050] +5912.326T-26.667a=0

[0051]

[0052]

[0053] a(T)=a(T c )α(T r ,ω)

[0054]

[0055] K=0.37464+1.54226ω-0.26992ω 2

[0056] In the formula:

[0057] P - Critical pressure, 7.3773 MPa;

[0058] R - gas constant, 8.314 J / (mol·K);

[0059] T - Critical temperature, 304.128 K;

[0060] V - molar volume, L / mol;

[0061] α-Temperature function;

[0062] K - Characteristic constant of carbon dioxide;

[0063] ω-CO2 eccentricity factor, 0.225.

[0064]

[0065] M - molar mass, 44 g / mol;

[0066] ρ - density, kg / m³ 3

[0067] The total output mass per unit time can be obtained from the density ρ1 during the peak period and the density ρ2 during the low period of the plunger pump.

[0068] m total =ρ1V1+ρ2V2

[0069] Given the initial volume V2 of the right cavity, the volume V3 after the piston moves, the piston position distance x, and the piston cross-sectional area S, the output density ρ3 can be calculated using the following formula:

[0070]

[0071] If the process from the plunger pump outlet to the pressure stabilizing chamber is considered as an adiabatic expansion process, then the enthalpy h0 at the plunger pump outlet is equal to that of the pressure stabilizing chamber, and the enthalpy h0(P, T0) is calculated using P = 1 / 2·(P1+P2), which can be obtained using physical property parameter lookup software.

[0072] The output pressure P3(h0, ρ3) of the pressure stabilizing chamber can be obtained using physical property parameter lookup software based on the pressure stabilizing chamber density ρ3 and enthalpy h0.

[0073] The theoretical calculations of P3 are used to initially assess the output pressure of the pressure stabilizing chamber under actual operating conditions. The actual output pressure needs to be further calibrated using the I-Scan device.

Claims

1. A supercritical carbon dioxide high-pressure jet pressure stabilizing device, characterized by: The system includes a carbon dioxide storage cylinder, a cold bath connected to the outlet of the carbon dioxide storage cylinder, a cold bath outlet connected to a liquid carbon dioxide storage tank, a storage tank outlet connected to a booster pump inlet, a booster pump outlet connected to a hot bath, and a hot bath outlet connected to a jet pressure regulator. One end of the jet pressure regulator has a nitrogen inlet pipeline, and the other end has a high-pressure supercritical carbon dioxide outlet pipeline. The high-pressure supercritical carbon dioxide outlet pipeline is connected to the jet system, which also includes an impact force characteristic testing component. The jet pressure regulator includes a horizontally placed T-shaped sealed container. It consists of two concentric cylindrical tanks, with the inner diameter of the left tank being larger than that of the right tank. Each tank contains a vertical sealing piston connected by a spring. The left tank is a nitrogen storage chamber connected to the nitrogen inlet pipeline, while the right tank is a high-pressure supercritical carbon dioxide storage chamber connected to the high-pressure supercritical carbon dioxide inlet. The left end of the left tank has a limit switch and an electric spark generator. The limit switch is located inside the left tank, and the electric spark generator is embedded in the wall of the left tank. The leftmost inner wall of the right tank has a sealing piston blocking switch.

2. The high-pressure jet flow pressure stabilizing device based on supercritical carbon dioxide according to claim 1, characterized by: Both the cold bath and the hot bath are equipped with a loop pipe for carbon dioxide circulation. Outside the loop pipe is a temperature-regulating medium jacket cavity. The jacket cavity of the cold bath contains coolant, which is supplied by an air-cooled compressor. The temperature-regulating medium of the hot bath is high-temperature silicone oil.

3. The high-pressure jet flow pressure stabilizing device based on supercritical carbon dioxide according to claim 2, characterized by: The nitrogen inlet pipeline is supplied with nitrogen from a nitrogen storage tank, which is connected to the nitrogen inlet pipeline via a gas booster pump. The nitrogen storage tank is equipped with a cooling component, a nitrogen replenishment pipeline, and an automatic alarm. The cooling component cools the recovered high-temperature nitrogen through a coolant.

4. The supercritical carbon dioxide high-pressure jet voltage stabilizing device as described in claim 3, characterized in that: The nitrogen storage chamber, high-pressure supercritical carbon dioxide storage chamber, cold bath box, hot bath box, and nitrogen storage tank are all equipped with thermometers and pressure gauges.

5. The supercritical carbon dioxide high-pressure jet voltage stabilizing device as described in claim 4, characterized in that: The impact force characteristic testing assembly includes an impact force characteristic testing vessel and a jet vessel.

6. The supercritical carbon dioxide high-pressure jet voltage stabilizing device as described in claim 5, characterized in that: The impact force characteristic test vessel includes a nozzle located at the center of the top of the impact force test vessel and an I-Scan pressure sensor located at the nozzle outlet. The I-Scan pressure sensor is connected to an I-Scan signal receiver and an information processing unit via an electrical signal. A cylindrical sleeve is provided inside the jet vessel to fix the sample, and the center of the sleeve is positioned directly opposite the nozzle.

7. The jetting method of the apparatus according to any one of claims 1-6, characterized in that, Includes the following steps: (1) Calculate and determine the required fluid pressure. The operator checks the airtightness of the pipeline and interface. After confirming that there are no errors, open the pipeline valve, close the jet system valve, and set the target operating pressure and temperature of the pressure gauge and thermometer. (2) After connecting the impact force characteristic test vessel, adjust the target distance according to the test requirements and seal it; (3) Place the sample into the sleeve in the jet reactor, adjust the sample-target distance according to the test requirements, and tighten the bolts of the jet reactor to seal it. (4) Open the valve of the carbon dioxide cylinder to allow carbon dioxide to flow into the cold bath box. After the temperature inside the cold bath box reaches the set temperature, store the liquid carbon dioxide in the storage tank. (5) Turn on the plunger booster pump and use the booster pump to increase the pressure of liquid carbon dioxide to the required pressure. The high-pressure carbon dioxide flows into the hot bath and is heated to the set temperature in the hot bath. The heated high-pressure carbon dioxide reaches the supercritical state and flows into the jet regulator and is stored in the jet regulator. (6) After the high-pressure supercritical carbon dioxide injection is completed, open the nitrogen replenishment pipeline to fill the nitrogen storage tank with nitrogen, and at the same time turn on the gas booster pump to let the nitrogen enter the nitrogen storage chamber. After the target pressure is reached by the nitrogen storage chamber pressure gauge, the high-pressure nitrogen injection will be automatically stopped. (7) When the pressure in the storage tank is lower than the target value, the automatic alarm will sound and the operator will replenish nitrogen in time through the nitrogen replenishment pipeline to prevent the storage tank from collapsing. (8) When the pressure in the gas storage chamber is lower than the target value, nitrogen is added by a gas booster pump. When the pressure in the gas storage chamber is higher than the target value, excess nitrogen in the gas storage chamber is automatically discharged by a gas booster pump to prevent the gas storage chamber from overpressure. (9) After the setup is completed, the operator turns on the jet regulator switch to start the jet system. At this time, the electric spark generator will turn on automatically to heat the nitrogen gas, causing the nitrogen gas to expand and the pressure to rise. During the process of fluid discharge, the two pistons move to the right to keep the pressure balanced. (10) High-pressure supercritical carbon dioxide fluid reaches the impact target of the impact force characteristic test vessel through the pipeline to conduct jet impact pressure distribution and fluctuation test. The jet passes through the I-Scan pressure sensor to transmit the signal to the I-Scan signal receiver and perform information processing. The working frequency of the electric spark generator is adjusted according to the test result feedback data. (11) High-pressure supercritical carbon dioxide fluid reaches the jet reactor through the pipeline to impact the sample and cause reaction and crushing operation; (12) Open the jet vessel, take out the sample after jetting, and complete the high-pressure supercritical carbon dioxide jetting operation; (13) Place the new sample into the sleeve of the jet vessel, adjust the target distance as required, close the jet vessel, tighten the bolts on the jet vessel to seal, and repeat steps (2)-(12) to complete the test; (14) After the test is completed, based on the analysis of the test results, the jet vessel is removed during the jet impact, and the nozzle is directly aimed at the coal seam that needs to be cut for jetting.

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