Visual Measurement Device and Method for Particulate Matter Motion and Deposition in Supercritical Carbon Dioxide

Abstract

This application relates to a visualization measurement device and method for the motion and deposition of particulate matter in supercritical carbon dioxide. The device includes a CO2 source, a test section, a particulate matter generation source, a particulate matter recovery device, and observation equipment. The test section includes a gas channel, a viewing window, and a temperature control unit. The gas channel inlet is connected to the output of a circulation pump, and a pressure regulator, a preheater, and a valve are installed on the connecting pipeline. The gas channel outlet is connected to the input of the circulation pump, and a particulate matter collection device, a cooling device, a back pressure valve, and the CO2 source are connected in series on the connected pipeline. A booster pump and a control valve are connected in parallel at the output of the CO2 source. Particulate matter generated by the particulate matter generation source is transported into the gas channel by supercritical CO2 gas through the gas channel inlet. The viewing window is located on the side wall of the gas channel. The temperature control unit is located on one side of the gas channel. This application enables a visual experimental study of the motion and deposition of particulate matter during supercritical CO2 dynamic circulation.

Description

Technical Field

[0001] This invention relates to the field of supercritical carbon dioxide flow research technology, and in particular to a visualization measurement device and method for particulate matter motion and deposition in supercritical carbon dioxide. Background Technology

[0002] Currently, developing advanced nuclear reactors is a crucial direction for creating a green and low-carbon energy structure. Supercritical carbon dioxide power cycles are highly efficient and compact, and hold promise for replacing traditional steam power cycles, improving boiler and reactor efficiency. However, the unique chemical properties of supercritical carbon dioxide place higher demands on the flow environment of the supercritical fluid, and the particulate matter generated during its flow in pipes has attracted widespread attention. Furthermore, supercritical carbon dioxide coolant produces impurities during operation, requiring the addition of chemical additives, which also generates particulate matter. Particulate matter deposition increases pump power consumption and reduces the heat exchange efficiency of heat exchange equipment.

[0003] Current research on particulate matter deposition focuses on dust accumulation in ventilation ducts and particulate deposition in heat exchangers and economizers, involving air and water as the fluid media. Due to the small size of the particles, current research primarily employs numerical simulations. Simulation results are compared with empirical formulas; however, experimental data is lacking, and no publicly available reports document any visualization experiments. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a visualization measurement device and method for particulate matter motion and deposition in supercritical carbon dioxide, with the aim of enabling a visual experimental study of particulate matter motion and deposition during supercritical carbon dioxide dynamic circulation.

[0005] The technical solution adopted in this invention is as follows:

[0006] This application provides a visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide, including a CO2 source, a test section, a particulate matter generation source, a particulate matter recovery device, and an observation device;

[0007] The test section includes a gas channel, a viewing window, and a temperature control unit.

[0008] The gas channel inlet is connected to the output end of the circulating pump, and a pressure regulator, a preheater and a valve are provided on the connecting pipeline. The gas channel outlet is connected to the input end of the circulating pump to form a circulation loop.

[0009] The CO2 source is connected in series in the pipeline that connects the outlet of the gas channel to the inlet of the circulating pump;

[0010] A booster pump and a control valve are connected in parallel at the output end of the CO2 source;

[0011] The particulate matter generated by the particulate matter source is transported into the gas channel by supercritical CO2 gas through the gas channel inlet;

[0012] The particulate matter recovery device is installed on the pipeline connecting the gas channel outlet and the circulation pump inlet. A cooling device is installed downstream of the particulate matter collection device on the connected pipeline, and a back pressure valve is installed downstream of the cooling device.

[0013] The viewing window is disposed on the side wall of the gas channel;

[0014] The temperature regulating unit is located on one side of the gas channel and is used to regulate the temperature of supercritical CO2 in the gas channel.

[0015] The further technical solution is as follows:

[0016] The test section is a high-temperature test section and / or a low-temperature test section;

[0017] The temperature regulation section of the high-temperature test section is a heating section used to heat the supercritical CO2 in the gas channel.

[0018] The temperature regulation section of the low-temperature test section is a cooling section used to cool the supercritical CO2 in the gas channel.

[0019] The cooling section is a cooling water channel located on one side of the gas channel, used to connect to a constant temperature water circulation system; the heating section is an electric heating element attached to one side of the gas channel.

[0020] The test sections are a high-temperature test section and a low-temperature test section. The gas channel inlets of the two test sections are connected to the output main pipe of the circulation pump through branch pipes, and the gas channel outlets of the two test sections are connected to the input main pipe of the circulation pump through branch pipes.

[0021] The gas channel inlet branch pipes of the two test sections are each connected to a particulate matter source.

[0022] A control valve is installed on the input main pipe of the circulating pump; a pressure gauge is installed on the output main pipe of the circulating pump; and control valves, thermometers, and flow meters are respectively installed on the gas channel inlet branch pipes of the two test sections.

[0023] The structure of the particulate matter generation source includes a feed pump and a particulate matter generation device, which can generate fine particulate matter with a particle size of 0.5μm-10 mm.

[0024] The fine particulate matter has fluorescent properties.

[0025] The observation equipment includes a PIV device, a PDA device, and an ultrasonic detector.

[0026] This application also provides a measurement method for the aforementioned visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide, comprising:

[0027] Open the output control valve of the CO2 source and pressurize the pipeline until the pressure reaches 5 MPa;

[0028] Close the output control valve of the CO2 source, turn on the booster pump, and pressurize the pipeline to a pressure of 8 MPa - 12 MPa. Then turn off the booster pump and turn on the circulation pump to circulate the CO2 in the circulation loop.

[0029] CO2 is heated to a set temperature of 25-100℃ by a preheater to make it reach a supercritical state. Then, the flow rate of the gas entering the test section is controlled by a valve. The supercritical CO2 is heated or cooled in the gas channel. After the supercritical CO2 flow reaches a stable state, the particulate matter generation source is turned on, so that the particulate matter is pneumatically transported from the gas channel inlet to the gas channel by the supercritical CO2.

[0030] Images of particulate matter motion and deposition were acquired using observation equipment, and data analysis and calculations were performed to obtain the motion and deposition patterns of supercritical CO2 particles under cooling or heating conditions.

[0031] After passing through the test section, the supercritical CO2 gathers in the cooling device and is cooled to room temperature. Then, it returns to the input of the circulation pump through the back pressure valve to start a new cycle.

[0032] The measurement method further includes:

[0033] Use a particulate matter collection device to collect undeposited particulate matter, preventing it from entering the cooling device and circulation pump.

[0034] The beneficial effects of this invention are as follows:

[0035] This invention effectively solves the problem of the difficulty in observing the fluid motion of supercritical CO2, and is of great significance for improving the operating efficiency and safety of supercritical CO2 reactors and supercritical carbon dioxide thermal equipment. This invention provides an observation environment for the supercritical CO2 generation environment, the particulate matter generation environment, the circulation environment of particulate matter in the supercritical CO2 pneumatic transport, and the motion and deposition patterns of airflow and particulate matter. Using observation equipment through a viewing window, the flow patterns of supercritical CO2 within the gas channel and the motion and deposition of particulate matter in the airflow can be visualized. Compared with simulation and theoretical research, the observation results are more intuitive and can provide a reliable basis for simulation and theoretical research.

[0036] This invention can measure the motion and deposition of particles under heating and cooling conditions as needed. It has the advantages of being intuitive, accurate, and fast.

[0037] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the device according to an embodiment of the present invention.

[0039] Figure 2 This is a schematic diagram of the high-temperature test section of the device in an embodiment of the present invention.

[0040] Figure 3 This is a schematic diagram of the low-temperature testing section of the device in an embodiment of the present invention.

[0041] In the diagram: 1. CO2 storage tank; 2. Booster pump; 3. Circulation pump; 4. Pressure regulator; 5. Preheater; 6. Pressure gauge; 7. Thermometer; 8. Flow meter; 9. Feed pump; 10. Particulate matter generating device; 11. Constant temperature water tank; 12. Low temperature test section; 13. High temperature test section; 14. Particulate matter collection device; 15. Cooling device; 16. Gas passage; 17. Viewing window; 18. Screw; 19. Electric heating element; 20. Cooling water passage; 21. Output main pipe; 22. Input main pipe; 23. Observation equipment. Detailed Implementation

[0042] The specific embodiments of the present invention are described below with reference to the accompanying drawings.

[0043] This application provides a visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide, including a CO2 source, a test section, a particulate matter generation source, a particulate matter recovery device, and an observation device;

[0044] The test section includes a gas channel, a viewing window, and a temperature control unit.

[0045] The gas channel inlet is connected to the output end of the circulating pump, and a pressure regulator, a preheater and a valve are provided on the connecting pipeline. The gas channel outlet is connected to the input end of the circulating pump to form a circulation loop.

[0046] The CO2 source is connected in series in the pipeline that connects the outlet of the gas channel to the inlet of the circulating pump;

[0047] A booster pump and a control valve are connected in parallel at the output end of the CO2 source;

[0048] The particulate matter generated by the particulate matter source is transported into the gas channel by supercritical CO2 gas through the gas channel inlet;

[0049] The particulate matter recovery device is installed on the pipeline connecting the gas channel outlet and the circulation pump inlet. A cooling device is installed downstream of the particulate matter collection device on the connected pipeline, and a back pressure valve is installed downstream of the cooling device.

[0050] The viewing window is disposed on the side wall of the gas channel;

[0051] The temperature regulating unit is located on one side of the gas channel and is used to regulate the temperature of supercritical CO2 in the gas channel.

[0052] This application provides a method for visually measuring the motion and deposition of particulate matter in supercritical carbon dioxide, including:

[0053] Open the output control valve of the CO2 source and pressurize the pipeline until the pressure reaches about 5 MPa.

[0054] Close the output control valve of the CO2 source, turn on the booster pump, and pressurize the pipeline to a pressure of 8 MPa - 12 MPa. Then turn off the booster pump and turn on the circulation pump to circulate the CO2 in the circulation loop.

[0055] CO2 is heated to a set temperature by a preheater to make it reach a supercritical state. Then, the flow rate of the gas entering the test section is controlled by a valve. The supercritical CO2 is heated or cooled in the gas channel. After the supercritical CO2 flow reaches a stable state, the particulate matter generation source is turned on, so that the particulate matter is pneumatically transported from the gas channel inlet to the gas channel by the supercritical CO2.

[0056] Images of particulate matter motion and deposition were acquired using observation equipment, and data analysis and calculations were performed to obtain the motion and deposition patterns of supercritical CO2 particles under cooling or heating conditions.

[0057] After passing through the test section, the supercritical CO2 gathers in the cooling device and is cooled to room temperature. Then, it returns to the input of the circulation pump through the back pressure valve to start a new cycle.

[0058] This application provides a supercritical CO2 circulation environment, a particulate matter generation environment, and an observation environment. Using observation equipment with a viewing window, the flow patterns of supercritical CO2 within the gas channel and the movement and deposition of particulate matter in the gas flow can be visualized. Compared to simulations and theoretical studies, the observation results are more intuitive and can provide a reliable basis for simulation and theoretical research.

[0059] The following specific embodiments further illustrate the visualization and measurement device for particulate matter motion and deposition in supercritical carbon dioxide of this application. See also Figure 1 The visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide in this embodiment includes a CO2 storage tank 1, a test section, a particulate matter generation source, a particulate matter recovery device 14, and an observation device 23.

[0060] The test section includes a gas channel, a viewing window, and a temperature control unit.

[0061] The test section specifically includes a high-temperature test section 13 and a low-temperature test section 12. The temperature regulation section of the high-temperature test section 13 is a heating section used to heat the supercritical CO2 in the gas channel; the temperature regulation section of the low-temperature test section 12 is a cooling section used to cool the supercritical CO2 in the gas channel.

[0062] See Figure 2 The heating element is an electric heating element 19 attached to one side of the gas channel 16.

[0063] Specifically, the two mounting parts are connected by screws 18 and form a cavity inside. The viewing window 17 is installed on one side of the cavity by fasteners, forming the gas channel 16 of the high-temperature test section 13. Supercritical CO2 flows in the gas channel 16, and the supercritical CO2 in the gas channel 16 is heated by an electric heating element 19 at the bottom, so as to realize the visualization measurement of the movement and deposition of supercritical CO2 particles under heating conditions.

[0064] See Figure 3 The cooling section is a cooling water channel 20 located on one side of the gas channel 16, which is used to connect to the constant temperature water circulation system.

[0065] Specifically, the two mounting parts are connected by screws 18, forming a cooling water channel 20 inside and a cavity outside. The viewing window 17 is mounted on one side of the cavity by fasteners, forming a gas channel 16 for the low-temperature test section 12.

[0066] Specifically, such as Figure 1 As shown, the constant temperature water circulation system includes a constant temperature water tank 11, whose inlet and outlet are connected to a cooling water channel 20 to form a circulation. Supercritical CO2 flows in the gas channel 16, and the cooling water output from the constant temperature water tank 11 flows in the cooling water channel 20 to cool the supercritical CO2 in the gas channel 16, thereby enabling visual measurement of the particle motion and deposition of supercritical CO2 under cooling conditions.

[0067] Specifically, the cooling water can be circulated in the opposite direction to the gas flow.

[0068] Specifically, the viewing window 17 can be disassembled and replaced. The gas channel 16 also has different cross-sectional shapes, such as circular, square, and narrow rectangular.

[0069] like Figure 1As shown, the gas channel inlets of high temperature test section 13 and low temperature test section 12 are respectively connected to the output main pipe 21 of circulation pump 3 through branch pipes, and the gas channel outlets of high temperature test section 13 and low temperature test section 12 are respectively connected to the input main pipe 22 of circulation pump through branch pipes 3, forming a circulation loop;

[0070] CO2 storage tank 1 is connected in series with input main pipe 22, and booster pump 2 and control valve F1 are connected in parallel at the output end of CO2 storage tank 1.

[0071] The particulate matter recovery device 14 is installed on the input main pipe 22. A cooling device 15 is installed on the input main pipe 22 downstream of the particulate matter collection device 14. A back pressure valve F5 is installed downstream of the cooling device 15. A control valve F4 is installed downstream of the back pressure valve F5 and before the inlet of the circulating pump 3. A pressure regulator 4, a preheater 5 and a pressure gauge 6 are installed on the output main pipe 21. Valves F2 and F3, as well as a thermometer 7 and a flow meter 8 are installed on the gas channel inlet branch pipes of the two test sections, respectively.

[0072] Specifically, the gas channel inlet branch pipes of the high-temperature test section 13 and the low-temperature test section 12 are each connected to a particulate matter generation source. The particulate matter generation source includes a feed pump 9 and a particulate matter generating device 10. The inlet of the feed pump 9 is connected to the upstream section of the branch pipe, the outlet of the feed pump 9 is connected to the particulate matter generating device 10, and the outlet of the particulate matter generating device 10 is connected to the downstream section of the branch pipe. The particulate matter generated by the particulate matter generation source is pneumatically transported into the gas channel by supercritical CO2 gas at the gas channel inlet.

[0073] Specifically, the particulate matter generating device 10 can generate particulate matter of different sizes, producing fine particulate matter with a particle size of 0.5μm-10 mm, and outputting a stable flow of particles under constant power. The generated particles are then transported to the gas channel by the feed pump 9.

[0074] Fine particulate matter can also be set to particulate matter with fluorescent properties, which facilitates subsequent visualization observation.

[0075] Specifically, the observation equipment 23 includes, but is not limited to, PIV (Particle Image Velocimetry) equipment, PDA (Phase Doppler Anemometer) equipment, and ultrasonic detectors.

[0076] Specifically, in this embodiment, only one test section can be set up. By changing the test section, the motion and deposition of particulate matter under heating or cooling conditions of supercritical carbon dioxide can be measured.

[0077] The measurement method using the visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide according to this embodiment includes:

[0078] Open the control valve F1 of CO2 storage tank 1 and pressurize the pipeline until the pressure reaches about 5 MPa;

[0079] Close the control valve F1 of CO2 storage tank 1, turn on booster pump 2, and pressurize the pipeline to a pressure of 8 MPa - 12 MPa. Then turn off booster pump 2 and turn on circulation pump 3 to force CO2 to circulate in the circulation loop.

[0080] CO2 is heated to a set temperature of 25-100℃ by preheater 5, so that CO2 reaches a supercritical state. Then, the flow rate of the gas entering the two test sections is controlled by valves F2 and F3. The supercritical CO2 is heated or cooled in the gas channel. After the supercritical CO2 flow reaches a stable state, the feed pump 9 and the particle generation device 10 are turned on, so that the particles are pneumatically transported into the gas channel by supercritical CO2 from the gas channel inlet.

[0081] High-speed cameras are used to capture images of particulate matter motion and deposition. Data analysis and calculations are performed to obtain the motion and deposition patterns of supercritical CO2 under cooling and heating conditions. After passing through the test section, the supercritical CO2 is collected in the cooling device 15 and cooled to room temperature. Then, it returns to the input end of the circulation pump 3 through the back pressure valve F5 for a new round of circulation.

[0082] Specifically, particulate matter collection device 14 is used to collect undeposited particulate matter, preventing it from entering the cooling device 15 and the circulating pump 3 and affecting equipment performance. The particulate matter collection device can be a demister or similar equipment.

[0083] Specifically, the preheater 5 has a temperature feedback system that can set the outlet temperature to ensure that the outlet temperature of the preheater 5 remains constant.

[0084] Specifically, the pressure of supercritical CO2 can be adjusted by booster pump 2 to achieve measurement of supercritical CO2 pressure over a wide range.

[0085] In summary, the device described in this application can both observe and study the fluid motion of supercritical CO2 during heating and cooling, analyze the flow state, and measure and study the deposition motion of particulate matter in the fluid under heated and cooled conditions, thereby obtaining its deposition patterns. The proposed device effectively solves the problem of the difficulty in observing the fluid motion of supercritical CO2, and is of great significance for improving the operating efficiency and safety of supercritical CO2 reactors and supercritical carbon dioxide thermal equipment.

[0086] It will be understood by those skilled in the art that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide, characterized in that, This includes a CO2 source, a test section, a particulate matter generation source, a particulate matter recovery device, and monitoring equipment; The test section includes a gas channel, a viewing window, and a temperature control unit. The gas channel inlet is connected to the output end of the circulating pump, and a pressure regulator, a preheater and a valve are provided on the connecting pipeline. The gas channel outlet is connected to the input end of the circulating pump to form a circulation loop. The CO2 source is connected in series in the pipeline that connects the outlet of the gas channel to the inlet of the circulating pump; A booster pump and a control valve are connected in parallel at the output end of the CO2 source; The particulate matter generated by the particulate matter source is transported into the gas channel by supercritical CO2 gas through the gas channel inlet; The particulate matter recovery device is installed on the pipeline connecting the gas channel outlet and the circulation pump inlet. A cooling device is installed downstream of the particulate matter collection device on the connected pipeline, and a back pressure valve is installed downstream of the cooling device. The viewing window is disposed on the side wall of the gas channel; The temperature regulating unit is located on one side of the gas channel and is used to regulate the temperature of supercritical CO2 in the gas channel.

2. The visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide according to claim 1, characterized in that, The test section is a high-temperature test section and / or a low-temperature test section; The temperature regulation section of the high-temperature test section is a heating section used to heat the supercritical CO2 in the gas channel. The temperature regulation section of the low-temperature test section is a cooling section used to cool the supercritical CO2 in the gas channel.

3. The visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide according to claim 2, characterized in that, The cooling section is a cooling water channel located on one side of the gas channel, used to connect to a constant temperature water circulation system; the heating section is an electric heating element attached to one side of the gas channel.

4. The visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide according to claim 2, characterized in that, The test sections are a high-temperature test section and a low-temperature test section. The gas channel inlets of the two test sections are connected to the output main pipe of the circulation pump through branch pipes, and the gas channel outlets of the two test sections are connected to the input main pipe of the circulation pump through branch pipes.

5. The visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide according to claim 4, characterized in that, The gas channel inlet branch pipes of the two test sections are each connected to a particulate matter source.

6. The visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide according to claim 4, characterized in that, A control valve is installed on the input main pipe of the circulating pump; a pressure gauge is installed on the output main pipe of the circulating pump; and control valves, thermometers, and flow meters are respectively installed on the gas channel inlet branch pipes of the two test sections.

7. The visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide according to claim 1, characterized in that, The structure of the particulate matter generation source includes a feed pump and a particulate matter generation device, which can generate fine particulate matter with a particle size of 0.5μm-10 mm. The fine particulate matter has fluorescent properties.

8. The visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide according to claim 1, characterized in that, The observation equipment includes a PIV device, a PDA device, and an ultrasonic detector.

9. A measurement method for a visualization measurement device for particulate matter motion and deposition in supercritical carbon dioxide as described in claim 1, characterized in that, include: Open the output control valve of the CO2 source and pressurize the pipeline until the pressure reaches 5 MPa; Close the output control valve of the CO2 source, turn on the booster pump, and pressurize the pipeline to a pressure of 8 MPa - 12 MPa. Then turn off the booster pump and turn on the circulation pump to circulate the CO2 in the circulation loop. CO2 is heated to a set temperature of 25-100℃ by a preheater to make it reach a supercritical state. Then, the flow rate of the gas entering the test section is controlled by a valve. The supercritical CO2 is heated or cooled in the gas channel. After the supercritical CO2 flow reaches a stable state, the particulate matter generation source is turned on, so that the particulate matter is pneumatically transported from the gas channel inlet to the gas channel by the supercritical CO2. Images of particulate matter motion and deposition were acquired using observation equipment, and data analysis and calculations were performed to obtain the motion and deposition patterns of supercritical CO2 particles under cooling or heating conditions. After passing through the test section, the supercritical CO2 gathers in the cooling device and is cooled to room temperature. Then, it returns to the input of the circulation pump through the back pressure valve to start a new cycle.

10. The measurement method according to claim 9, characterized in that, Also includes: Use a particulate matter collection device to collect undeposited particulate matter, preventing it from entering the cooling device and circulation pump.

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