System for measuring surface tension of liquid alkali metal

Abstract

The embodiment of the invention relates to the field of liquid surface tension testing, in particular to a system for measuring the surface tension of liquid alkali metal, which comprises an alkali metal container, a heating device, a gas injection piece and a pressure difference measuring piece. The alkali metal container is used for containing liquid alkali metal; the heating device is used for providing heat for the alkali metal container, so that liquid alkali metal in the alkali metal container is at a preset temperature; the gas injection part is used for injecting gas into the liquid alkali metal so as to form bubbles in the liquid alkali metal, and the bubbles can be broken; the pressure difference measuring piece is used for measuring the pressure difference before and after bubble breakage so as to determine the surface tension of the liquid alkali metal according to the pressure difference. According to the system provided by the embodiment of the invention, the bubbles capable of being broken are formed in the liquid alkali metal through the gas injection part, and the pressure difference before and after the bubbles are broken is measured through the pressure difference measurement part, so that the surface tension of the liquid alkali metal is measured, and the accuracy of a measurement result of the surface tension of the liquid alkali metal is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of testing liquid surface tension, and in particular to a system for measuring the surface tension of liquid alkali metal. Background Art

[0002] The statements herein merely provide background information related to the present application and do not necessarily constitute prior art.

[0003] As a good heat transfer medium, liquid alkali metal can be widely used in chemical, metallurgical, energy, pharmaceutical and nuclear industries. The surface tension of liquid alkali metal is an important characteristic of liquid alkali metal, which is related to the quality of liquid alkali metal. In order to improve the quality of liquid alkali metal, it is necessary to measure the surface tension of liquid alkali metal.

[0004] At present, the commonly used methods for measuring surface tension are mostly suitable for measuring the surface tension of ordinary liquids (such as water and aqueous solutions, organic solvents, etc.). However, due to the great difference in the properties of ordinary liquids and liquid alkali metals, when the surface tension of liquid alkali metals is measured using the method for measuring the surface tension of ordinary liquids, there is a problem that the measurement results of the surface tension of liquid alkali metals are not accurate enough or even the surface tension of liquid alkali metals cannot be measured. Summary of the invention

[0005] A brief overview of the present application is provided below in order to provide a basic understanding of certain aspects of the present application. It should be understood that this overview is not an exhaustive overview of the present application. It is not intended to identify the key or important parts of the present application, nor is it intended to limit the scope of the present application. Its purpose is merely to present certain concepts in a simplified form as a prelude to a more detailed description discussed later.

[0006] In the related art, the hanging ring method is often used to measure the surface tension of the liquid. When the hanging ring method is used to measure the surface tension of the liquid, the suspended metal ring needs to be immersed in the liquid to be measured. After it is completely immersed, the metal ring is pulled upward out of the liquid surface of the liquid to be measured. In this process, the metal ring will be subjected to a downward force, which includes the gravity of the metal ring and the surface tension provided by the liquid to be measured; by measuring the downward force applied to the metal ring, the surface tension provided by the liquid to be measured can be determined. However, since liquid alkali metals cannot be wetted with commonly used hanging ring materials, it is not suitable to use the hanging ring method to measure the surface tension of liquid alkali metals. Therefore, it is necessary to provide a system that can measure the surface tension of liquid alkali metals.

[0007] In order to solve the above problems, an embodiment of the present application provides a system for measuring the surface tension of liquid alkali metal, which includes an alkali metal container, a heating device, a gas injection component, and a pressure difference measuring component. The alkali metal container is used to contain liquid alkali metal; the heating device is used to provide heat to the alkali metal container so that the liquid alkali metal in the alkali metal container is at a preset temperature; the gas injection component is used to inject gas into the liquid alkali metal to form bubbles in the liquid alkali metal and enable the bubbles to burst; the pressure difference measuring component is used to measure the pressure difference before and after the bubble bursts, so as to determine the surface tension of the liquid alkali metal according to the pressure difference before and after the bubble bursts.

[0008] The system for measuring the surface tension of liquid alkali metal provided in the embodiments of the present application injects gas into the liquid alkali metal through a gas injection piece to allow bubbles to burst, and measures the pressure difference before and after the bubble burst through a pressure difference measuring piece, thereby achieving measurement of the surface tension of the liquid alkali metal, which is beneficial to improving the accuracy of the measurement results of the surface tension of the liquid alkali metal. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Other objects and advantages of the present application will become apparent from the following description of the embodiments of the present application with reference to the accompanying drawings, and will help to provide a comprehensive understanding of the present application.

[0010] Figure 1 Schematic diagram of the structure of a system for measuring the surface tension of liquid alkali metal provided in an embodiment of the present application.

[0011] Figure 2 It is a cross-sectional view of the composition of the system for measuring the surface tension of liquid alkali metal provided by an embodiment of the present application after omitting the gas injection lifting device and the glove box.

[0012] Figure 3 It is a schematic structural diagram of a gas injection lifting device of a system for measuring the surface tension of liquid alkali metal provided in an embodiment of the present application.

[0013] Description of reference numerals:

[0014] 100. Measurement system;

[0015] 10. Alkali metal container; 105. Temperature measuring element; 106. Accommodation box; 107. Fastener; 11. Sealing element; 111. Cover element; 112. Connecting element; 12. Sealing fitting element; 121. Bellows; 122. Connecting fitting element; 123. Bottom wall connecting element; 124. Sealing ring;

[0016] 20. Heating device; 21. Inner shell; 22. Shell connector; 221. Connecting cylinder; 222. Connecting flange; 23. Radial cooling element; 231. Cooling chamber; 24. Outer shell; 241. Top cover; 25. Cooling assembly; 251. First cooling element; 2511. First cooling chamber; 252. Second cooling element; 2521. Second cooling chamber; 26. Insulation layer; 261. Top insulation layer; 262. Bottom insulation layer; 263. Side insulation layer; 264. External insulation layer; 201. Heating chamber; 203. Inlet and outlet passage;

[0017] 30. Gas injection parts;

[0018] 40. Differential pressure measuring device;

[0019] 50. Gas supply parts;

[0020] 60. Gas injection lifting device; 62. Reinforcing member; 63. Support plate; 64. Moving member; 65. Moving matching member; 66. Driving member; 67. Vibration reducing member;

[0021] 70. Connecting pipe fittings;

[0022] 80, baffle; 81, main body; 82, edge; 83, through hole;

[0023] 90. Glove box; 91. Bottom wall; 92. Opening.

[0024] It should be noted that the drawings are not necessarily drawn to scale, but are merely shown in a schematic manner that does not affect the reader's understanding. DETAILED DESCRIPTION

[0025] Exemplary embodiments of the present application will be described below in conjunction with the accompanying drawings. For the sake of clarity and conciseness, not all features of the actual implementation are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the process of developing any such actual implementation in order to achieve the developer's specific goals, such as meeting those constraints related to the system and business, and these constraints may vary from implementation to implementation. In addition, it should be understood that although the development work may be very complex and time-consuming, it is only a routine task for those skilled in the art who benefit from the content of this application.

[0026] It is also necessary to explain here that, in order to avoid obscuring the present application due to unnecessary details, only the device structure and / or processing steps closely related to the scheme according to the present application are shown in the accompanying drawings, while other details that are not very relevant to the present application are omitted.

[0027] The embodiment of the present application provides a system for measuring the surface tension of liquid alkali metal (hereinafter referred to as the measurement system). Figure 1 , which may include an alkali metal container 10, a heating device 20, a gas injection member 30, and a pressure difference measuring member 40. The alkali metal container 10 is used to contain liquid alkali metal; the heating device 20 is used to provide heat to the alkali metal container 10 so that the liquid alkali metal in the alkali metal container 10 is at a preset temperature; the gas injection member 30 is used to inject gas into the liquid alkali metal to form bubbles in the liquid alkali metal and allow the bubbles to burst; the pressure difference measuring member 40 is used to measure the pressure difference before and after the bubble bursts, so that the surface tension of the liquid alkali metal can be determined according to the pressure difference before and after the bubble bursts.

[0028] The measurement system 100 provided in the embodiment of the present application injects gas into the liquid alkali metal through the gas injection component 30 to allow the bubble to burst, and measures the pressure difference before and after the bubble burst through the pressure difference measuring component 40 (that is, measuring the pressure difference immediately before the bubble burst and the pressure difference immediately after the bubble burst), thereby achieving the measurement of the surface tension of the liquid alkali metal, which is beneficial to improving the accuracy of the measurement results of the surface tension of the liquid alkali metal.

[0029] In some embodiments, the differential pressure measuring member 40 may be connected to the gas injection member 30 to measure the differential pressure before and after the bubble bursts. In some embodiments, the differential pressure measured by the differential pressure measuring member 40 may be the differential pressure between the pressure inside the gas injection member 30 and the pressure outside. The differential pressure measuring member 40 is, for example, a micro differential pressure gauge.

[0030] In some embodiments, the surface tension σ of the liquid alkali metal can be determined based on the pressure difference ΔP1 before the bubble bursts, the pressure difference ΔP2 after the bubble bursts, and the maximum inner diameter R of the bubble (ie, the inner diameter of the bubble when it is about to burst) measured by the pressure difference measuring element 40.

[0031]

[0032] △P2=P 内2 -P 外 =P 内气2 +ρgh-P 外 ;

[0033] Among them, P 内1 P is the internal pressure of the gas injection member 30 before the bubble bursts; 外 P is the external pressure of the gas injection part 30; 内气1 P is the gas pressure inside the gas injection member 30 before the bubble bursts; 内气2 is the gas pressure inside the gas injection member 30 after the bubble bursts; ρ represents the density of the liquid alkali metal, g represents the gravitational acceleration; h is the distance between the lower port of the gas injection member 30 and the liquid surface of the liquid alkali metal;

[0034] According to the above two formulas, we can get:

[0035]

[0036] Before and after the bubble bursts, the gas pressure P inside the gas injection part 30 is 内气1 and P 内气2 The following expressions are obtained:

[0037]

[0038] In the above formula, the maximum inner diameter R of the bubble is usually difficult to measure accurately. In response to this problem, the inventors of the present application found that when the gas injection part 30 is a capillary with a smaller inner diameter, the bubble formed by capillary gas injection will burst when its inner diameter is substantially equal to the inner diameter of the capillary. Therefore, in an embodiment of the present application, in order to facilitate the determination of the maximum inner diameter R of the bubble, the gas injection part 30 can be a capillary with an inner diameter less than or equal to 1 mm. At this time, the maximum inner diameter R of the bubble is the inner diameter of the capillary. In some embodiments, the gas injection part 30 can be a capillary with an inner diameter less than or equal to 0.8 mm.

[0039] Since the gas injection member 30 expands after being heated, the actual inner diameter of the gas injection member 30 is larger than the theoretical inner diameter of the gas injection member 30. In order to avoid the influence of the thermal expansion of the gas injection member 30 on the measurement of the surface tension of the liquid alkali metal, in some embodiments, the actual inner diameter of the gas injection member 30 is used to determine the maximum inner diameter R of the bubble. The actual inner diameter of the gas injection member 30 can be determined by calculation based on the theoretical inner diameter of the gas injection member 30 and the expansion characteristics of the constituent material of the gas injection member 30.

[0040] In some embodiments, the lower port of the gas injection member 30 may be located below the liquid surface of the liquid alkali metal, and bubbles may be formed at the lower port of the gas injection member 30. The gas injection rate of the gas injection member 30 may be controlled so that during the bubble formation process, a new bubble is formed only after the previous bubble ruptures, that is, there is only one bubble in the liquid alkali metal, and multiple bubbles do not exist at the same time.

[0041] In some embodiments, the amount of liquid alkali metal in the alkali metal container 10 may be two-thirds to three-quarters of the volume of the alkali metal container 10 to prevent the liquid alkali metal in the alkali metal container 10 from overflowing during bubble formation and bursting. The alkali metal container 10 is, for example, a crucible.

[0042] In some embodiments, the liquid alkali metal may be liquid sodium, liquid sodium-potassium alloy, or liquid gallium. In some embodiments, the surface tension of the liquid alkali metal is different at different temperatures, and the measurement system 100 may be used to measure the surface tension of the liquid alkali metal at different temperatures, wherein the temperature of the liquid alkali metal is in a temperature range from its melting point to a temperature close to its boiling point. For example, the measurement system 100 may be used to measure the surface tension of liquid gallium in a temperature range from room temperature to 150°C.

[0043] See also Figure 1 In some embodiments, the measurement system 100 may further include a gas provider 50 for providing a gas source to the gas injection member 30. In such an embodiment, by providing the gas provider 50 to provide gas to the gas injection member 30, it is easier to control the gas supply rate and form a single bubble in the alkali metal container 10.

[0044] In some embodiments, the gas providing member 50 can be used to provide an inert gas, such as argon, to the gas injection member 30. In some embodiments, the gas providing member 50 and the gas injection member 30 are connected by a gas supply pipeline, and a pressure regulating member and a flow regulating member are provided on the gas supply pipeline, which are respectively used to regulate the gas pressure and flow rate of the gas entering the gas injection member 30, so that the gas providing member 50 can quantitatively pass a certain flow rate of argon gas into the gas injection member 30, thereby allowing bubbles to be formed continuously (continuously here means forming a bubble-bubble bursting-forming another bubble-bubble bursting...). The pressure regulating member is, for example, a pressure regulating valve or a pressure reducing valve. In some embodiments, the flow rate of the gas of the gas injection member 30 is several milliliters per minute.

[0045] The pressure difference measuring component 40 may be disposed on the gas supply pipeline to measure the pressure difference between the inside and outside of the gas injection component 30 .

[0046] See also Figure 2 In some embodiments, the heating device 20 may form a heating chamber 201 and an inlet and outlet channel 203 communicating with the heating chamber 201. Figure 3 In some embodiments, the measurement system 100 may further include a container lifting device and a gas injection lifting device 60. The container lifting device is used to drive the alkali metal container 10 to enter the heating chamber 201 or leave the heating chamber 201 through the inlet and outlet channel 203. The gas injection lifting device 60 is used to drive the gas injection part 30 to enter the heating chamber 201 through the inlet and outlet channel 203 to enter the alkali metal container 10 or leave the heating chamber 201.

[0047] In such an embodiment, the alkali metal container 10 is driven to enter or leave the heating chamber 201 by the container lifting device, and the alkali metal container 10 can be heated by the heating device 20, and the alkali metal container 10 is also convenient for cleaning; the gas injection lifting device 60 is used to drive the gas injection component 30 to enter or leave the heating chamber 201, so that the lower port of the gas injection component 30 can enter below the liquid surface of the liquid alkali metal, so as to realize the measurement of the surface tension of the liquid alkali metal.

[0048] See also Figure 1 In some embodiments, the container lifting device and the gas injection lifting device 60 may be disposed in the glove box 90. The heating chamber 201 may be disposed below the bottom wall 91 of the glove box 90. The bottom wall 91 of the glove box 90 forms an opening 92; the inlet and outlet channel 203 is connected to the glove box 90 through the opening 92.

[0049] In some embodiments, the glove box 90 can be used to provide an inert gas environment for measuring the surface tension of liquid alkali metals. Since liquid alkali metals such as liquid sodium, liquid potassium, etc. can react with water, oxygen, carbon dioxide, etc. to generate substances such as oxides and carbonates, these substances will form a layered structure on the surface of the liquid alkali metal in the form of an amorphous multiphase solid, affecting the accuracy of the measurement results of the surface tension of the liquid alkali metal. In an embodiment of the present application, an inert gas environment is provided for measuring the surface tension of the liquid alkali metal through the glove box 90, which can avoid the reaction of the liquid alkali metal with water, oxygen, carbon dioxide, etc., and is conducive to improving the accuracy of the measurement results of the surface tension of the liquid alkali metal. In some embodiments, the glove box 90 can use an inert gas as a protective gas, such as argon.

[0050] See also Figure 3 In some embodiments, the gas injection lifting device 60 may include a support plate 63, a moving member 64, a moving matching member 65, and a driving member 66. The support plate 63 is configured to be connected to the gas injection member 30 and the moving member 64; the driving member 66 is configured to drive the moving member 64 to move vertically relative to the moving matching member 65, so as to drive the gas injection member 30 to enter or leave the heating chamber 201.

[0051] In some embodiments, the support plate 63 is formed with a through hole for the gas injection member 30 to pass through.

[0052] See also Figure 3 In some embodiments, the gas injection lifting device 60 may further include a vibration damping member 67 connected to the support plate 63, which is used to reduce the vibration amplitude of the gas injection member 30 caused by the gas injection lifting device 60 driving the gas injection member 30 to rise and fall, so as to ensure the accuracy of the measurement of the surface tension of the liquid alkali metal.

[0053] In some embodiments, the vibration damping member 67 may include a plurality of steel plates vertically overlapped and arranged. In such an embodiment, the plurality of steel plates are equivalent to forming a counterweight, so that the vibration damping member 67 can reduce the vibration amplitude of the gas injection member 30 when it is lifted or lowered.

[0054] In some embodiments, the center of gravity of the support plate 63 and the gas injection component 30 is located on multiple steel plates, that is, the vertical line of the center of gravity of the support plate 63 and the gas injection component 30 passes through multiple steel plates, which is beneficial to reduce the vibration amplitude of the gas injection component 30 when it is lifted or lowered.

[0055] See also Figure 3 In some embodiments, the gas injection lifting device 60 may further include a reinforcement member 62 for reinforcing the plurality of steel plates. In such an embodiment, since the plurality of steel plates are heavy, reinforcing them by the reinforcement member 62 is beneficial to improving the stability of the plurality of steel plates. In some embodiments, the reinforcement member 62 is, for example, a triangular steel plate, and the two right-angled sides of the triangular steel plate are respectively connected to the plurality of steel plates and the moving member 64 to reinforce the plurality of steel plates.

[0056] In some embodiments, the container lifting device may include a moving part, a moving matching part, and a driving part. The moving part is connected to the alkali metal container 10, and the driving part drives the moving part to move vertically relative to the moving matching part to drive the alkali metal container 10 to rise and fall. In some embodiments, the gas injection lifting device 60 may be disposed on the moving part of the container lifting device.

[0057] In some embodiments, the measurement system 100 may further include a containing box 106 disposed at the bottom of the glove box 90. The heating device 20 may be disposed in the containing box 106.

[0058] See also Figure 2 In some embodiments, the measuring system 100 may further include a connecting pipe 70, through which the alkali metal container 10 is connected to the container lifting device, and the connecting pipe 70 enters or leaves the heating chamber 201 through the inlet and outlet passage 203. In some embodiments, the gas injection member 30 may be located radially inside the connecting pipe 70. In such an embodiment, the alkali metal container 10 is connected to the container lifting device through the connecting pipe 70, which is conducive to improving the stability of the alkali metal container 10 in the process of being driven by the container lifting device.

[0059] In some embodiments, the measuring system 100 may further include a container connector, the alkali metal container 10 is disposed on the container connector, and the container connector is connected to the connecting pipe 70; the container lifting device can drive the connecting pipe 70 to move, and then can drive the container connector and the alkali metal container 10 to move, so that the alkali metal container 10 can enter or leave the heating chamber 201 through the inlet and outlet channel 203. In some embodiments, the container connector can be a frame structure capable of accommodating a cup-shaped container, such as a basket.

[0060] See also Figure 2 In some embodiments, the measuring system 100 may further include a multi-layer baffle 80, which is disposed at intervals on the connecting pipe 70 along the extension direction of the connecting pipe 70 to reduce the diffusion of the alkali metal vapor to the outside. In such an embodiment, by providing the multi-layer baffle 80 to reduce the diffusion of the alkali metal vapor to the outside, the leakage of the alkali metal vapor can be avoided. In some embodiments, the number of layers of the multi-layer baffle 80 may be 4 to 6, for example, 4.

[0061] See also Figure 2 In some embodiments, the baffle 80 may include a main body 81 located radially inward, and the main body 81 extends obliquely downward from the connecting pipe 70 toward the radially outward. The arrangement of the main body 81 extending obliquely downward from the connecting pipe 70 toward the radially outward is conducive to the steam entering the connecting pipe 70 and the alkali metal vapor after condensation dripping downward.

[0062] In some embodiments, the baffle 80 may further include an edge portion 82, which extends vertically downward from the radially outer end of the main body 81. In such an embodiment, the edge portion 82 extending vertically downward from the radially outer end of the main body 81 is conducive to preventing the alkali metal vapor entering the baffle 80 from flowing upward along the gap outside the baffle 80, thereby facilitating the reduction of the vapor pressure in the heating chamber 201, thereby reducing the vaporization of the alkali metal during the measurement process.

[0063] See also Figure 2 In some embodiments, the heating device 20 may include an outer shell 24, an inner shell 21, an insulation layer 26, a heating element, a cooling assembly 25, and a shell connector 22. The inner shell 21 is disposed inside the outer shell 24, and the inner shell 21 forms a heating chamber 201; the insulation layer 26 is disposed between the inner shell 21 and the outer shell 24, and is used to keep the inner shell 21 warm; the heating element is disposed in the insulation layer 26, and is used to heat the inner shell 21. The shell connector 22 is disposed outside the outer shell 24, and the shell connector 22 is connected to the inner shell 21, and the shell connector 22 forms an inlet and outlet channel 203, and the shell connector 22 is also sealed and connected to the periphery of the opening 92 of the glove box 90. By providing the shell connector 22, the inner shell 21 and the glove box 90 are connected, which is conducive to improving the sealing of the heating chamber 201.

[0064] The inventor of the present application has found that since the shell connector 22 is connected to the inner shell 21, the temperature is relatively high, which will increase the temperature of the bottom wall 91 of the glove box 90 connected to the shell connector 22, thereby adversely affecting the sealing of the glove box 90. Therefore, in some embodiments, the measurement system 100 further includes a cooling component 25 for cooling the shell connector 22. In the embodiment of the present application, the cooling component 25 is provided to cool the shell connector 22, thereby preventing the bottom wall 91 of the glove box 90 from being too high and adversely affecting the sealing of the glove box 90.

[0065] See also Figure 2 In some embodiments, the shell connector 22 may include a connecting cylinder 221 and a connecting flange 222. The connecting flange 222 is arranged at one end of the connecting cylinder 221 away from the heating chamber 201. The connecting cylinder 221 is connected to the inner shell 21, and the connecting flange 222 is sealed and connected to the periphery of the opening 92 of the glove box 90.

[0066] In some embodiments, the cooling assembly 25 may include a first cooling member 251 sleeved on the connecting cylinder 221, for cooling the connecting cylinder 221. The first cooling member 251 forms a first cooling cavity 2511, and the first cooling cavity 2511 is connected to an external cooling water system, and the connecting cylinder 221 is cooled by circulating cooling water of the cooling water system through the first cooling cavity 2511.

[0067] The inventor of the present application found that, since the inner shell 21 is connected to the top cover 241 of the outer shell 24, the heat of the inner shell 21 will be transferred to the top cover 241, and then transferred to the bottom wall 91 of the glove box 90 in the form of heat radiation. In view of this problem, in some embodiments, the cooling assembly 25 may also include a second cooling member 252, which is located below the first cooling member 251 and is sleeved on the connecting cylinder 221, and is used to cool the connecting cylinder 221 and the top cover 241 of the outer shell 24. The second cooling member 252 forms a second cooling cavity 2521, which is also connected to the external cooling water system, and the top cover 241 of the outer shell 24 and the connecting cylinder 221 are cooled by circulating the cooling water of the cooling water system through the second cooling cavity 2521.

[0068] In some embodiments, the second cooling cavity 2521 substantially covers the top cover 241 of the outer shell 24 to prevent the heat of the heating cavity 201 from being transferred to the bottom wall 91 of the glove box 90 in the form of heat radiation. In the embodiment of the present application, the first cooling member 251 and the second cooling member 252 are provided, which greatly reduces the heat transfer from the inner shell 21 to the bottom wall 91 of the glove box 90.

[0069] In some embodiments, the height of the baffle 80 located at the bottom among the plurality of baffles 80 is lower than the top cover 241, and the height of at least one baffle among the plurality of baffles 80 may be higher than the top cover 241, so as to be located radially inside the cooling assembly 25. In such an embodiment, the lower baffle 80 is conducive to heat preservation of the heating chamber 201, and the upper baffle 80 is conducive to liquefying the alkali metal vapor by using the cold provided by the cooling assembly 25. Since the main body 81 extends downwardly and obliquely from the connecting pipe 70 toward the radial outside, it is conducive to guiding the steam into the connecting pipe 70, maintaining the temperature in the connecting pipe 70, and avoiding the condensation of the alkali metal vapor on the surface of the gas injection member 30 due to the low temperature near the surface of the gas injection member 30, thereby reducing the alkali metal residue on the surface of the gas injection member 30 and avoiding affecting the accuracy of the measurement result of the surface tension of the liquid alkali metal.

[0070] See also Figure 2 In some embodiments, the thermal insulation layer 26 may include a top thermal insulation layer 261, a bottom thermal insulation layer 262, a side thermal insulation layer 263, and an external thermal insulation layer 264. The top thermal insulation layer 261 and the side thermal insulation layer 263 are arranged on the radially outer side of the inner shell 21, and the side thermal insulation layer 263 can connect the top thermal insulation layer 261 and the bottom thermal insulation layer 262; the external thermal insulation layer 264 is arranged on the radially outer side of the top thermal insulation layer 261, the bottom thermal insulation layer 262, and the side thermal insulation layer 263, and is used to connect the top thermal insulation layer 261, the bottom thermal insulation layer 262, and the side thermal insulation layer 263.

[0071] In some embodiments, the heating device 20 may further include a radial cooling member 23, which is disposed radially outside the heat-insulating layer 26 and is used to make the temperature of the heating chamber 201 uniform. In such an embodiment, by making the temperature of the heating chamber 201 uniform, it is possible to avoid condensation of alkali metal vapor on the surface of the gas injection member 30 due to the low temperature near the surface of the gas injection member 30, thereby reducing the alkali metal residue on the surface of the gas injection member 30 and avoiding affecting the accuracy of the measurement result of the surface tension of the liquid alkali metal.

[0072] The heating element is, for example, an electric heating element.

[0073] In some embodiments, the temperature difference of each part of the heating chamber 201 can be made not more than 1°C by the radial cooling member 23. In some embodiments, the radial cooling member 23 forms an annular cooling chamber 231, and a spirally extending coil is arranged in the cooling chamber 231 for cooling water to flow, and heat is exchanged between the cooling water and the heating chamber 201 to make the temperature of the heating chamber 201 uniform.

[0074] See also Figure 2In some embodiments, the measurement system 100 may further include a seal 11 and a seal fitting 12. The seal 11 is connected to the container lifting device, and the alkali metal container 10 is connected to the seal 11. The seal fitting 12 is disposed in the glove box 90. When the container lifting device drives the alkali metal container 10 to move downward to enter the heating chamber 201, the seal 11 can be sealed with the seal fitting 12 to seal the heating chamber 201, so as to reduce the diffusion of alkali metal vapor into the glove box.

[0075] In some embodiments, the sealing member 11 includes a cover member 111 and a connector 112 disposed on the periphery of the cover member 111. The sealing fitting 12 includes: a bellows 121, a connector fitting 122, and a sealing ring 124. The bellows 121 is disposed in the glove box 90 and is sealed and connected to the periphery of the opening 92. The sealing ring 124 is disposed on the connector fitting 122. The connector fitting 122 is disposed at the top of the bellows 121. When the container lifting device drives the alkali metal container 10 to move downward to enter the heating chamber 201, the connector 112 can compress the bellows 121 and seal the connector fitting 122. In such an embodiment, in the process of the container lifting device driving the alkali metal container 10 to move downward to enter the heating chamber 201, the connector 112 can first contact the connector fitting 122 and compress the bellows 121 until the alkali metal container 10 descends to the measuring position. The connection piece 112 and the connection fitting piece 122 are subjected to the force of the bellows 121 and the force applied by the container lifting device, which is more conducive to the sealing between the two. In addition, since there is a certain distance between the connection piece 112 and the connection fitting piece 122 and the bottom wall 91 of the glove box 90 (at least a distance greater than the length of the bellows 121 after compression), it is more conducive to clamping the connection piece 112 and the connection fitting piece 122 using a clamping device such as a clamp, thereby further strengthening the sealing between the two and further reducing the leakage of alkali metal.

[0076] The connector 112 and the connector fitting 122 may be quick-release flanges, such as KF flanges. During operation, the cover 111 and the bellows 121 can be separated by only touching the KF flange connection between the connector 112 and the connector fitting 122, which is easy to operate.

[0077] See also Figure 2 In some embodiments, a bottom wall connector 123 is formed at one end of the bellows 121 facing the bottom wall 91 of the glove box 90, and the bellows 121 is connected to the bottom wall 91 through the bottom wall connector 123. In some embodiments, the bellows 121 is also sealed and connected to the periphery of the opening 92 of the glove box 90 through the bottom wall connector 123. The bottom wall connector 123 may be, for example, a flange.

[0078] In some embodiments, the measuring system 100 may further include a temperature measuring element 105, which is disposed on the cover 111 and is used to measure the temperature of the liquid alkali metal in the alkali metal container 10. The heating device 20 may adjust the heating power according to the temperature measured by the temperature measuring element 105 so that the liquid alkali metal in the alkali metal container 10 is at the measuring temperature.

[0079] The temperature measuring element 105 may be, for example, a thermocouple. In some embodiments, the temperature measuring element 105 may extend from the cover 111 to near the liquid surface of the liquid alkali metal to measure the temperature of the liquid alkali metal.

[0080] In some embodiments, a through hole 83 is formed at a position corresponding to the multi-layer baffle 80 for the temperature measuring element 105 to pass through. When the temperature measuring element 105 passes through the through hole 83, it does not contact the baffle 80, so as to avoid the baffle 80 affecting the measurement result of the temperature measuring element 105 and ensure the temperature measurement accuracy of the temperature measuring element 105.

[0081] In some embodiments, the temperature measuring component 105 is set on the cover 111 through the fastener 107. When the container lifting device drives the connecting pipe 70 to move, the cover 111 moves with the connecting pipe 70, and the temperature measuring component 105 can move with the cover 111 through the fastener 107.

[0082] In some embodiments, the measurement system 100 may further include an electrical measurement system 100 for automatic control and recording of surface tension measurement. In some embodiments, the electrical measurement system 100 may include a computer, which can control the container lifting device and the gas injection lifting device 60 to achieve automatic lifting of the two; the computer can also control the heating element to achieve controllable heating and constant temperature heating of the heating element; the computer can also record the temperature of the heating element and the pressure difference measured by the pressure difference measuring element 40, and calculate the surface tension of the alkali metal.

[0083] See also Figure 1 , the process of measuring the surface tension of liquid sodium using the measurement system 100 provided in an embodiment of the present application is described below.

[0084] First, the mode of the glove box 90 is set to the circulation purification mode. When the water and oxygen content in the glove box 90 is less than or equal to 1 μL / L, the surface tension of the liquid sodium is measured.

[0085] Afterwards, the container lifting device is controlled by a computer to make the alkali metal container 10 leave the heating chamber 201 from the inlet and outlet channel 203, and the solid metallic sodium sample is loaded into the alkali metal container 10, ensuring that the liquid sodium formed after the added solid metallic sodium is melted can immerse the lower end of the capillary 30; the alkali metal container 10 containing the solid metallic sodium sample is placed on the container connector.

[0086] Afterwards, the container lifting device is controlled by a computer to allow the alkali metal container 10 to enter the heating chamber 201 , and the heating chamber 201 is sealed by the sealing member 11 ; external cooling water is allowed to enter each cooling member to cool the heating chamber 201 and the shell connector 22 .

[0087] Afterwards, the heating element is controlled by a computer to set the heating rate of the heating chamber 201 to 2-5°C / min, and the constant temperature heating time to 120min. After the constant temperature heating is completed, the capillary 30 is driven downward by the gas injection lifting device 60 to gradually immerse it in liquid sodium, and argon gas at a certain flow rate is quantitatively introduced into the capillary 30, thereby generating bubbles at the bottom of the capillary 30, and the pressure difference before and after the bubble burst is measured by the micro differential pressure meter 40 through the computer.

[0088] Finally, the surface tension of the liquid sodium is determined by a computer based on the pressure difference before and after the bubble burst measured by the micro differential pressure meter 40, the inner diameter of the capillary 30, and the distance between the lower port of the capillary 30 and the liquid surface of the liquid sodium.

[0089] Regarding the embodiments of the present application, it should also be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other to obtain new embodiments.

[0090] The above are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. The protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A system for measuring the surface tension of a liquid alkali metal, characterized in that: include: an alkali metal container for containing liquid alkali metal; A heating device, used to provide heat to the alkali metal container so that the liquid alkali metal in the alkali metal container is at a preset temperature; A gas injection member, used for injecting gas into the liquid alkali metal to form bubbles in the liquid alkali metal and enable the bubbles to burst; The pressure difference measuring member is used to measure the pressure difference before and after the bubble bursts, so as to determine the surface tension of the liquid alkali metal according to the pressure difference before and after the bubble bursts.

2. The system according to claim 1, characterized in that The gas injection piece is a capillary tube with an inner diameter less than or equal to 1 mm.

3. The system according to claim 1, characterized in that Also includes: The gas providing member is used for providing a gas source to the gas injection member.

4. The system according to claim 1, characterized in that The heating device forms a heating chamber and an inlet and outlet passage communicating with the heating chamber; The system further comprises: A container lifting device, used for driving the alkali metal container to enter the heating chamber or leave the heating chamber through the entry and exit passage; The gas injection lifting device is used to drive the gas injection component to enter the heating chamber through the inlet and outlet channel and thus enter the alkali metal container or leave the heating chamber.

5. The system according to claim 4, characterized in that The container lifting device and the gas injection lifting device are arranged in the glove box; the bottom wall of the glove box forms an opening; The heating chamber is arranged below the glove box, and the inlet and outlet passage is communicated with the glove box through the opening.

6. The system according to claim 5, characterized in that Also includes: A connecting pipe, through which the alkali metal container is connected to the container lifting device, and the connecting pipe enters or leaves the heating chamber through the inlet and outlet passage; The gas injection component is located radially inside the connecting pipe component.

7. The system according to claim 6, characterized in that Also includes: The multi-layer baffles are arranged on the connecting pipe at intervals along the extending direction of the connecting pipe, and are used to reduce the diffusion of alkali metal vapor to the outside.

8. The system according to claim 5, characterized in that The heating device comprises: shell; An inner shell is disposed in the outer shell, and the inner shell forms the heating chamber; A heat-insulating layer, disposed between the inner shell and the outer shell, for heat-insulating the inner shell; A heating element, disposed in the thermal insulation layer, for heating the inner shell; A shell connector, disposed outside the outer shell, connected to the inner shell, forming the inlet and outlet passage, and further sealed to the periphery of the opening of the glove box; A cooling component is arranged outside the shell and is used to cool the shell connector.

9. The system according to claim 8, characterized in that The housing connector includes a connecting cylinder and a connecting flange; the cooling assembly includes: A first cooling member, sleeved on the connecting cylinder member, for cooling the connecting cylinder member; The second cooling member is sleeved on the connecting cylinder member below the first cooling member and is used for cooling the connecting cylinder member and the top cover of the outer shell.

10. The system according to claim 5, characterized in that Also includes: a sealing member, the sealing member being connected to the container lifting device, and the alkali metal container being connected to the sealing member; A sealing fitting is arranged in the glove box. When the container lifting device drives the alkali metal container to move downward to enter the heating chamber, the sealing fitting can be sealingly matched with the sealing fitting to seal the heating chamber.

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