Device and method for measuring specific heat capacity at constant pressure of liquid

Abstract

The invention discloses a device for measuring the constant-pressure specific heat capacity of liquid. The device comprises a laser heating system, a temperature measuring system, a pneumatic suspension system, a sample operating system and a gas component regulation and control system. The laser heating system heats and melts a sample, and the temperature measuring system measures temperature data of the sample under a high-temperature condition. And the gas component regulation and control system is communicated with the pneumatic suspension system and the sample operating system. The pneumatic suspension system comprises a sealed cavity, and a suspension base, a nozzle and a storage table are arranged in the sealed cavity. The storage table can store samples, and the nozzle is installed on the suspension base and used for suspending the samples. The sample operating system includes an operating lever for operating the sample to move between the storage table and the nozzle. According to the measuring device, the spherical sample with the diameter of 2-4mm can be suspended by using the nozzle, the temperature of the sample is measured by using the infrared two-color thermometer, the measuring process is in a non-contact mode, and the reaction of measured liquid and a container material at high temperature can be avoided.

Description

Technical Field

[0001] The present invention relates to the field of high-temperature liquid physical property measurement, and in particular to a device for measuring the constant-pressure specific heat capacity of liquid under high-temperature conditions. Background Art

[0002] Specific heat capacity is a core parameter in material thermodynamics, directly related to a material's internal energy, enthalpy, entropy, and Gibbs free energy. Specific heat capacity plays a crucial role in the study of energy storage and transfer efficiency in high-temperature fluids, directly impacting the accuracy of solutions to fluid energy equations and the reliability of multi-physics coupled calculations.

[0003] Currently, the main methods for measuring the specific heat capacity of fluids include differential scanning calorimetry, adiabatic calorimetry, flow calorimetry, and pulse heating. Differential scanning calorimetry offers high measurement accuracy, but its applicable temperature is generally below 1600°C. Adiabatic calorimetry can be used to measure the specific heat capacity of fluids in the medium- to high-temperature range of 600-2000°C, but the equipment is complex and time-consuming. Flow calorimetry allows for dynamic measurement, but requires precise flow control and consideration of heat loss compensation. Pulse heating offers the advantage of rapid measurement, but requires the measured fluid to have high thermal conductivity, such as liquid metal, and requires both density and thermal conductivity as input parameters, making it difficult to apply to high-temperature oxide materials. Differential scanning calorimetry, adiabatic calorimetry, flow calorimetry, and pulse heating are all contact methods, and reactions between the measured fluid and the container material are difficult to avoid at high temperatures. Therefore, they are rarely used to measure the specific heat capacity of fluids above 2000°C.

[0004] In summary, existing specific heat capacity measuring devices have the problems of low temperature upper limit and reaction between the measured liquid and the container material at high temperature, which makes it difficult to meet the measurement requirements of the specific heat capacity of high-temperature liquids. Therefore, it is necessary to develop a specific heat capacity measuring device for high-temperature liquids.

[0005] In view of the above technical problems, the present invention is specially introduced. Summary of the Invention

[0006] The main purpose of the present invention is to provide a device for measuring the specific heat capacity of liquid at constant pressure, which can meet the measurement requirements of the specific heat capacity of high-temperature liquids and avoid the reaction between the measured liquid and the container material.

[0007] In order to achieve the above-mentioned objectives, the present invention provides a device for measuring the constant-pressure specific heat capacity of a liquid. The measuring device includes a laser heating system and a temperature measurement system. The laser heating system heats and melts the sample, and the temperature measurement system measures the temperature data of the sample under high-temperature conditions. The measuring device also includes: a pneumatic suspension system, the pneumatic suspension system includes a sealed chamber, a suspension base, a nozzle and a storage table are arranged in the sealed chamber, the storage table can store the sample, the nozzle is installed on the suspension base, and the nozzle is used to suspend the sample; a sample operating system, the sample operating system includes an operating rod, and the operating rod is used to operate the sample to move between the storage table and the nozzle; a gas component control system, and the gas component control system is connected to the pneumatic suspension system and the sample operating system.

[0008] The following is a further optimization of the above scheme by the present invention:

[0009] Furthermore, the gas component control system includes a pump, a first gas source and a second gas source. The pump is used to extract gas from the sealed chamber; the first gas source is connected to the suspension base to provide gas for the pneumatic suspension system and keep the pressure in the sealed chamber constant; the second gas source is connected to the operating rod to adjust the pressure inside the operating rod.

[0010] Furthermore, the gas component control system includes a first gas supply branch and a second gas supply branch, and the first gas source can be selectively connected to the first gas supply branch or the second gas supply branch; the first gas supply branch includes a first high-pressure gas tank and a first pressure reducing valve, and the second gas supply branch includes a second high-pressure gas tank and a second pressure reducing valve; the first high-pressure gas tank contains a first inert gas, and the second high-pressure gas tank contains a second inert gas.

[0011] Furthermore, the measuring device also includes a temperature measuring controller, which receives temperature data and fits the temperature data to obtain the constant-pressure specific heat capacity.

[0012] Furthermore, the measuring device also includes a sample monitoring system, which includes a high-speed camera and can monitor the suspension state of the sample.

[0013] Furthermore, the pump includes a dry pump and a molecular pump, and the dry pump and the molecular pump are connected to the sealed chamber to extract the impurity gas in the sealed chamber.

[0014] Furthermore, the operating rod is connected to a dry pump, which pumps the internal pressure of the operating rod so that the operating rod can absorb the sample; the operating rod is also connected to a second gas source, receiving gas from the second gas source, so that the sample can be separated from the operating rod.

[0015] Furthermore, the laser heating system includes at least two concave reflectors and at least two lasers. The lasers are arranged on the side of the suspension base, and concave reflectors are respectively arranged above and below the nozzle gas flow direction.

[0016] Furthermore, the sealed chamber is also provided with a top laser transmission window and a purge. The top laser transmission window is used to transmit the laser emitted by the laser. The purge is arranged adjacent to the top laser transmission window to prevent the sample from volatilizing and depositing on the top laser transmission window.

[0017] Furthermore, the gas component control system also includes a third gas source, which supplies gas to the purge device.

[0018] Furthermore, the gas component control system also includes a speaker, which is arranged on the air intake pipe below the suspension base. The sound waves generated by the speaker can be transmitted to the sample along the air intake pipe.

[0019] Furthermore, the temperature measurement system includes an infrared two-color thermometer, which can record the temperature data of the sample during the rapid cooling process.

[0020] According to another aspect of the present invention, a method for measuring the constant-pressure specific heat capacity of a liquid is also provided, using any of the above-mentioned measuring devices, comprising the following steps: a sample loading step S1: loading the sample onto a storage table; a vacuuming step S2: vacuuming the sealed chamber using a dry pump and a molecular pump; a filling inert gas step S3: filling the sealed chamber with a first inert gas or a second inert gas from a first gas source; a sample suspension step S4: using an operating lever to transfer the sample from the storage table to the nozzle, opening the first gas source to suspend the sample through the inert gas; a sample heating and melting step S5: using a laser to heat and melt the sample, reaching a specified temperature and waiting for the temperature to stabilize, turning off the laser, and simultaneously using an infrared two-color thermometer to record the temperature data of the sample during the rapid cooling process.

[0021] Furthermore, the measurement method also includes a gas source switching step S6. In step S6, after the sample is cooled, the sample is transferred from the nozzle back to the storage table, and the vacuum operation is repeated. Then, the branch of the first gas source is adjusted and switched to another inert gas to obtain temperature data of another set of samples during the rapid cooling process.

[0022] Furthermore, the measurement method further includes a data fitting step S7, in which the two sets of temperature data are fitted to obtain the constant-pressure specific heat capacity.

[0023] The application of the technical solution of the present invention achieves at least the following beneficial effects:

[0024] 1. Use a nozzle to suspend a spherical sample with a diameter of 2-4mm, and use an infrared two-color thermometer to measure the sample temperature. The measurement process is non-contact, which can avoid the reaction between the measured liquid and the container material at high temperature;

[0025] 2. Using a more efficient laser heating method, the sample temperature can reach over 3000°C;

[0026] 3. The pneumatic suspension method has little restriction on the material to be measured, and the measurement object is suitable for metal and non-metal materials;

[0027] 4. The sealed chamber uses dry pump and molecular pump to pump air, which can reach 1e -4 The ultimate vacuum degree of Pa level can fully expel the impurity gas in the sealed chamber, prevent the reaction between high temperature samples and impurity gases such as oxygen, and also realize the regulation of gas composition;

[0028] 5. The storage table can store six spherical samples at a time. The L-shaped operating rod and sealed bellows can flexibly transfer the samples between the storage table and the nozzle. Therefore, after one vacuum to remove impurity gases, six experiments can be carried out under the same gas composition conditions without repeated vacuuming, which improves experimental efficiency.

[0029] 6. Both the gas outlets of the exhaust port and the operating rod are connected to filters to prevent volatile materials from escaping outside the sealed chamber. In addition, the purge device blows air toward the top laser transmission window to prevent volatile materials from being deposited on the top laser transmission window, reducing the risk of ZnSe lens failure and improving the applicability of measuring volatile materials.

[0030] 7. The measuring device can be used not only to measure the constant pressure specific heat capacity of high temperature liquid, but also to measure the density, surface tension and viscosity of high temperature liquid. The device has a high degree of integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0032] Figure 1 A schematic structural diagram of a device for measuring the specific heat capacity of liquid at constant pressure under high temperature conditions provided by the present invention;

[0033] Figure 2 It is an exploded view of the main body of the device of the present invention;

[0034] Figure 3 It is a schematic cross-sectional view of the main body of the device of the present invention;

[0035] Figure 4 Schematic diagram of the gas pipeline structure of the device of the present invention;

[0036] Figure 5 This is a schematic diagram of the operating lever structure of the device of the present invention;

[0037] Figure 6 Schematic diagram of the gas source structure of the device of the present invention.

[0038] The above drawings include the following reference numerals:

[0039] 1. Nozzle; 2. Suspension base; 3. Bracket; 4. Optical platform; 5. Gas inlet; 6. Cooling water inlet; 7. Cooling water outlet; 8. Laser; 9. Concave reflector; 10. Infrared dual-color thermometer; 11. Joystick; 12. Sealed bellows; 13. High-speed camera; 14. Sealed chamber; 15. Vacuum port; 16. Purge; 17. Pressure sensor; 18. Storage platform; 19. Top laser transmission window; 20. Temperature measurement window; 21. Cooling water loop; 22. Storage platform window ; 23. Side viewing window; 24. Bottom laser transmission window; 25. First gas source; 26. Flow controller; 27. Angle valve; 28. Filter; 29. ​​Needle valve; 30. Pressure relief valve; 31. Dry pump; 32. Molecular pump; 33. Speaker; 34. Operating lever body; 35. Removable nozzle; 36. Groove; 37. First high-pressure gas tank; 38. First pressure reducing valve; 39. Three-way connector; 40. Second gas source; 41. Third gas source; 42. Second high-pressure gas tank; 43. Second pressure reducing valve. DETAILED DESCRIPTION

[0040] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0041] The present invention is described in further detail below with reference to specific embodiments. These embodiments are not to be construed as limiting the scope of protection claimed by the present invention. The term "including" when used indicates the presence of a feature, but does not exclude the presence or addition of one or more other features; the terms "lateral", "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for ease of description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be construed as limiting the present invention; in addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be construed as indicating or implying relative importance.

[0042] In the description, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, an indirect connection through an intermediate medium, or a communication between the two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more. The steps of the present invention are not limited to the order listed, and the order of the steps can be adjusted as needed.

[0043] The present invention provides a device for measuring the constant-pressure specific heat capacity of liquid under high-temperature conditions. The device adopts a non-contact method, can measure temperatures exceeding 3000°C, and is applicable to metal and non-metal materials.

[0044] like Figure 1-3 As shown, the device for measuring the specific heat capacity of a liquid at constant pressure includes a laser heating system, a temperature measurement system, a pneumatic suspension system, a sample operation system, and a gas composition control system. The laser heating system heats and melts the sample, and the temperature measurement system measures the sample's temperature data under high-temperature conditions. The gas composition control system is connected to the pneumatic suspension system and the sample operation system. The pneumatic suspension system includes a sealed chamber 14, within which is disposed a suspension base 2, a nozzle 1, and a storage table 18. The storage table 18 can store the sample, and the nozzle 1 is mounted on the suspension base 2 for suspending the sample. The sample operation system includes an operating rod 11 for operating the sample to move between the storage table 18 and the nozzle 1. The measuring device can use the nozzle to suspend a spherical sample with a diameter of 2-4 mm and use an infrared two-color thermometer to measure the sample temperature. The measurement process is non-contact, which can prevent the measured liquid from reacting with the container material at high temperatures.

[0045] like Figure 2 As shown, the pneumatic suspension system's suspension base 2 is threaded at the top and connected to the nozzle 1. The bottom is connected to a bracket 3, which is fixed to an optical platform 4 to ensure the stability of the suspension base 2. The bottom of the suspension base 2 is equipped with a ZnSe glass bottom laser transmission window 24, which allows the laser beam to pass through and then be focused to the bottom of the spherical sample through the throat of the nozzle 1. The bottom of the suspension base 2 is reserved for a gas inlet 5, a cooling water inlet 6, and a cooling water outlet 7. The gas inlet 5 is connected to a first gas source 25, with the gas flow controlled by a flow controller 26. An angle valve 27 is used to control the opening and closing of the gas circuit. The inert gas is passed to the gas inlet 5, stably suspending spherical samples with a diameter of 2-4 mm above the nozzle 1, preventing contact reactions between the sample and the nozzle 1 under high temperature conditions. The cooling water inlet 6 and cooling water outlet 7 are connected to an external chiller, which continuously supplies cooling water to the cooling water loop 21 through a water circulation system, thereby cooling the suspension base 2 and the nozzle 1 and preventing the nozzle 1 from melting under high temperature conditions.

[0046] The measuring device also includes a temperature controller and a sample monitoring system. The temperature controller receives temperature data and fits the temperature data to obtain the constant-pressure specific heat capacity. The temperature measurement system uses two infrared two-color thermometers 10 to measure the sample temperature and can record the temperature data of the sample's rapid cooling process. One infrared two-color thermometer 10 has a range of 900-1800°C, and the other has a range of 1600-3300°C. The two infrared two-color thermometers 10 are connected to a temperature controller, which intelligently integrates and outputs the temperature output data of the two infrared two-color thermometers 10 to achieve temperature measurement in the range of 900-3300°C, taking into account the characteristics of high measurement accuracy and wide temperature measurement range; the temperature measurement method is non-contact, which can avoid contact contamination of high-temperature samples.

[0047] The sample monitoring system includes a high-speed camera 13 and a macro zoom lens, located on the side of the suspension base 2, to monitor the sample's suspension status. The macro zoom lens has a magnification of 1.4-14.4, and a bandpass filter can be installed in front of the macro lens. During experiments, the magnification can be adjusted according to the sample size to ensure that the sample occupies a major portion of the high-speed camera's field of view, allowing the high-temperature self-luminous sample to be clearly imaged on the high-speed camera. The sample's position in the image can be used to determine whether the suspension is stable. If the sample's luminous intensity is too high, a bandpass filter can be installed in front of the macro zoom lens to filter out some visible light and prevent overexposure.

[0048] The gas composition control system includes a pump, a first gas source 25, and a second gas source 40. The pump is used to extract gas from the sealed chamber 14. The first gas source 25 is connected to the suspension base 2, providing gas to the pneumatic suspension system and maintaining a constant pressure within the sealed chamber 14. The second gas source 40 is connected to the operating rod 11 to adjust the pressure within the operating rod 11. The pump includes a dry pump 31 and a molecular pump 32, which are connected to the sealed chamber 14 to extract impurity gases from the sealed chamber 14. The gas composition control system uses the dry pump 31 and the molecular pump 32 to control the gas composition within the sealed chamber 14.

[0049] like Figure 6 As shown, the gas component control system also includes a first gas supply branch and a second gas supply branch. The first gas source 25 can be selectively connected to the first gas supply branch or the second gas supply branch; the first gas supply branch includes a first high-pressure gas tank 37 and a first pressure reducing valve 38, and the second gas supply branch includes a second high-pressure gas tank 42 and a second pressure reducing valve 43; the first high-pressure gas tank 37 contains a first inert gas, and the second high-pressure gas tank 42 contains a second inert gas. The first gas supply branch and the second gas supply branch are connected to the first gas source 25 of the downstream pipeline using a three-way connector 39. The first high-pressure gas tank 37 and the second high-pressure gas tank 42 store different types of gases. During the experiment, the required branch can be opened according to the required gas components; the above-mentioned pneumatic suspension method has few restrictions on the material to be measured, so the measurement object is suitable for metal and non-metal materials.

[0050] The gas composition control system is based on the sealed chamber 14. Figures 1-4 As shown. The sealed chamber 14 houses the suspension base 2 and the storage platform 18. One side is connected to the sealing bellows 12 and has an exhaust port 15. The other three sides have side windows 23. The top is connected to a purge 16 and has a top laser transmission window 19, a temperature measurement window 20, and a storage platform window 22. Except for the top laser transmission window 19, which is made of ZnSe glass, the other windows can be made of quartz glass. The exhaust port 15 is connected to a filter 28, which is then connected to a dry pump 31. An angle valve 27 is used to control the opening and closing of the gas circuit. The exhaust port 15 has two bypasses. One is connected to the angle valve 27 and the molecular pump 32, which is then connected to the dry pump 31. The other is connected to the pressure relief valve 30. The sealed chamber 14 is also provided with a top laser transmission window 19 and a purge 16. The top laser transmission window 19 is used to transmit the laser light emitted by the laser 8. The purge 16 is arranged adjacent to the top laser transmission window 19 to prevent the sample from volatilizing and depositing on the top laser transmission window 19.

[0051] The operating rod 11 is connected to a dry pump 31, which pumps pressure from the operating rod 11, allowing it to absorb the sample. The operating rod 11 is also connected to a second gas source 40, receiving gas from the second gas source 40 to allow the sample to separate from the operating rod 11. The operating rod 11 is connected to a filter 28, a needle valve 29, an angle valve 27, and the dry pump 31. A bypass is also provided, connecting the angle valve 27 and the second gas source 40.

[0052] The gas composition control system also includes a third gas source 41, which supplies gas to the purge 16. The purge 16 is connected to the angle valve 27, the flow controller 26 and the gas source 25 in sequence, and the opening direction is directly below the top laser transmission window 19. The sealed chamber 14 is connected to the pressure sensor 17 on the side of the high-speed camera 13 to monitor the internal pressure. The vacuum in the sealed chamber 14 can be achieved by evacuating the air through the dry pump 31 and the molecular pump 32 to a maximum vacuum degree of 1e -4 Pa, thereby venting impurities inside, is then filled with inert gas through the gas line to regulate the gas composition within the sealed chamber 14. Supplying gas to the purge 16 prevents volatilization of the high-temperature sample from depositing on the top laser transmission window 19, reducing the risk of ZnSe lens failure. Installing a filter 28 prevents volatile substances from diffusing outside the sealed chamber 14.

[0053] The sample handling system includes an operating rod 11, a sealing bellows 12, and a storage platform 18. The storage platform 18 is arranged on one side of the suspension base 2 and includes six cylindrical recesses. The operating rod 11 is an L-shaped circular tube structure, embedded in the sealing bellows 12. The front end is a detachable nozzle 35 with a conical surface, which is threaded with the operating rod body 34. Figure 5As shown. The nozzle opening diameter ranges from 1.5-2.5mm, and the inner wall surface is provided with a groove 36. By pumping air into and out of the tail end of the operating rod 11, the spherical sample can be picked up and released at the detachable nozzle 35, realizing the transfer of the sample between the storage table 18 and the nozzle 1. During the experiment, different sizes of detachable nozzles 35 can be used according to the size of the sample. The groove 36 on the inner wall surface prevents the spherical sample from getting stuck due to the pressure difference between the inside and outside of the operating rod 11. The storage table 18 can store six spherical samples at a time. Therefore, after a single vacuum to remove impurity gases, six experiments can be carried out under the same gas composition conditions, without the need for repeated vacuuming operations, which can improve experimental efficiency.

[0054] The laser heating system includes at least two concave reflectors 9 and at least two lasers 8. The lasers 8 are arranged on the side of the suspension base 2, with concave reflectors 9 positioned above and below the nozzle 1 in the direction of gas flow. The laser heating system uses two lasers 8 to heat and melt the sample. Both lasers 8 are arranged on the side of the suspension base 2, in an up-and-down arrangement. The two concave reflectors 9 are mounted directly above and below the nozzle 1, respectively, with the concave reflectors 9 and the light outlets of the lasers 8 located at the same horizontal plane. The laser beams emitted by the two lasers 8 are reflected by the two concave reflectors 9 and focused onto the upper and lower surfaces of the sample, forming a light spot with a diameter of 1-2 mm. Due to the high power density of the laser heating method, sample temperatures exceeding 3000°C can be easily achieved, and both metal and non-metallic materials can be heated and melted into liquids.

[0055] The gas component control system also includes a speaker 33, which is arranged on the air inlet pipe below the suspension base 2. The sound waves generated by the speaker 33 can be transmitted to the sample along the air inlet pipe, and can force the high-temperature sample to vibrate. According to the image analysis method and the droplet vibration method, the density, surface tension and viscosity of the high-temperature liquid can be measured.

[0056] When using the above-mentioned measuring device to measure the constant-pressure specific heat capacity of a liquid, the following steps are included: a sample loading step S1: loading the sample onto the storage table 18; a vacuuming step S2: vacuuming the sealed chamber 14 using a dry pump 31 and a molecular pump 32; a filling inert gas step S3: filling the sealed chamber 14 with the first inert gas or the second inert gas from the first gas source 25; a sample suspension step S4: using the operating rod 11 to transfer the sample from the storage table 18 to the nozzle 1, opening the first gas source 25 to suspend the sample through the inert gas; a sample heating and melting step S5: using the laser 8 to heat and melt the sample, reaching a specified temperature and waiting for the temperature to stabilize, turning off the laser 8, and simultaneously using the infrared two-color thermometer 10 to record the temperature data of the sample during the rapid cooling process.

[0057] Preferably, the measurement method also includes a gas source switching step S6. In step S6, after the sample is cooled, the sample is transferred from the nozzle 1 back to the storage table 18, and the vacuum operation is repeated. Then, the branch of the first gas source 25 is adjusted and switched to another inert gas to obtain temperature data of another set of samples during the rapid cooling process.

[0058] Preferably, the measurement method further includes a data fitting step S7, in which the two sets of temperature data are fitted to obtain the constant-pressure specific heat capacity.

[0059] In summary, from the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0060] 1. Use the nozzle 1 to suspend a spherical sample with a diameter of 2-4 mm, and use the infrared two-color thermometer 10 to measure the sample temperature. The measurement process is non-contact, which can avoid the reaction between the measured liquid and the container material at high temperature;

[0061] 2. Using a more efficient laser heating method, the sample temperature can reach over 3000°C;

[0062] 3. The pneumatic suspension method has little restriction on the material to be measured, and the measurement object is suitable for metal and non-metal materials;

[0063] 4. The sealed chamber uses dry pump 31 and molecular pump 32 to pump air, which can reach 1e -4 The ultimate vacuum degree of Pa level can fully expel the impurity gas in the sealed chamber, prevent the reaction between high temperature samples and impurity gases such as oxygen, and also realize the regulation of gas composition;

[0064] 5. The storage table 18 can store six spherical samples at a time. The L-shaped operating rod and sealed bellows can flexibly transfer the samples between the storage table and the nozzle. Therefore, after one vacuum to remove impurity gases, six experiments can be carried out under the same gas composition conditions without repeated vacuuming, which improves experimental efficiency.

[0065] 6. Both the gas outlets of the exhaust port 15 and the operating rod 11 are connected to filters to prevent volatile materials from escaping outside the sealed chamber. In addition, the purge 16 blows air toward the top laser transmission window 19 to prevent volatile materials from being deposited on the top laser transmission window 19, reducing the risk of failure of the ZnSe lens and improving the applicability of measuring volatile materials.

[0066] 7. The measuring device can be used not only to measure the constant pressure specific heat capacity of high temperature liquid, but also to measure the density, surface tension and viscosity of high temperature liquid. The device has a high degree of integration.

[0067] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A device for measuring the specific heat capacity of a liquid at constant pressure, comprising a laser heating system and a temperature measurement system. The laser heating system heats and melts a sample, and the temperature measurement system measures the temperature data of the sample under high temperature conditions. The measuring device further comprises: A pneumatic suspension system, comprising a sealed chamber (14), wherein a suspension base (2), a nozzle (1) and a storage table (18) are arranged in the sealed chamber (14), wherein the storage table (18) can store the sample, and the nozzle (1) is mounted on the suspension base (2), and the nozzle (1) is used to suspend the sample; A sample operating system, comprising an operating rod (11), wherein the operating rod (11) is used to operate the sample to move between the storage table (18) and the nozzle (1); A gas component control system is connected to the pneumatic suspension system and the sample operation system.

2. The measuring device according to claim 1, characterized in that The gas component control system comprises a pump, a first gas source (25) and a second gas source (40), wherein the pump is used to extract gas from the sealed chamber (14); the first gas source (25) is connected to the suspension base (2) to provide gas for the pneumatic suspension system and to keep the pressure in the sealed chamber (14) constant; and the second gas source (40) is connected to the operating rod (11) to adjust the pressure inside the operating rod (11).

3. The measuring device according to claim 2, characterized in that The gas component control system includes a first gas supply branch and a second gas supply branch, and the first gas source (25) can be selectively connected to the first gas supply branch or the second gas supply branch; the first gas supply branch includes a first high-pressure gas tank (37) and a first pressure reducing valve (38), and the second gas supply branch includes a second high-pressure gas tank (42) and a second pressure reducing valve (43); the first high-pressure gas tank (37) contains a first inert gas, and the second high-pressure gas tank (42) contains a second inert gas.

4. The measuring device according to claim 1, characterized in that The measuring device further includes a temperature measurement controller, which receives the temperature data and fits the temperature data to obtain the constant-pressure specific heat capacity.

5. The measuring device according to claim 1, characterized in that The measuring device further comprises a sample monitoring system, wherein the sample monitoring system comprises a high-speed camera (13) capable of monitoring the suspension state of the sample.

6. The measuring device according to claim 3, characterized in that The pump comprises a dry pump (31) and a molecular pump (32), and the dry pump (31) and the molecular pump (32) are in communication with the sealed chamber (14) to extract impurity gas from the sealed chamber (14).

7. The measuring device according to claim 6, characterized in that The operating rod (11) is connected to the dry pump (31), and the dry pump (31) draws the internal pressure of the operating rod (11), so that the operating rod (11) can adsorb the sample; the operating rod (11) is also connected to the second gas source (40), receiving gas from the second gas source (40), so that the sample can be separated from the operating rod (11).

8. The measuring device according to claim 1, characterized in that The laser heating system comprises at least two concave reflectors (9) and at least two lasers (8), wherein the lasers (8) are arranged on the side of the suspension base (2), and the concave reflectors (9) are respectively arranged above and below the gas flow direction of the nozzle (1).

9. The measuring device according to claim 8, characterized in that The sealed chamber (14) is further provided with a top laser transmission window (19) and a purge (16). The top laser transmission window (19) is used to transmit the laser light emitted by the laser (8). The purge (16) is arranged adjacent to the top laser transmission window (19) to prevent the sample from volatilizing and being deposited on the top laser transmission window (19).

10. The measuring device according to claim 9, characterized in that The gas component control system further comprises a third gas source (41), and the third gas source (41) supplies gas to the purge device (16).

11. The measuring device according to claim 10, characterized in that The gas component control system further comprises a speaker (33), wherein the speaker (33) is arranged on the air inlet pipe below the suspension base (2), and the sound waves generated by the speaker (33) can be transmitted to the sample along the air inlet pipe.

12. The measuring device according to claim 11, characterized in that The temperature measurement system comprises an infrared two-color thermometer (10) capable of recording temperature data of the sample during the rapid cooling process.

13. A method for measuring the specific heat capacity of a liquid at constant pressure, using the measuring device according to any one of claims 1 to 12, characterized in that: The steps include: Sample loading step S1: loading the sample onto the storage station (18); Vacuuming step S2: evacuating the sealed chamber (14) using a dry pump (31) and a molecular pump (32); Filling inert gas step S3: filling the sealed chamber (14) with the first inert gas or the second inert gas from the first gas source (25); Sample suspension step S4: using the operating rod (11) to transfer the sample from the storage table (18) to the nozzle (1), opening the first gas source (25) to pass inert gas to suspend the sample; Sample heating and melting step S5: using the laser (8) to heat and melt the sample, and after reaching a specified temperature and the temperature is stabilized, turning off the laser (8) and simultaneously using an infrared two-color thermometer (10) to record the temperature data of the sample's rapid cooling process.

14. The measuring method according to claim 13, characterized in that: The measurement method further includes a gas source switching step S6. In the step S6, after the sample is cooled, the sample is transferred from the nozzle (1) back to the storage table (18), and the vacuum operation is repeated. Then, the branch of the first gas source (25) is adjusted and switched to another inert gas to obtain another set of temperature data of the sample's rapid cooling process.

15. The measuring method according to claim 14, characterized in that The measurement method further includes a data fitting step S7, in which two sets of temperature data are fitted to obtain the constant-pressure specific heat capacity.

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