A device and method for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia

Abstract

The present invention relates to a device and method for testing the heat and mass transfer characteristics and laws of micro-droplets absorbing ammonia, comprising a mixed gas preparation system, a droplet preparation system, a high-speed camera system, and a sample tank test system, wherein the sample tank test system comprises an observation chamber, a supporting substrate, and a heating substrate, wherein the supporting substrate is arranged on the heating substrate; the mixed gas preparation system comprises a gas mixer, wherein the gas mixer is connected to an ammonia bottle, a dry air bottle, and a humidifier, and the gas mixer is connected to the observation chamber; the droplet preparation system comprises a micro-liquid inlet, a micro-injection pump for driving the micro-liquid inlet to produce droplets, and the micro-liquid inlet is connected to the observation chamber; the high-speed camera system is used for high-speed shooting of the microscopic characteristics and transient evolution process of water droplets absorbing ammonia on the supporting substrate. The design is reasonable, and the microscopic behavior characteristics such as the morphological changes and concentration distribution of water droplets absorbing ammonia on the heating substrate can be accurately captured, and a scientific basis is provided for revealing the mechanism of droplet absorption of ammonia and designing a new type of high-efficiency water curtain spraying system.

Description

Technical field:

[0002] The invention belongs to the technical field of multiphase flow and heat and mass transfer, and relates to a device and method for testing heat and mass transfer characteristic laws of micro-droplet absorption of ammonia. Background technology:

[0004] Liquid ammonia storage and transportation equipment may leak due to aging and corrosion of valves, flanges and other equipment, improper operation of personnel, etc. Ammonia is toxic and explosive. In order to reduce the casualties that may be caused by the leakage and spread of ammonia, most of the storage tanks and other facilities in my country currently use water curtain spraying to reduce the consequences of accidents.

[0005] Water curtain spray technology uses tiny droplets atomized by water curtain nozzles to increase the gas-liquid contact area, dilute the ammonia concentration and hinder the diffusion of ammonia clouds. Its basic principle is that due to the physical property of ammonia being easily soluble in water, a certain droplet temperature, droplet particle size, water curtain nozzle type and installation angle are usually used to improve the water curtain absorption efficiency.

[0006] Chinese patent publication number CN108225981A discloses a prediction model for the distribution of ammonia concentration diluted by a water curtain, which takes into account the mass transfer of ammonia absorbed by water curtain droplets. Based on the double-membrane mass transfer theory, a theoretical model of ammonia absorbed by water curtain droplets is established, which can accurately predict the concentration of ammonia diluted by water curtain in the downwind direction. Chinese patent publication number CN114949702A discloses a fire water curtain spray system and spray method for treating liquid ammonia leakage. A bottom valve is set at the bottom of the water suction pipe, and water is sent into the water collection tank through siphon action. In order to avoid the defect of incomplete closure of the upper part when spraying from top to bottom, a bottom-up spraying method is adopted to prevent ammonia from escaping. The pipeline adopts a ring network layout, and multiple nozzles are installed to form a covering water curtain, which can effectively inhibit the diffusion of ammonia.

[0007] The changes in substrate wettability, temperature and other parameters and the properties of the mixed gas have a significant impact on the morphological changes and concentration distribution of water droplets when absorbing ammonia, changing the flow velocity, flow direction and temperature distribution inside the water droplets, thereby affecting the absorption efficiency of the water curtain. Studying the microscopic characteristics and transient evolution of ammonia absorption by water droplets on a heated substrate helps to reveal the mechanism of ammonia absorption by droplets, determine the optimal absorption conditions, and provide a basis for designing a new type of efficient water curtain spray system.

[0008] Therefore, it is necessary to develop a device and method for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia, which can be used to study the morphological changes and concentration distribution characteristics of water droplets absorbing ammonia on a heated substrate, as well as the influence of mixed gas properties and substrate wettability, temperature and other parameters on the process of water droplets absorbing ammonia, so as to lay a theoretical foundation for the development of efficient water curtain spraying technology and the inhibition of liquid ammonia leakage and diffusion. Summary of the invention:

[0010] The purpose of the present invention is to provide a testing device for the heat and mass transfer characteristics of micro-droplets absorbing ammonia. The device has a reasonable design and can be used to study the influence of mixed gas properties and substrate wettability, temperature and other parameters on the process of water droplets absorbing ammonia. The test results can provide microscopic dynamics theory and basic data for the design and optimization of water curtain spray systems.

[0011] A method for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia is also provided. The method can synchronously record the transient evolution process of the microscopic characteristics of water droplets and the concentration distribution inside the water droplets, providing an experimental basis for in-depth analysis of the microscopic characteristics of ammonia absorption by water droplets on a heated substrate and its transient evolution process.

[0012] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present invention is: a device for testing the heat and mass transfer characteristics and laws of micro-droplet absorption of ammonia, comprising a mixed gas preparation system, a droplet preparation system, a high-speed camera system and a sample tank test system, wherein the sample tank test system comprises an observation chamber, a supporting substrate and a heating substrate arranged inside the observation chamber, and the supporting substrate is arranged on the heating substrate; the mixed gas preparation system comprises a gas mixer, the input end of the gas mixer is connected to an ammonia bottle, a dry air bottle and a humidifier, and the output end of the gas mixer is connected to the gas input end of the observation chamber; the droplet preparation system comprises a micro-liquid feeder and a micro-injection pump for driving the micro-liquid feeder to produce droplets, and the output end of the micro-liquid feeder is connected to the droplet input end at the top of the observation chamber; the high-speed camera system is used to shoot the microscopic characteristics and transient evolution process of water droplets absorbing ammonia on the supporting substrate at high speed.

[0013] Furthermore, the mixed gas preparation system also includes a gas monitoring module and an industrial computer. The detection end of the gas monitoring module is arranged at the gas input end of the observation chamber, and is used to detect the flow rate, humidity and concentration of the gas input into the observation chamber. The control end of the gas monitoring module is connected to the industrial computer.

[0014] Furthermore, the mixed gas preparation system also includes a first electric valve, a second electric valve, a third electric valve and a fourth electric valve. The first electric valve, the second electric valve and the third electric valve are respectively arranged at the output ends of the ammonia bottle, the dry air bottle and the humidifier. The fourth electric valve is arranged at the output end of the gas mixer. The control ends of the first electric valve, the second electric valve, the third electric valve and the fourth electric valve are all connected to the industrial computer.

[0015] Furthermore, it also includes a purging system, which includes a nitrogen bottle and a fifth electric valve, the output end of the nitrogen bottle is connected to the input end of the gas mixer; the fifth electric valve is arranged at the output end of the nitrogen bottle, and the control end of the fifth electric valve is connected to the industrial computer.

[0016] Furthermore, the microinjection pump is connected to an industrial computer.

[0017] Furthermore, the sample slot testing system also includes a PID temperature controller, which is connected to the heating substrate and is used to adjust the heating temperature of the heating substrate.

[0018] Furthermore, the sample tank testing system also includes an exhaust gas treatment tank with acid liquid added inside, the input end of the exhaust gas treatment tank is connected to the gas output end of the observation chamber, and a sixth electric valve is installed between the two, and the sixth electric valve is connected to the industrial computer.

[0019] Furthermore, the high-speed camera system includes a high-speed camera and a laser generator distributed on both sides of the observation room, the high-speed camera and the laser generator both correspond to the position of the supporting substrate, the laser generator provides laser for inducing fluorescence, the high-speed camera is connected to a high-power lens, and the high-power lens is connected to a filter.

[0020] Furthermore, the high-speed camera system also includes an image acquisition computer, which is connected to the high-speed camera and is used to store and analyze photos taken by the high-speed camera.

[0021] Another technical solution adopted by the present invention is: a method for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia, comprising the following steps:

[0022] Step S1: prepare a solution using deionized water and a fluorescent agent, and take a sample using a micro-injector;

[0023] Step S2: Turn on the high-speed camera, laser generator, PID temperature controller, image acquisition computer and industrial computer;

[0024] Step S3: Open the fourth electric valve, the fifth electric valve and the sixth electric valve to purge the entire system with nitrogen;

[0025] Step S4: closing the fifth electric valve, opening the first electric valve, the second electric valve and the third electric valve, adjusting the flow rate, concentration and humidity of the mixed gas output by the gas mixer according to the experimental requirements, and adjusting the heating temperature of the heating substrate by the PID temperature controller;

[0026] Step S5: using an industrial computer to control a micro-injection pump to push a micro-liquid inlet device to generate droplets;

[0027] Step S6: The image acquisition computer acquires microscopic features such as morphological changes and concentration distribution of the water droplets on the supporting substrate when absorbing ammonia;

[0028] Step S7: closing the first electric valve, the second electric valve, and the third electric valve, and opening the fifth electric valve to purge the entire system with nitrogen;

[0029] Step S8: Change the properties of the mixed gas and the wettability and temperature parameters of the supporting substrate, repeat steps S4-S7, and study the influence of the properties of the mixed gas and the wettability and temperature parameters of the supporting substrate on the microscopic characteristics and transient evolution process of the water droplets on the supporting substrate when absorbing ammonia.

[0030] Compared with the prior art, the present invention has the following effects: the present invention utilizes a combination of high-speed video and optical magnification to accurately capture microscopic features such as morphological changes of water droplets on a substrate when absorbing ammonia and its transient evolution process, and provides a data basis for the design of a water curtain spray system and the optimization of working parameters; the substrate heating temperature is precisely adjusted by a PID temperature controller, and the influence of the heating temperature on the microscopic features of water droplets on a substrate when absorbing ammonia can be accurately evaluated; the laser induced fluorescence technology can be used to solve the problem of observing the transient evolution law of the internal concentration distribution of the droplets; the opening of the electric valve is adjusted by an industrial computer, and the influence of the properties of the mixed gas on the microscopic features such as the morphological changes of water droplets on the substrate, the internal concentration distribution of water droplets and their transient evolution law can be accurately analyzed, and the process is simple, the operation is simple, and the research parameters can be easily changed. Description of the drawings:

[0032] Figure 1 It is a schematic diagram of the structure of an embodiment of the present invention.

[0033] In the figure:

[0034] 1- ammonia bottle; 2- dry air bottle; 3- nitrogen bottle; 4- humidifier; 5- fifth electric valve; 6- first electric valve; 7- second electric valve; 8- third electric valve; 9- gas mixer; 10- fourth electric valve; 11- image acquisition computer; 12- high-speed camera; 13- high-power lens; 14- filter; 15- PID temperature controller; 16- supporting substrate; 17- heating substrate; 18- sixth electric valve; 19- tail gas treatment tank; 20- observation room; 21- laser generator; 22- gas monitoring module; 23- micro-injection pump; 24- micro-liquid inlet; 25- industrial computer. Specific implementation method:

[0036] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0038] like Figure 1 As shown, a device for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia gas in the present invention comprises a mixed gas preparation system, a droplet preparation system, a high-speed camera system, a sample tank test system and a purge system.

[0039] The mixed gas preparation system includes a gas mixer 9, an ammonia bottle 1, a dry air bottle 2, a humidifier 4, a gas monitoring module 22, an industrial computer 25, a first electric valve 6, a second electric valve 7, a third electric valve 8 and a fourth electric valve 10. The first electric valve 6, the second electric valve 7 and the third electric valve 8 are respectively arranged at the output ends of the ammonia bottle 1, the dry air bottle 2 and the humidifier 4. The first electric valve 6, the second electric valve 7 and the third electric valve 8 are all connected to the industrial computer 25. The opening of the electric valve is adjusted by the industrial computer 25 to obtain ammonia with different concentrations and different humidity. The input end of the gas mixer 9 is connected to the output ends of the ammonia bottle 1, the dry air bottle 2 and the humidifier 4. The ammonia output from the ammonia bottle 1, the air output from the dry air bottle 2 and the water vapor output from the humidifier 4 are mixed inside the gas mixer 9 and sent to the sample tank test system after being mixed evenly. The fourth electric valve 10 is arranged at the output end of the gas mixer 9. The control end of the fourth electric valve 10 is connected to the industrial computer 25. The opening of the fourth electric valve 10 is adjusted by the industrial computer 25 to control the flow rate of the mixed gas. The gas monitoring module 22 is connected to the industrial computer 25 and is used to detect the flow rate, humidity and concentration of the gas entering the sample tank test system.

[0040] The droplet preparation system includes a micro-liquid injector 24, a micro-injection pump 23 for driving the micro-liquid injector 24 to generate droplets, and an output end of the micro-liquid injector 24 and a sample tank test system so as to transport droplets to the sample tank test system.

[0041] The sample tank test system includes an observation chamber 20, a PID temperature controller 15, a bearing substrate 16, a heating substrate 17, a sixth electric valve 18, and an exhaust gas treatment tank 19. Among them, the output end of the gas mixer 9 is connected to the gas input end of the observation chamber 20, the output end of the micro-liquid inlet 24 is connected to the droplet input end at the top of the observation chamber 20, and the detection end of the gas monitoring module 22 is arranged at the gas input end of the observation chamber 20. The bearing substrate 16 and the heating substrate 17 are both arranged inside the observation chamber 20, and the heating substrate 17 is arranged on the bottom surface inside the observation chamber 20. The bearing substrate 16 is adhered to the heating substrate 17, and the wettability can be changed by replacing different substrates. The PID temperature controller 15 is connected to the heating substrate 17 and is used to adjust the heating temperature of the heating substrate. The input end of the exhaust gas treatment tank 19 is connected to the gas output end of the observation chamber 20, and a sixth electric valve 18 is installed between the two. The sixth electric valve 18 is connected to the industrial computer 25. Acid is added to the exhaust gas treatment tank 19 to treat the exhaust gas generated by the experiment.

[0042] The high-speed camera system includes a high-speed camera 12, a high-power lens 13, a filter 14, an image acquisition computer 11, and a laser generator 21. The high-speed camera 12 and the laser generator 21 are distributed on both sides of the observation room 20. The high-speed camera 12 and the laser generator 21 are both corresponding to the position of the supporting substrate 16. The laser generator 21 provides laser light for inducing fluorescence. The high-speed camera 12 is connected to the high-power lens 13 to shoot the microscopic characteristics and transient evolution process of water droplets absorbing ammonia on the supporting substrate at high speed. The high-power lens 13 is connected to the filter 14 to selectively absorb specific excitation fluorescence. The image acquisition computer 11 is connected to the high-speed camera 12 to store and analyze the photos taken by the high-speed camera.

[0043] The purge system includes a nitrogen bottle 3 and a fifth electric valve 5. The output end of the nitrogen bottle 3 is connected to the input end of the gas mixer 9. The fifth electric valve 5 is arranged at the output end of the nitrogen bottle 3. The control end of the fifth electric valve 5 is connected to the industrial computer 25. The fifth electric valve 5 is opened and closed by the industrial computer 25 to purge the entire experimental system.

[0044] In this embodiment, in the droplet preparation system, the micro-injection pump 23 is connected to the industrial computer 25, and the size of the droplet is controlled by the micro-injection pump 23 connected to the industrial computer 25, that is, the micro-injection pump 23 is used to adjust the micro-liquid inlet 24 to adjust the droplet size.

[0045] In this embodiment, in a high-speed camera system, laser induced fluorescence technology is used to observe the concentration distribution inside the droplet.

[0046] In this embodiment, the working process is as follows: first, a solution of a certain proportion is prepared using deionized water and a fluorescent agent, and a micro-liquid inlet 24 is used to take a sample. The high-speed camera 12, the laser generator 21, the PID temperature controller 15, the image acquisition computer 11 and the industrial computer 25 are turned on. The fourth electric valve 10, the fifth electric valve 5 and the sixth electric valve 18 are opened, and the entire system is purged with nitrogen. After the purging is completed, the fifth electric valve 5 is closed, and the first electric valve 6, the second electric valve 7 and the third electric valve 8 are opened. The industrial computer 25 is used to adjust the first electric valve 6, the second electric valve 7 and the third electric valve 8 according to the experimental requirements to obtain ammonia with a certain concentration and humidity, and the fourth electric valve 10 is adjusted to obtain a mixed gas with a certain flow rate. The flow rate, humidity and concentration of the mixed gas are detected by the gas monitoring module 22, and the substrate temperature required by the experiment is adjusted by the PID temperature controller 15. When the flow rate, concentration and humidity of the mixed gas meet the experimental conditions, the industrial computer 25 is used to control the micro-injection pump 23 to push the micro-liquid inlet 24 to generate droplets. The image acquisition computer 11 acquires microscopic features such as the morphological changes and concentration distribution of the water droplets on the supporting substrate 16 when absorbing ammonia. The first electric valve 6, the second electric valve 7, and the third electric valve 8 are closed, and the fifth electric valve 5 is opened to purge the entire system with nitrogen. After the purge is completed, the fifth electric valve 5 is closed. By changing the properties of the mixed gas and the parameters such as the wettability and temperature of the substrate, and repeating the above test process, the effects of the properties of the mixed gas and the parameters such as the wettability and temperature of the substrate on the microscopic features such as the morphological changes and concentration distribution of the water droplets on the heated substrate when absorbing ammonia and their transient evolution process can be evaluated.

[0047] The basic principle of the present invention is to use laser to induce concentration-sensitive fluorescent agents to produce light of different intensities based on the property that ammonia is easily soluble in water, and obtain the concentration distribution inside the water droplets during the absorption of ammonia through the calibrated relationship between concentration and light intensity. Based on high-speed camera technology, optical amplification technology, and laser-induced fluorescence technology, the microscopic characteristics such as morphological changes and concentration distribution of water droplets on heated substrates when absorbing ammonia are studied, and the evolution law of its microscopic characteristics is obtained.

[0048] The present invention provides a method for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia, comprising the following steps:

[0049] Step S1: prepare a solution using deionized water and a fluorescent agent, and take a sample using a micro-liquid injector 23;

[0050] Step S2: Turn on the high-speed camera 12, the laser generator 21, the PID temperature controller 15, the image acquisition computer 11 and the industrial computer 25;

[0051] Step S3: Open the fourth electric valve 10, the fifth electric valve 5 and the sixth electric valve 18 to purge the entire system with nitrogen;

[0052] Step S4: close the fifth electric valve 5, open the first electric valve 6, the second electric valve 7 and the third electric valve 8, adjust the flow rate, concentration and humidity of the mixed gas output by the gas mixer 9 according to the experimental requirements, and adjust the heating temperature of the heating substrate 17 through the PID temperature controller 15;

[0053] Step S5: using the industrial computer 25 to control the micro-injection pump 23 to push the micro-liquid inlet 24 to generate droplets;

[0054] Step S6: The image acquisition computer 11 acquires microscopic features such as morphological changes and concentration distribution of the water droplets on the supporting substrate 16 when the water droplets absorb ammonia gas;

[0055] Step S7: close the first electric valve 6, the second electric valve 7, and the third electric valve 8, and open the fifth electric valve 5 to purge the entire system with nitrogen;

[0056] Step S8: Change the properties of the mixed gas and the wettability and temperature parameters of the supporting substrate, repeat steps S4-S7, and study the influence of the properties of the mixed gas and the wettability and temperature parameters of the supporting substrate on the microscopic characteristics and transient evolution process of the water droplets on the supporting substrate when absorbing ammonia.

[0057] The advantages of the present invention are: it has the advantages of simple process, easy operation, and easy to change research parameters; by using high-speed camera technology and optical magnification technology, it can accurately capture the microscopic characteristics such as the morphological changes of water droplets on the heated substrate when absorbing ammonia and its transient evolution process, providing a data basis for the design of the water curtain spray system and the optimization of working parameters. By accurately adjusting the substrate heating temperature through the PID temperature controller, the influence of the heating temperature on the microscopic characteristics of the water droplets on the substrate when absorbing ammonia can be accurately evaluated; by using laser induced fluorescence technology, the problem of observing the transient evolution law of the internal concentration distribution of the droplets can be solved. By adjusting the opening of the electric valve by an industrial computer, the influence of the properties of the mixed gas on the microscopic characteristics such as the morphological changes of the water droplets on the substrate, the internal concentration distribution of the water droplets and their transient evolution law can be accurately analyzed.

[0058] If the present invention discloses or involves components or structures that are fixedly connected to each other, then, unless otherwise stated, the fixed connection can be understood as: a detachable fixed connection (for example, connection using bolts or screws), and can also be understood as: a non-detachable fixed connection (for example, riveting, welding). Of course, the mutual fixed connection can also be replaced by an integrated structure (for example, manufactured by integrated molding using a casting process) (except when it is obviously impossible to use an integrated molding process).

[0059] In addition, unless otherwise stated, the terms used to indicate positional relationships or shapes in any of the technical solutions disclosed in the present invention include states or shapes that are approximate, similar, or close to them.

[0060] Any component provided by the present invention may be assembled from a plurality of separate components, or may be a separate component manufactured by an integral forming process.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention, which should be included in the scope of the technical solution for protection of the present invention.

Claims

1. A device for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia, characterized by: It comprises a mixed gas preparation system, a droplet preparation system, a high-speed camera system and a sample tank test system, wherein the sample tank test system comprises an observation chamber, a supporting substrate and a heating substrate arranged inside the observation chamber, wherein the supporting substrate is arranged on the heating substrate; the mixed gas preparation system comprises a gas mixer, wherein the input end of the gas mixer is connected to an ammonia bottle, a dry air bottle and a humidifier, and the output end of the gas mixer is connected to the gas input end of the observation chamber; the droplet preparation system comprises a micro-liquid inlet and a micro-injection pump for driving the micro-liquid inlet to produce droplets, wherein the output end of the micro-liquid inlet is connected to the droplet input end at the top of the observation chamber; the high-speed camera system is used for high-speed photographing the microscopic characteristics and transient evolution process of water droplets absorbing ammonia on the supporting substrate; The mixed gas preparation system also includes a gas monitoring module and an industrial computer. The detection end of the gas monitoring module is arranged at the gas input end of the observation chamber, and is used to detect the flow rate, humidity and concentration of the gas input into the observation chamber. The control end of the gas monitoring module is connected to the industrial computer. The sample slot testing system also includes a PID temperature controller, which is connected to the heating substrate and is used to adjust the heating temperature of the heating substrate.

2. The device for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia according to claim 1, characterized in that: The mixed gas preparation system also includes a first electric valve, a second electric valve, a third electric valve and a fourth electric valve. The first electric valve, the second electric valve and the third electric valve are respectively arranged at the output ends of the ammonia bottle, the dry air bottle and the humidifier. The fourth electric valve is arranged at the output end of the gas mixer. The control ends of the first electric valve, the second electric valve, the third electric valve and the fourth electric valve are all connected to the industrial computer.

3. The device for testing the heat and mass transfer characteristics of micro-droplet absorption of ammonia according to claim 1, characterized in that: It also includes a purging system, which includes a nitrogen bottle and a fifth electric valve. The output end of the nitrogen bottle is connected to the input end of the gas mixer; the fifth electric valve is arranged at the output end of the nitrogen bottle, and the control end of the fifth electric valve is connected to the industrial computer.

4. The device for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia according to claim 1, characterized in that: The microinjection pump is connected to an industrial computer.

5. The device for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia according to claim 1, characterized in that: The sample tank test system also includes an exhaust gas treatment tank with acid liquid added inside. The input end of the exhaust gas treatment tank is connected to the gas output end of the observation chamber, and a sixth electric valve is installed between the two. The sixth electric valve is connected to the industrial computer.

6. The device for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia according to claim 1, characterized in that: The high-speed camera system includes a high-speed camera and a laser generator distributed on both sides of the observation room. The high-speed camera and the laser generator both correspond to the position of the supporting substrate. The laser generator provides laser for inducing fluorescence. The high-speed camera is connected to a high-power lens, and the high-power lens is connected to a filter.

7. The device for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia according to claim 6, characterized in that: The high-speed camera system also includes an image acquisition computer, which is connected to the high-speed camera and is used to store and analyze the photos taken by the high-speed camera.

8. A method for testing the heat and mass transfer characteristics of micro-droplets absorbing ammonia, characterized in that: The method comprises using the device for testing the heat and mass transfer characteristics of ammonia absorption by micro-droplets as claimed in any one of claims 1 to 7, comprising the following steps: Step S1: prepare a solution using deionized water and a fluorescent agent, and take a sample using a micro-injector; Step S2: Turn on the high-speed camera, laser generator, PID temperature controller, image acquisition computer and industrial computer; Step S3: Open the fourth electric valve, the fifth electric valve and the sixth electric valve to purge the entire system with nitrogen; Step S4: closing the fifth electric valve, opening the first electric valve, the second electric valve and the third electric valve, adjusting the flow rate, concentration and humidity of the mixed gas output by the gas mixer according to the experimental requirements, and adjusting the heating temperature of the heating substrate by the PID temperature controller; Step S5: using an industrial computer to control a micro-injection pump to push a micro-liquid inlet device to generate droplets; Step S6: The image acquisition computer acquires microscopic features such as morphological changes and concentration distribution of the water droplets on the supporting substrate when absorbing ammonia; Step S7: closing the first electric valve, the second electric valve, and the third electric valve, and opening the fifth electric valve to purge the entire system with nitrogen; Step S8: Change the properties of the mixed gas and the wettability and temperature parameters of the supporting substrate, repeat steps S4-S7, and study the influence of the properties of the mixed gas and the wettability and temperature parameters of the supporting substrate on the microscopic characteristics and transient evolution process of the water droplets on the supporting substrate when absorbing ammonia.

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