Device and method for measuring thickness of foam film by fluorescence method

Abstract

The invention discloses a device for measuring the thickness of a foam film by a fluorescence method, which comprises a constant-temperature and constant-humidity cabinet, a water bath heating table, a foam solution container, a pulse laser transmitter, a film mechanism and a high-speed camera, and the water bath heating table is arranged in the constant-temperature and constant-humidity cabinet in a liftable manner; the foam solution container is used for containing a foam solution and is placed on the water bath heating table; the pulse laser transmitter is mounted in the constant-temperature and constant-humidity cabinet and is used for transmitting monochromatic light with set wavelength and intensity; the film mechanism is slidably arranged in the constant-temperature and constant-humidity cabinet and comprises a film frame, and the film frame is used for forming a foam film; the high-speed camera is slidably arranged in the constant-temperature and constant-humidity cabinet. According to the device for measuring the thickness of the foam film through the fluorescence method, the change of the thickness of the foam film along with time can be accurately measured, the precision of a test result is higher, the repeatability of measurement is high, and the application range is wide. The invention further provides a method for measuring the thickness of the foam film through the fluorescence method.

Description

Technical Field

[0001] The invention relates to the technical field of fire-fighting foam performance detection, and in particular to a device and method for measuring the thickness of a foam film by a fluorescence method. Background Art

[0002] With the rapid development of economy and technology, fire accidents occur frequently, causing huge losses. Liquid fires are difficult to control in time and effectively once they occur due to their fast spreading speed, high burning intensity, and easy explosion, which often causes serious casualties and property losses. Foam fire extinguishing agents have excellent fire extinguishing effect and anti-reignition performance in extinguishing liquid fires by virtue of their dual effects of cooling and suppression, and are widely used in liquid fires. Foam stability, as an important influencing factor of foam performance, often directly determines the foam fire extinguishing effect and anti-reignition performance.

[0003] The generally accepted theory at this stage is that foam stability is mainly affected by three aspects: bubble coarsening, coalescence, and liquid separation. The liquid separation time of 25% and 50% foam mass is used as a standard and important means to measure foam stability. However, the foam liquid separation time calculated by this method is greatly affected by the external environment and human operation, and the test results have certain deviations and randomness. In addition, this method can only reflect the foam stability performance through the mass and speed of the liquid precipitated from the foam, and cannot directly reflect the stability performance of bubbles and thin films. Therefore, the test results are of low accuracy and poor repeatability, which has certain application limitations for experimental research on foam performance. Summary of the invention

[0004] In view of this, the present invention provides a device for measuring the thickness of a foam film by a fluorescence method, which can accurately measure the change of the thickness of the foam film over time, intuitively reflect the stability of the bubble film, avoid the interference of environmental factors on the measurement, and the test results are more accurate, the measurement repeatability is stronger, and the scope of application is wide.

[0005] The invention also provides a method for measuring the thickness of the foam film by using a fluorescence method.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A device for measuring the thickness of a foam film by a fluorescence method, comprising:

[0008] Constant temperature and humidity cabinet;

[0009] A water bath heating table, which can be raised and lowered and arranged inside the constant temperature and humidity cabinet;

[0010] A foam solution container, used for containing the foam solution, is placed on the water bath heating table;

[0011] A pulse laser transmitter is installed in the constant temperature and humidity cabinet, and is used to emit monochromatic light of set wavelength and intensity;

[0012] A film mechanism is slidably disposed in the cabinet body of the constant temperature and humidity cabinet, and the film mechanism comprises a film frame, and the film frame is used to form a foam film;

[0013] The high-speed camera is slidably arranged in the cabinet of the constant temperature and humidity cabinet.

[0014] Optionally, a slide rail is provided in the cabinet, the slide rail is arranged around the longitudinal section of the cabinet, the film mechanism and the high-speed camera are slidably connected to the slide rail, so that the high-speed camera can vertically shoot the foam film on the film frame;

[0015] The bending position of the slide rail is a track arranged in an arc shape.

[0016] Optionally, the film mechanism comprises:

[0017] A first sliding base, slidably connected to the slide rail;

[0018] A first connecting rod connected to the first sliding base;

[0019] A film frame, rotatably connected to the first connecting rod;

[0020] One end of the first connecting rod is rotatably connected to the film frame, and the other end is fixedly connected to the first sliding base.

[0021] Optionally, the first connecting rod is rotatably connected to the film frame via a ball joint connection structure;

[0022] The ball joint connection structure comprises a ball joint holder and a ball joint, and the ball joint is rotatably connected in a slot of the ball joint holder;

[0023] The ball joint holder is fixedly connected to the first connecting rod, and one end of the ball joint away from the ball joint holder is fixedly connected to the film frame.

[0024] Optionally, the high-speed camera is slidably connected to the slide rail via a second sliding base;

[0025] The high-speed camera is connected to the second sliding base via a second connecting rod, one end of the second connecting rod is fixedly connected to the high-speed camera, and the other end of the second connecting rod is connected to the second sliding base.

[0026] Optionally, a lifting support frame is provided on the bottom plate of the cabinet body of the constant temperature and humidity cabinet, the lifting support frame comprises a lifting frame and a support plate connected to the top of the lifting frame, the lifting frame is a retractable frame structure, the lifting frame is driven to rise and fall by a linear drive device, and the bottom of the lifting frame is fixedly connected to the bottom plate of the constant temperature and humidity cabinet;

[0027] The water bath heating platform is placed on the supporting plate.

[0028] Optionally, the constant temperature and humidity cabinet is provided with a control panel, and the control panel is used to control the temperature and humidity of the internal environment of the cabinet body of the constant temperature and humidity cabinet, the heating temperature of the water bath heating table, and the lifting and lowering of the lifting support frame.

[0029] It can be seen from the above technical scheme that the device for measuring the thickness of the foam film by the fluorescence method provided by the present invention can accurately measure the change of the thickness of the foam film over time by setting a film frame for forming and supporting the foam film, a pulsed laser emitter for emitting monochromatic light of a set wavelength, and a high-speed camera for shooting, which can intuitively reflect the stability of the bubble film and better evaluate the liquid separation characteristics of the foam. The film frame, the pulsed laser emitter, and the high-speed camera are all set in a constant temperature and humidity cabinet. During the observation of the foam film, the test space is relatively closed and the temperature and humidity are kept constant for a long time, which can maximize the avoidance of interference from environmental factors, and the accuracy of the test results is higher. The device for measuring the thickness of the foam film by the fluorescence method of the present invention can adjust the temperature of the foam liquid, and can explore the thickness and morphological changes of different types of foam liquids and liquid films at different temperatures by changing the type of foam liquid, which has application value in the field of fire foam research. The device for measuring the thickness of the foam film by the fluorescence method of the present invention has a simple structure, convenient operation, strong repeatability, can change the temperature and humidity of the environment as needed, and has a wide range of applications.

[0030] The present invention also provides a method for measuring the thickness of a foam film by a fluorescence method, comprising the steps of:

[0031] S1. Mix the fluorescent agent and the foam solution evenly according to a set volume ratio, and pour the mixture into a foam solution container, which is placed on a water bath heating table in a constant temperature and humidity cabinet;

[0032] S2, adjusting the position of the film mechanism so that the film frame of the film mechanism is completely immersed in the test solution in the foam solution container;

[0033] S3, after the film frame stays in the test solution for a preset time, adjust the position of the high-speed camera so that the lens of the high-speed camera can vertically shoot the foam film on the film frame, and turn on the pulse laser emitter;

[0034] S4, adjusting the height of the water bath heating platform so that the film frame is away from the foam solution container, and a foam film is generated on the film frame;

[0035] S5. Recording the change of the fluorescence intensity of each location of the foam film on the film frame over time by the high-speed camera.

[0036] Optionally, step S5 further includes step S6, using software to analyze the fluorescence intensity photos taken by the high-speed camera, obtaining the film thickness corresponding to each fluorescence photo through the fluorescence intensity and film thickness formula obtained by the fluorescence calibration test, and analyzing the change of film thickness distribution over time as an indicator to measure the liquid separation speed of the foam film.

[0037] Optionally, in step S1, the fluorescent agent and the foam solution are prepared into a test solution in a volume ratio of 1:500;

[0038] In step S3, the preset time for the film frame to stay in the test solution is 30 minutes.

[0039] Since the method for measuring the thickness of a foam film by a fluorescence method of the present invention is applied to the above-mentioned device for measuring the thickness of a foam film by a fluorescence method, it has the advantages of the above-mentioned device for measuring the thickness of a foam film by a fluorescence method, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 A schematic diagram of the structure of a device for measuring the thickness of a foam film using a fluorescence method provided by an embodiment of the present invention;

[0042] Figure 2 A schematic diagram of the structure of a device for measuring the thickness of a foam film by a fluorescence method provided by an embodiment of the present invention for a fluorescence calibration test;

[0043] Figure 3 A schematic diagram of the structure of a fluorescence calibration device provided in an embodiment of the present invention;

[0044] Figure 4 It is a schematic diagram of the high-speed camera of the present invention vertically photographing the foam film on the film frame.

[0045] in:

[0046] 1. Constant temperature and humidity cabinet, 2. Control panel, 3. Cabinet, 4. First sliding base, 5. First connecting rod, 6. Ball joint socket, 7. Ball joint, 8. Film frame, 9. Pulse laser transmitter, 10. Cabinet door, 11. Computer, 12. Second sliding base, 13. Second connecting rod, 14. Slide rail, 15. High-speed camera, 16. Lifting frame, 17. Support plate, 18. Foam solution container, 19. Water bath heating table, 20. Fluorescence calibration device. DETAILED DESCRIPTION

[0047] The invention discloses a device for measuring the thickness of a foam film by a fluorescence method, which can accurately measure the change of the thickness of the foam film over time, intuitively reflect the stability of the bubble film, avoid the interference of environmental factors on the measurement, have higher accuracy of the test result, stronger measurement repeatability, and a wide range of application.

[0048] The invention also discloses a method for measuring the thickness of the foam film by using a fluorescence method.

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] See also Figure 1 The device for measuring the thickness of foam film by fluorescence method of the present invention comprises a constant temperature and humidity cabinet 1, a water bath heating platform 19, a foam solution container 18, a pulse laser emitter 9, a film mechanism and a high-speed camera 15. The water bath heating platform 19 can be raised and lowered in the cabinet 3 of the constant temperature and humidity cabinet 1, and the cabinet door 10 is rotatably connected to the opening side of the cabinet 3. For the convenience of observation, the cabinet door 10 can be a transparent glass door. The water bath heating platform 19 comprises a heating component and a heating tank connected to the heating component, and the heating tank is used to hold the heated liquid. The water bath heating platform 19 is an existing device, and its details are not repeated here. The foam solution container 18 is used to hold the configured foam solution mixed with the fluorescent agent and is placed on the water bath heating platform 19. The pulse laser emitter 9 is installed in the cabinet 3 of the constant temperature and humidity cabinet 1. The pulse laser emitter 9 is used to emit monochromatic light of set wavelength and intensity. The wavelength emitted by the pulse laser emitter 9 is consistent with the fluorescence excitation wavelength of the foam solution. The film mechanism is slidably disposed in the cabinet body 3 of the constant temperature and humidity cabinet 1. The film mechanism includes a film frame 8. The film frame 8 is used to form a foam film. By slidably disposing the film mechanism, the film frame 8 is conveniently extended into the foam solution in the foam solution container 18. In order to facilitate adjustment of the shooting position, the high-speed camera 15 is slidably disposed in the cabinet body 3 of the constant temperature and humidity cabinet 1.

[0051] Among them, a computer 11 is arranged outside the constant temperature and humidity cabinet 1, and the computer 11 is connected to the high-speed camera 15 and the pulse laser transmitter 9. The high-speed camera 15 is connected to the computer 11 so that the real-time image captured by the high-speed camera 15 is displayed on the display screen of the computer 11.

[0052] The device for measuring the thickness of the foam film by the fluorescence method of the present invention can accurately measure the change of the thickness of the foam film over time by setting a film frame 8 for forming and supporting the foam film, a pulse laser emitter 9 for emitting monochromatic light of a set wavelength, and a high-speed camera 15 for shooting, so as to intuitively reflect the stability of the bubble film and better evaluate the liquid separation characteristics of the foam. The film frame 8, the pulse laser emitter 9, and the high-speed camera 15 are all arranged in a constant temperature and humidity cabinet 1. During the foam film observation process, the test space is relatively closed and the temperature and humidity are kept constant for a long time, which can maximize the avoidance of interference from environmental factors, and the accuracy of the test results is higher. The device for measuring the thickness of the foam film by the fluorescence method of the present invention can adjust the temperature of the foam liquid, and can explore the thickness and morphological changes of different types of foam liquids and liquid films at different temperatures by changing the type of foam liquid, which has application value in the field of fire foam research. The device for measuring the thickness of the foam film by the fluorescence method of the present invention has a simple structure, convenient operation, strong repeatability, can change the temperature and humidity of the environment as needed, and has a wide range of applications.

[0053] In order to facilitate the sliding support of the high-speed camera 15 and the film mechanism, a slide rail 14 is provided in the cabinet 3. The slide rail 14 is arranged around the longitudinal section of the cabinet 3. Figure 1 As shown, the slide rail 14 is arranged parallel to the cabinet door 10. The film mechanism and the high-speed camera 15 are slidably connected to the slide rail 14. When the film mechanism and the high-speed camera 15 slide to a suitable position on the slide rail 14, they can be tightened and limited by a limit screw. When the high-speed camera 15 moves to a suitable position, the high-speed camera 15 can vertically shoot the foam film on the film frame 8. The vertical shooting here means that the central axis of the lens of the high-speed camera 15 is arranged along the central line of the film frame 8, such as Figure 4 As shown, the lens of the high-speed camera 15 is arranged parallel to the film frame 8. In order to facilitate the high-speed camera 15 and the film mechanism to slide freely at the corners of the slide rail 14, the bending position of the slide rail 14 is a track arranged in an arc shape, and the slide rail 14 is arranged along the four sides of the cabinet 3 into a rounded rectangular track, such as Figure 1 shown.

[0054] Specifically, the film mechanism includes a first sliding base 4, a first connecting rod 5 and a film frame 8, wherein the first sliding base 4 is slidably connected to the slide rail 14, the first connecting rod 5 is connected to the first sliding base 4, and the film frame 8 is rotatably connected to the first connecting rod 5. One end of the first connecting rod 5 is rotatably connected to the film frame 8, and the other end is fixedly connected to the first sliding base 4. The first sliding base 4 slides on the slide rail 14, thereby driving the position change of the film frame 8. The film frame 8 is rotatably connected to the first connecting rod 5, so as to facilitate the adjustment of the angle of the film frame 8.

[0055] In order to increase the angle adjustment range of the film frame 8, the first connecting rod 5 is rotatably connected to the film frame 8 through a ball joint connection structure. Specifically, the ball joint connection structure includes a ball joint holder 6 and a ball joint 7, and the ball joint 7 is rotatably connected to the slot of the ball joint holder 6. In one embodiment, the ball joint holder 6 is fixedly connected to the end of the first connecting rod 5, and the end of the ball joint 7 away from the ball joint holder 6 is fixedly connected to the film frame 8. The direction and position of the film frame 8 are adjusted by rotating the ball joint 7 360° in the ball joint holder 6, so that the position of the film frame 8 can meet the shooting position requirements of the high-speed camera 15. In order to ensure the reliability of the position, the first sliding base 4 can be positioned by a limit screw.

[0056] In one embodiment, the high-speed camera 15 is slidably connected to the slide rail 14 via the second slide base 12, and the high-speed camera 15 and the second slide base 12 are connected via a second connecting rod 13, one end of the second connecting rod 13 is fixedly connected to the high-speed camera 15, and the other end is connected to the second slide base 12. The second slide base 12 slides on the slide rail 14, thereby changing the position of the high-speed camera 15. In order to ensure the reliability of the position of the high-speed camera 15, the second slide base 12 is positioned by a limit screw.

[0057] In order to facilitate the lifting and lowering of the water bath heating table 19, a lifting support frame is provided on the bottom plate of the cabinet body 3 of the constant temperature and humidity cabinet 1, and the lifting support frame includes a lifting frame 16 and a support plate 17 connected to the top of the lifting frame 16, and the lifting frame 16 is a retractable frame structure. The water bath heating table 19 is placed on the support plate 17. Specifically, the lifting frame 16 includes a plurality of cross rod groups hinged in sequence, each of the cross rod groups includes a first rod and a second rod hinged and crossed in the middle, and the intersection of the first rod and the second rod is hinged. The lifting frame 16 is driven to lift and lower by a linear drive device, and the bottom of the lifting frame 16 is fixedly connected to the bottom plate of the constant temperature and humidity cabinet 1. In one embodiment, the linear drive device is a cylinder, the cylinder body of the cylinder is connected to the bottom plate of the constant temperature and humidity cabinet 1, and the rod end of the cylinder is hinged to the bottom of the support plate 17 or on the rod of the lifting frame 16 close to the support plate 17.

[0058] In order to facilitate the adjustment of the temperature and humidity of the constant temperature and humidity cabinet 1, a control panel 2 is provided on the constant temperature and humidity cabinet 1, and the control panel 2 controls the temperature and humidity in the cabinet body 3 through corresponding operation buttons. The control panel 2 is also provided with buttons for controlling the heating temperature of the water bath heating platform 19, and the heating temperature of the water bath heating platform 19 is adjusted by operating the corresponding control buttons. At the same time, the control panel 2 is also provided with buttons for controlling the lifting and lowering of the lifting support frame, and the lifting and lowering of the lifting support frame is realized by operating the corresponding control buttons.

[0059] The device for measuring the thickness of a foam film by a fluorescence method of the present invention has a simple structure, can accurately measure and display the change of the thickness of the foam film over time, intuitively reflects the stability of the bubble film, has strong repeatability, can be applied to the measurement of the foam thickness under different temperatures and humidity, and has a wide range of applications.

[0060] The present invention also provides a method for measuring the thickness of a foam film by a fluorescence method, comprising the steps of:

[0061] S1. Evenly mix the fluorescent agent and the foam solution according to a set volume ratio, and pour the mixture into a foam solution container 18 . The foam solution container 18 is placed on a water bath heating table 19 in a constant temperature and humidity cabinet 1 .

[0062] In this step, the test solution is prepared by the volume ratio of the fluorescent agent and the foam solution at 1:500, and the solution is poured into the foam solution container 18. The height of the test solution is at least half of the height of the foam solution container 18, so that the film frame 8 of the film mechanism can be immersed in the solution.

[0063] S2. Adjust the position of the film mechanism so that the film frame 8 of the film mechanism is completely immersed in the test solution in the foam solution container 18.

[0064] Adjust the position of the first sliding base 4 on the slide rail 14, adjust the film frame 8 to the top of the foam solution container 18, adjust the height of the water bath heating platform 19, make the film frame 8 extend into the foam solution container 18 on the water bath heating platform 19, and make the film frame 8 completely immersed in the test solution. Control the temperature and humidity in the cabinet 3 through the control panel 2, and adjust the heating temperature of the water bath heating platform 19.

[0065] S3, after the film frame 8 stays in the test solution for a preset time, the position of the high-speed camera 15 is adjusted so that the lens of the high-speed camera 15 can vertically shoot the foam film generated on the film frame 8, and the pulse laser emitter 9 is turned on.

[0066] After the film frame 8 stays in the test solution for a preset time, the pulse laser emitter 9 and the high-speed camera 15 are turned on. In one embodiment, the preset time is 30 minutes, that is, the film frame 8 is pre-balanced in the solution for 30 minutes, so as to ensure that there is a certain atmosphere in the cabinet 3, and the gas above the foam solution reaches the saturated vapor pressure, thereby preventing errors in the measurement results of the liquid separation speed due to the large amount of evaporation of the film liquid during the test, and improving the accuracy of the measurement.

[0067] S4, adjusting the height of the water bath heating platform 19 so that the film frame 8 is away from the foam solution container 18, and a foam film is generated on the film frame 8 at this time.

[0068] In this step, the height of the support plate 17 is changed by the control panel 2. Specifically, the control panel 2 controls the support plate 17 to descend so that the film frame 8 leaves the liquid surface of the test solution, and a film is generated on the film frame 8. After the film is generated, due to the effect of gravity, the liquid in the film flows downward and discharges the film. This process is the liquid separation process of the foam film. This process will cause the film thickness to change, and then cause the fluorescence intensity to change over time. When changing the height of the high-speed camera 15, observe the screen of the computer 11 until the film frame 8 is completely within the field of view of the camera, that is, adjust the focal length of the high-speed camera 15 so that the field of view of the film being photographed in the camera is maximized as much as possible, so as to facilitate the observation of the dynamic changes of the film.

[0069] S5. Use the high-speed camera 15 to photograph the change of the fluorescence intensity of each location of the foam film on the film frame 8 over time.

[0070] The emission frequency f1 of the pulse laser emitter 9 and the shooting frequency f2 of the high-speed camera 15 are set on the computer 11 so that the two differ by half a cycle, ensuring that the picture screen when the high-speed camera 15 is shooting only has the image photo of fluorescence excitation. The software on the computer 11 is used to analyze the fluorescence intensity photo taken by the high-speed camera 15, and the film thickness corresponding to each fluorescence photo is obtained through the formula of fluorescence intensity and film thickness obtained by the fluorescence calibration test, and the change of film thickness distribution over time is analyzed as an indicator to measure the liquid separation speed of the foam film.

[0071] The steps of the fluorescence calibration test method include:

[0072] 1) Mix the fluorescent agent and foam solution evenly. The volume ratio of the fluorescent agent to the foam solution should refer to the fluorescent solution to be measured.

[0073] Specifically, the test solution is prepared by mixing the selected fluorescent agent and the foam solution in a volume ratio of 1:500. The selected fluorescent agent should have no effect on the properties of the foam solution, and the fluorescence excitation wavelength and the laser emission wavelength should be consistent.

[0074] 2) Pour the test solution into the spherical groove above the fluorescent calibration device 20, and place the fluorescent calibration device 20 on the water bath heating platform 19. Figure 2 shown.

[0075] The temperature and humidity in the cabinet 3 are set through the control panel 2, and the temperature of the water bath on the water bath heating table 19 is adjusted. The liquid level of the test solution in the spherical groove above the fluorescent calibration device 20 is level with the notch of the groove. The fluorescent calibration device 20 is placed in the water bath heating table 19 and left to stand for 15 minutes to ensure that the gas-liquid temperature remains consistent.

[0076] 3) Adjust the pulse laser emitter 9 and the high-speed camera 15 along the slide rail 14 to just above the fluorescent calibration device 20, adjust the height of the support plate 17, and observe the screen of the computer 11 until the entire circular liquid surface is within the field of view of the camera.

[0077] The emission frequency f1 of the pulse laser emitter 9 and the shooting frequency f2 of the high-speed camera 15 are set on the computer 11 to differ by half a cycle, so as to ensure that the pictures taken by the high-speed camera 15 only include the pictures excited by fluorescence.

[0078] 4) Use the high-speed camera 15 to take multiple fluorescence photos of the test solution in the fluorescence calibration device 20.

[0079] Use the fluorescence calibration device 20 for calibration: Among them, I f is the fluorescence intensity per unit area, I e is the excitation light intensity, ε is the absorption coefficient of the fluorescent substance, C is the concentration of the fluorescent substance, is the fluorescence quantum yield, t is the liquid film thickness, and the liquid film thickness (see Figure 3 )for: Where r is the radius of the spherical groove on the fluorescence calibration device 20, and x is the distance from the measuring point to the center of the sphere. When the excitation light intensity and the concentration of the fluorescent substance are constant, the fluorescence intensity and the liquid film thickness are proportional. After calibration by the fluorescence calibration device 20, we can obtain the relationship between the fluorescence intensity and the liquid film thickness, which can be used as an indicator to measure the corresponding relationship between the sample foam liquid film thickness and the fluorescence intensity. Figure 3 The parameter d in has no effect on the liquid film thickness.

[0080] Example 1

[0081] Mix the fluorescent agent and 3% aqueous film-forming foam solution evenly and pour them into the foam solution container 18. First, prepare the test solution with the fluorescent agent and 3% aqueous film-forming foam solution in a volume ratio of 1:500, and pour the solution into the foam solution container 18, so that the test solution fills half of the volume of the foam solution container 18. The film frame 8 is completely immersed in the test solution. The temperature and humidity in the cabinet 3 and the temperature of the water bath heating table 19 are controlled by the control panel 2. After the film frame 8 stays in the test solution for a preset time, the pulse laser emitter 9 and the high-speed camera 15 are turned on, so that the high-speed camera 15 vertically shoots the film on the film frame 8. The film frame 8 stays in the test solution for 30 minutes. The film frame 8 is pre-balanced in the solution for 30 minutes to ensure that there is a certain atmosphere in the cabinet 3 and the gas above the foam solution reaches the saturated vapor pressure. Prevent errors in the measurement results of the liquid separation rate due to the large amount of evaporation of the film liquid during the experiment. Adjust the height of the water bath heating table 19 so that the film frame 8 leaves the liquid surface of the test solution, and a foam film is generated on the film frame 8. After the foam film is produced, due to the effect of gravity, the liquid in the film flows downward and discharges from the film. This process is the liquid separation process of the foam film. This process will cause the film thickness to change, which in turn causes the fluorescence intensity to change over time. Use a high-speed camera 15 to record the change in fluorescence intensity over time at various locations of the foam film. On the computer 11, set the emission frequency f1 of the pulse laser transmitter 9 and the shooting frequency f2 of the high-speed camera 15 to differ by half a cycle to ensure that the camera only takes photos of fluorescence excitation. Use the software on the computer 11 to analyze the fluorescence intensity photos taken, and obtain the film thickness corresponding to each fluorescence photo through the fluorescence intensity-film thickness formula obtained by the fluorescence calibration test. Analyze the change in film thickness distribution over time as an indicator to measure the liquid separation speed of the foam film.

[0082] In the description of this solution, it should be understood that the terms "upper", "lower", "vertical", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this solution.

[0083] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this solution, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0084] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0085] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A device for measuring the thickness of foam film by fluorescence method, It is characterized in that include: Constant temperature and humidity cabinet; A water bath heating table, which can be raised and lowered and arranged inside the constant temperature and humidity cabinet; A foam solution container, used for containing the foam solution, is placed on the water bath heating table; A pulse laser transmitter is installed in the constant temperature and humidity cabinet, and is used to emit monochromatic light of set wavelength and intensity; A film mechanism is slidably disposed in the cabinet body of the constant temperature and humidity cabinet, and the film mechanism comprises a film frame, and the film frame is used to form a foam film; The high-speed camera is slidably arranged in the cabinet of the constant temperature and humidity cabinet.

2. The device for measuring the thickness of foam film by fluorescence method according to claim 1, It is characterized in that A slide rail is provided in the cabinet, and the slide rail is arranged around the longitudinal section of the cabinet. The film mechanism and the high-speed camera are slidably connected to the slide rail, so that the high-speed camera can vertically shoot the foam film on the film frame; The bending position of the slide rail is a track arranged in an arc shape.

3. The device for measuring the thickness of foam film by fluorescence method according to claim 2, It is characterized in that The film mechanism comprises: A first sliding base, slidably connected to the slide rail; A first connecting rod connected to the first sliding base; A film frame, rotatably connected to the first connecting rod; One end of the first connecting rod is rotatably connected to the film frame, and the other end is fixedly connected to the first sliding base.

4. The device for measuring the thickness of foam film by fluorescence method according to claim 3, It is characterized in that The first connecting rod is rotatably connected to the film frame via a ball joint connection structure; The ball joint connection structure comprises a ball joint holder and a ball joint, and the ball joint is rotatably connected in a slot of the ball joint holder; The ball joint holder is fixedly connected to the first connecting rod, and one end of the ball joint away from the ball joint holder is fixedly connected to the film frame.

5. The device for measuring the thickness of foam film by fluorescence method according to claim 2, It is characterized in that The high-speed camera is slidably connected to the slide rail via a second sliding base; The high-speed camera is connected to the second sliding base via a second connecting rod, one end of the second connecting rod is fixedly connected to the high-speed camera, and the other end of the second connecting rod is connected to the second sliding base.

6. The device for measuring the thickness of foam film by fluorescence method according to claim 1, It is characterized in that A lifting support frame is provided on the bottom plate of the constant temperature and humidity cabinet, and the lifting support frame includes a lifting frame and a support plate connected to the top of the lifting frame. The lifting frame is a retractable frame structure, and the lifting frame is driven to rise and fall by a linear drive device. The bottom of the lifting frame is fixedly connected to the bottom plate of the constant temperature and humidity cabinet; The water bath heating platform is placed on the supporting plate.

7. The device for measuring the thickness of foam film by fluorescence method according to claim 6, It is characterized in that The constant temperature and humidity cabinet is provided with a control panel, and the control panel is used to control the temperature and humidity of the internal environment of the cabinet body of the constant temperature and humidity cabinet, the heating temperature of the water bath heating table and the lifting and lowering of the lifting support frame.

8. A method for measuring the thickness of foam film by fluorescence method, It is characterized in that Includes steps: S1. Mix the fluorescent agent and the foam solution evenly according to a set volume ratio, and pour the mixture into a foam solution container, which is placed on a water bath heating table in a constant temperature and humidity cabinet; S2, adjusting the position of the film mechanism so that the film frame of the film mechanism is completely immersed in the test solution in the foam solution container; S3, after the film frame stays in the test solution for a preset time, adjust the position of the high-speed camera so that the lens of the high-speed camera can vertically shoot the foam film on the film frame, and turn on the pulse laser emitter; S4, adjusting the height of the water bath heating platform so that the film frame is away from the foam solution container, and a foam film is generated on the film frame; S5. Recording the change of the fluorescence intensity of each location of the foam film on the film frame over time by the high-speed camera.

9. The method for measuring the thickness of foam film by fluorescence method according to claim 8, It is characterized in that The step S5 also includes a step S6, using software to analyze the fluorescence intensity photos taken by the high-speed camera, obtaining the film thickness corresponding to each fluorescence photo through the fluorescence intensity and film thickness formula obtained by the fluorescence calibration test, and analyzing the change of film thickness distribution over time as an indicator to measure the liquid separation speed of the foam film.

10. The method for measuring the thickness of foam film by fluorescence method according to claim 8, It is characterized in that In the step S1, the fluorescent agent and the foam solution are prepared into a test solution according to a volume ratio of 1:500; In the step S3, the preset time for the film frame to stay in the test solution is 30 minutes.

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