Device and method for measuring foam film thickness using fluorescence method

Abstract

The present invention discloses a device for measuring the thickness of a foam film using a fluorescence method, comprising a constant temperature and humidity cabinet, a water bath heating platform, a foam solution container, a pulsed laser emitter, a film mechanism, and a high-speed camera. The water bath heating platform can be raised and lowered within the constant temperature and humidity cabinet; the foam solution container is used to hold the foam solution and is placed on the water bath heating platform; the pulsed laser emitter is installed within the constant temperature and humidity cabinet, and is used to emit monochromatic light of a set wavelength and intensity; the film mechanism is slidably disposed within the constant temperature and humidity cabinet, and the film mechanism includes a film frame, which is used to form a foam film; and the high-speed camera is slidably disposed within the constant temperature and humidity cabinet. The device for measuring the thickness of a foam film using a fluorescence method of the present invention can accurately measure changes in the thickness of the foam film over time, has higher test results accuracy, stronger measurement repeatability, and a wide range of applications. The present invention also provides a method for measuring the thickness of a foam film using a 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 using a fluorescence method. Background Art

[0002] With the rapid development of the economy and technology, fires have become frequent, causing enormous losses. Liquid fires, due to their rapid spread, intense combustion, and susceptibility to explosion, are difficult to effectively control once they occur, often resulting in severe casualties and property damage. Foam fire extinguishing agents, thanks to their dual cooling and suppression properties, offer excellent fire extinguishing effectiveness and anti-reignition properties, making them widely used in liquid fires. Foam stability, a key factor influencing foam performance, directly determines the effectiveness and anti-reignition properties of foam fire extinguishing agents.

[0003] The generally accepted theory at this stage is that foam stability is primarily affected by three factors: bubble coarsening, coalescence, and liquid precipitation. The liquid precipitation time at 25% and 50% foam mass is used as a standard and important means of measuring foam stability. However, the calculation of foam liquid precipitation time using this method is significantly affected by the external environment and human manipulation, and the test results are subject to certain deviations and randomness. Furthermore, this method can only reflect foam stability through the mass and speed of liquid precipitation from the foam, and cannot directly reflect the stability of bubbles and thin films. Therefore, the test results are low in precision and poor in repeatability, which has certain application limitations for experimental research on foam properties. Summary of the Invention

[0004] In view of this, the present invention provides a device for measuring the thickness of a foam film using a fluorescence method, which can accurately measure the change in 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 has higher test results accuracy, stronger measurement repeatability, and a wide range of applications.

[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 using a fluorescence method, comprising:

[0008] Constant temperature and humidity cabinet;

[0009] A water bath heating platform is arranged in a liftable manner 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 emitter 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 includes 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 body 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 includes:

[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 includes a ball joint holder and a ball joint, and the ball joint is rotatably connected to the 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 is connected to the second sliding base.

[0026] Optionally, a lifting support frame is provided on the bottom plate of the constant temperature and humidity cabinet, 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, 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, which 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 platform, and the lifting and lowering of the lifting support frame.

[0029] It can be seen from the above technical solutions that the device for measuring the thickness of a foam film by a fluorescence method provided by the present invention, by providing 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, can accurately measure the change in the thickness of the foam film over time, intuitively reflect the stability of the bubble film, and better evaluate the liquid separation characteristics of the foam. The film frame, pulsed laser emitter, and high-speed camera are all set in a constant temperature and humidity cabinet. 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 increase the accuracy of the test results. The device for measuring the thickness of a foam film by a 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, and has application value in the field of firefighting foam research. The device for measuring the thickness of a foam film by a fluorescence method of the present invention has a simple structure, is easy to operate, has 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 using a fluorescence method, comprising the steps of:

[0031] S1. Mix the fluorescent agent and foam solution in a set volume ratio and pour the mixture into a foam solution container. Place the foam solution container on a water bath heating platform in a constant temperature and humidity cabinet.

[0032] S2. Adjust 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 capture 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 formed on the film frame;

[0035] S5. Recording the change of fluorescence intensity at various locations of the foam film on the film frame over time using the high-speed camera.

[0036] Optionally, step S5 is followed by step S6, wherein software is used to analyze the fluorescence intensity photographs taken by the high-speed camera, and the film thickness corresponding to each fluorescence photograph is obtained by using the fluorescence intensity and film thickness formula obtained through the fluorescence calibration test. The change in film thickness distribution over time is analyzed as an indicator for measuring 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 at 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 of measuring foam film thickness by fluorescence method of the present invention is applied to the above-mentioned device for measuring foam film thickness by fluorescence method, it has the advantages of the above-mentioned device for measuring foam film thickness by 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 following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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 any creative work.

[0041] Figure 1 A schematic structural diagram of a device for measuring the thickness of a foam film using a fluorescence method according to 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 using a fluorescence method provided by an embodiment of the present invention for use in a fluorescence calibration test;

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

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

[0045] in:

[0046] 1. Constant temperature and humidity cabinet, 2. Control panel, 3. Cabinet body, 4. First sliding base, 5. First connecting rod, 6. Ball joint holder, 7. Ball joint, 8. Film frame, 9. Pulse laser emitter, 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 present invention discloses a device for measuring the thickness of a foam film using a fluorescence method. The device 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 has higher accuracy of the test results, stronger measurement repeatability, and a wide range of applications.

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

[0049] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0050] See Figure 1 The device for measuring the thickness of a foam film by a 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 pulsed 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 body 3 of the constant temperature and humidity cabinet 1, and the cabinet door 10 is rotatably connected to the open side of the cabinet body 3. In order to facilitate observation, the cabinet door 10 can be a transparent glass door. The water bath heating platform 19 includes a heating component and a heating tank connected to the heating component. The heating tank is used to hold a 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 a prepared foam solution mixed with a fluorescent agent and is placed on the water bath heating platform 19. The pulsed laser emitter 9 is installed in the cabinet body 3 of the constant temperature and humidity cabinet 1. The pulsed laser emitter 9 is used to emit monochromatic light of set wavelength and intensity. The wavelength emitted by the pulsed laser emitter 9 is consistent with the fluorescence excitation wavelength of the foam solution. The film mechanism is slidably mounted within the cabinet 3 of the constant temperature and humidity cabinet 1. The film mechanism includes a film frame 8, which is used to form the foam film. The slidable mounting of the film mechanism facilitates the insertion of the film frame 8 into the foam solution in the foam solution container 18. To facilitate adjustment of the filming position, a high-speed camera 15 is slidably mounted within the cabinet 3 of the constant temperature and humidity cabinet 1.

[0051] Among them, the constant temperature and humidity cabinet 1 is provided with a computer 11, which 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 a foam film using a fluorescence method of the present invention is capable of accurately measuring the change in the thickness of the foam film over time by providing a film frame 8 for forming and supporting the foam film, a pulsed laser emitter 9 for emitting monochromatic light of a set wavelength, and a high-speed camera 15 for shooting. This can intuitively reflect the stability of the bubble film and better evaluate the liquid separation characteristics of the foam. The film frame 8, the pulsed 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 increase the accuracy of the test results. The device for measuring the thickness of a foam film using a fluorescence method of the present invention can adjust the temperature of the foam liquid. By changing the type of foam liquid, the thickness and morphological changes of the liquid film under different types of foam liquids and at different temperatures can be explored. It has application value in the field of firefighting foam research. The device for measuring the thickness of a foam film using a fluorescence method of the present invention has a simple structure, is easy to operate, has 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 the appropriate position of the slide rail 14, they can be tightened and limited by the limit screw. When the high-speed camera 15 moves to the appropriate 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 set along the center line of the film frame 8, as shown in FIG. 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 bend position of the slide rail 14 is a circular arc-shaped track, and the slide rail 14 is arranged along the four sides of the cabinet 3 into a rounded rectangular track, as shown in FIG. Figure 1 shown.

[0054] Specifically, the film mechanism includes a first sliding base 4, a first connecting rod 5, and a film frame 8. The first sliding base 4 is slidably connected to a slide rail 14, the first connecting rod 5 is connected to the first sliding base 4, and the film frame 8 is rotationally connected to the first connecting rod 5. One end of the first connecting rod 5 is rotationally 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 of the film frame 8. The film frame 8 is rotationally connected to the first connecting rod 5, facilitating 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, a high-speed camera 15 is slidably connected to a slide rail 14 via a second slide base 12. 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. To ensure the reliable position of the high-speed camera 15, the second slide base 12 is positioned using a set screw.

[0057] In order to facilitate the lifting and lowering of the water bath heating platform 19, a lifting support frame is provided on the bottom plate of the cabinet body 3 of the constant temperature and humidity cabinet 1. The lifting support frame includes a lifting frame 16 and a support plate 17 connected to the top of the lifting frame 16. The lifting frame 16 is a retractable frame structure. The water bath heating platform 19 is placed on the support plate 17. Specifically, the lifting frame 16 includes a plurality of cross rod groups hinged in sequence. Each cross rod group includes a first rod and a second rod hinged in the middle, and the intersection of the first rod and the second rod is hinged. The lifting frame 16 is driven to rise and fall by a linear drive device. 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 to the rod of the lifting frame 16 near the support plate 17.

[0058] To facilitate adjustment of the temperature and humidity within the constant temperature and humidity cabinet 1, a control panel 2 is provided. Control panel 2 controls the temperature and humidity within the cabinet 3 via corresponding operating buttons. Control panel 2 also includes buttons for controlling the heating temperature of the water bath heating platform 19. Operating these buttons adjusts the heating temperature of the water bath heating platform 19. Control panel 2 also includes buttons for controlling the elevation of the lifting support frame. Operating these buttons raises or lowers the lifting support frame.

[0059] The device for measuring the thickness of a foam film using a fluorescence method of the present invention has a simple structure, can accurately measure and display the change of the foam film thickness over time, intuitively reflects the stability of the bubble film, has strong repeatability, can be applied to measure 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 using 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 the foam solution container 18 . The foam solution container 18 is placed on the water bath heating platform 19 in the constant temperature and humidity cabinet 1 .

[0062] In this step, the test solution is prepared by mixing the fluorescent agent and the foam solution in a volume ratio of 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 first sliding base 4 on slide rail 14, position film frame 8 above foam solution container 18, and adjust the height of water bath heating platform 19 so that film frame 8 extends into foam solution container 18 on water bath heating platform 19 and is completely immersed in the test solution. Control the temperature and humidity inside cabinet 3 and adjust the heating temperature of water bath heating platform 19 using control panel 2.

[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 capture the foam film generated on the film frame 8, and the pulse laser emitter 9 is turned on.

[0066] After the film frame 8 has been in the test solution for a preset time, the pulsed laser emitter 9 and high-speed camera 15 are turned on. In one embodiment, the preset time is 30 minutes, meaning that the film frame 8 is pre-equilibrated in the solution for 30 minutes. This ensures a constant atmosphere within the cabinet 3 and that the gas above the foam solution reaches saturated vapor pressure. This prevents errors in the evaporation velocity measurement due to substantial evaporation of the film liquid during the test, thereby improving measurement accuracy.

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

[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 thin film is formed on the film frame 8. After the film is formed, 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 causes the film thickness to change, and then causes the fluorescence intensity to change over time. When changing the height of the high-speed camera 15, the screen of the computer 11 is observed until the film frame 8 is entirely within the camera's field of view, that is, the focal length of the high-speed camera 15 is adjusted to maximize the field of view of the film being photographed in the camera, making it easier to observe the dynamic changes of the film.

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

[0070] On computer 11, the emission frequency f1 of pulsed laser emitter 9 and the shooting frequency f2 of high-speed camera 15 are set to differ by half a cycle, ensuring that the images captured by high-speed camera 15 only contain images of fluorescence excitation. Software on computer 11 is used to analyze the fluorescence intensity images captured by high-speed camera 15. The film thickness corresponding to each fluorescence image is calculated using the formula for fluorescence intensity and film thickness obtained from fluorescence calibration experiments. The film thickness distribution over time is analyzed as an indicator of the liquid separation rate 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 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 fluorescence calibration device 20, and place the fluorescence calibration device 20 on the water bath heating platform 19. Figure 2 shown.

[0075] Set the temperature and humidity in the cabinet 3 through the control panel 2, adjust the temperature of the water bath on the water bath heating table 19, and make sure that 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. Place the fluorescent calibration device 20 in the water bath heating table 19 and let it stand for 15 minutes to ensure that the gas and liquid temperatures remain 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 camera's field of view.

[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 high-speed camera 15 only captures fluorescence-excited photos.

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

[0079] Calibrate using the fluorescence calibration device 20: 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 thickness of the liquid film, and the thickness of the liquid film (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 measurement point to the center of the sphere. When the excitation light intensity and fluorescent substance concentration are constant, the fluorescence intensity and liquid film thickness are directly proportional. After calibration using the fluorescence calibration device 20, we can derive a relationship between fluorescence intensity and liquid film thickness, which serves as an indicator for measuring the correspondence between sample foam liquid film thickness and 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 the mixture into the foam solution container 18. First, prepare the test solution by mixing the fluorescent agent and 3% aqueous film-forming foam solution in a volume ratio of 1:500. Pour the solution into the foam solution container 18, filling half of the container 18 with the test solution. Completely immerse the film frame 8 in the test solution. Control the temperature and humidity within the cabinet 3 and the temperature of the water bath heating platform 19 using the control panel 2. After the film frame 8 has been in the test solution for a preset time, turn on the pulsed laser emitter 9 and high-speed camera 15, allowing the camera 15 to vertically capture the film on the film frame 8. Allow the film frame 8 to remain in the test solution for 30 minutes. Allow the film frame 8 to pre-equilibrate in the solution for 30 minutes to ensure a consistent atmosphere within the cabinet 3 and that the gas above the foam solution reaches saturated vapor pressure. This prevents errors in the evaporation velocity measurement due to significant evaporation of the film liquid during the experiment. Adjust the height of the water bath heating platform 19 so that the film frame 8 is clear of the test solution surface, allowing a foam film to form 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 on the foam film. On the computer 11, set the emission frequency f1 of the pulsed laser emitter 9 and the shooting frequency f2 of the high-speed camera 15 to differ by half a cycle to ensure that the camera only captures fluorescence-excited photos when taking photos. Use the software on the computer 11 to analyze the taken fluorescence intensity photos, and obtain the fluorescence intensity-film thickness formula obtained through the fluorescence calibration test to obtain the film thickness corresponding to each fluorescence photo. 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. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as a limitation on this solution.

[0083] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of this solution, "plurality" means two or more, unless otherwise 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 is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily 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 is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A device for measuring the thickness of a foam film by fluorescence method, characterized in that: include: Constant temperature and humidity cabinet; A water bath heating platform is arranged in a liftable manner 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 emitter 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 includes a film frame, and the film frame is used to form a foam film; The high-speed camera is slidably arranged in the cabinet body of the constant temperature and humidity cabinet.

2. The device for measuring the thickness of foam film by fluorescence method according to claim 1, 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, 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, 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 includes a ball joint holder and a ball joint, and the ball joint is rotatably connected to the 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, 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 is connected to the second sliding base.

6. The device for measuring the thickness of foam film by fluorescence method according to claim 1, 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, characterized in that: The constant temperature and humidity cabinet is provided with a control panel, which 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 platform and the lifting and lowering of the lifting support frame.

8. A method for measuring the thickness of a foam film by fluorescence, characterized in that: The device for measuring the thickness of a foam film using the fluorescence method according to any one of claims 1 to 7 comprises the following steps: S1. Mix the fluorescent agent and foam solution in a set volume ratio and pour the mixture into a foam solution container. Place the foam solution container on a water bath heating platform in a constant temperature and humidity cabinet. S2. Adjust 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 capture 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 formed on the film frame; S5. Recording the change of fluorescence intensity at various locations of the foam film on the film frame over time using the high-speed camera.

9. The method for measuring the thickness of a foam film by fluorescence method according to claim 8, wherein: 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 the film thickness distribution over time as an indicator for measuring the liquid separation speed of the foam film.

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

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