An ultra-hydrophobic microstructure gas-liquid interface tracking observation device and an observation method thereof

Abstract

The application provides a super-hydrophobic microstructure gas-liquid interface tracking observation device and an observation method thereof, and belongs to the technical field of super-hydrophobic microstructure gas-liquid interface simulation test equipment. In the super-hydrophobic microstructure gas-liquid interface tracking observation device, an experimental water tank is fixed on a placing rack and arranged horizontally, a super-hydrophobic sample is placed in the experimental water tank, the experimental water tank can provide required working conditions for experiments, a constant-pressure water supply system is connected with the experimental water tank to form a closed environment, the constant-pressure water supply system can supply experimental water to the experimental water tank, an observation system is arranged on the side of the placing rack and can observe the position, shape and evolution process of a gas-liquid interface on the surface of the super-hydrophobic sample in the experimental water tank. The super-hydrophobic microstructure gas-liquid interface tracking observation device can observe the position, shape and evolution process of the gas-liquid interface on the surface of the super-hydrophobic sample, thereby helping to explore the evolution law of the gas-liquid interface and clear the damage mechanism of the gas layer.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of super-hydrophobic micro-structure gas-liquid interface simulation test equipment, and particularly relates to a super-hydrophobic micro-structure gas-liquid interface tracking observation device and an observation method thereof. BACKGROUND

[0002] The super-hydrophobic micro-structure drag reduction technology reduces the solid surface energy through super-hydrophobic means, so that the liquid slips on the super-hydrophobic surface, and reduces the wall surface viscous shear stress by using the physical property difference between the gas and the liquid, while the gas-liquid interface can be regarded as a free shear surface and has good slip characteristics.

[0003] However, in actual application, the super-hydrophobic surface is difficult to maintain for a long time under the action of high hydrostatic pressure, high-speed flow shear and gas diffusion, the gas-liquid interface deforms and loses stability under complex flow shear, resulting in collapse of the gas-liquid interface, so that the micro-structure cavity is infiltrated, thereby reducing the drag reduction effect or even increasing the drag. Therefore, the maintenance of the gas layer is the key to reducing the wall surface drag. In order to maintain the existence of the gas-liquid interface to ensure the drag reduction effect, it is necessary to explore the evolution law of the gas-liquid interface to clarify the damage mechanism of the gas layer. However, there is no device and method for observing the gas-liquid interface at present. SUMMARY

[0004] Therefore, in order to solve the problem that there is no device and method for observing the gas-liquid interface at present, the application provides a super-hydrophobic micro-structure gas-liquid interface tracking observation device and an observation method thereof.

[0005] To achieve the above purpose, the application adopts the following technical scheme:

[0006] A super-hydrophobic micro-structure gas-liquid interface tracking observation device comprises:

[0007] A placing rack;

[0008] An experimental water tank is fixedly arranged on the placing rack, and is arranged horizontally. A super-hydrophobic sample is placed in the experimental water tank, and the experimental water tank can provide the required working conditions for experiments.

[0009] A constant-pressure water supply system is connected with the experimental water tank to form a closed environment, and the constant-pressure water supply system can provide experimental water for the experimental water tank.

[0010] An observation system is arranged on the side of the placing rack, and can observe the position, shape and evolution process of the gas-liquid interface on the surface of the super-hydrophobic sample in the experimental water tank.

[0011] As a preferred scheme of the above-mentioned super-hydrophobic microstructure gas-liquid interface tracking observation device, the experimental water tank comprises an upper plate, a bottom plate, a boss cover and a water prism, the upper plate is fixedly connected with the bottom plate, a channel is arranged between the upper plate and the bottom plate, the channel comprises a front end diffusion section, a straight channel section and a rear end contraction section which are sequentially communicated, the bottom plate is provided with a square opening, the square opening is communicated with the straight channel section, the boss cover can close the square opening and fix the super-hydrophobic sample sheet, the water prism is fixedly arranged on the upper plate and located at a position corresponding to the placement position of the super-hydrophobic sample sheet, and is used for changing the light path to achieve total internal reflection on the surface of the super-hydrophobic sample sheet.

[0012] As a preferred scheme of the above-mentioned super-hydrophobic microstructure gas-liquid interface tracking observation device, a first sealing ring is arranged between the upper plate and the bottom plate, and the first sealing ring is used for sealing the channel.

[0013] As a preferred scheme of the above-mentioned super-hydrophobic microstructure gas-liquid interface tracking observation device, a second sealing ring is arranged between the boss cover and the bottom plate, and the second sealing ring is used for sealing the square opening.

[0014] As a preferred scheme of the above-mentioned super-hydrophobic microstructure gas-liquid interface tracking observation device, the distance between the start point of the straight channel section and the front end of the square opening should satisfy the formula:

[0015] L>0.057D h R e

[0016] Wherein, L is the distance between the start point of the straight channel section and the front end of the square opening; D h is the hydraulic diameter of the straight channel section; R e is the Reynolds number in the straight channel section, R e ≤2000;

[0017] The hydraulic diameter of the straight channel section is calculated according to the formula:

[0018]

[0019] Wherein: W is the width of the straight channel section; H c is the height of the straight channel section;

[0020] The distance between the rear end of the square opening and the tail of the straight channel section should be greater than or equal to 80 times the hydraulic diameter of the straight channel section.

[0021] As a preferred scheme of the super-hydrophobic microstructure gas-liquid interface tracking observation device, the constant-pressure water supply system comprises a constant-pressure water tank, a micro water pump, a water injection pipeline and a backflow pipeline, the input end of the micro water pump is communicated with the constant-pressure water tank, the output end of the micro water pump is communicated with the front-end diffusion section through the water injection pipeline, and the two ends of the backflow pipeline are respectively communicated with the rear-end contraction section and the constant-pressure water tank.

[0022] As a preferred scheme of the super-hydrophobic microstructure gas-liquid interface tracking observation device, the constant-pressure water supply system further comprises a micro flow meter, and the micro flow meter is arranged in the water injection pipeline and used for monitoring and regulating the flow in the experimental water tank.

[0023] As a preferred scheme of the super-hydrophobic microstructure gas-liquid interface tracking observation device, the constant-pressure water supply system further comprises a constant-pressure gas tank, the constant-pressure water tank is connected with the constant-pressure gas tank, and the constant-pressure gas tank can maintain the pressure of the closed environment.

[0024] As a preferred scheme of the super-hydrophobic microstructure gas-liquid interface tracking observation device, the observation system comprises an industrial microscope, a parallel light source, a movable support and a computer, the industrial microscope and the parallel light source are both mounted on the movable support, the industrial microscope and the parallel light source can move in the horizontal direction or the vertical direction on the movable support, the industrial microscope and the parallel light source are both provided with a polarizer, the movable support is arranged on the placing rack, the industrial microscope is connected with the computer, and the computer is used for displaying the position and shape information of the gas-liquid interface on the surface of the super-hydrophobic sample piece and displaying the evolution process of the gas-liquid interface.

[0025] The application further provides a super-hydrophobic microstructure gas-liquid interface tracking observation method, which adopts the super-hydrophobic microstructure gas-liquid interface tracking observation device, wherein the experimental water tank comprises an upper plate, a bottom plate, a boss cover and a water prism, the bottom plate is provided with a square opening; the observation system comprises an industrial microscope, a parallel light source, a movable support and a computer.

[0026] The super-hydrophobic microstructure gas-liquid interface tracking observation method comprises the following steps.

[0027] S1: placing the super-hydrophobic sample piece on the boss cover, and extending the boss cover into the channel from the square opening, so that the super-hydrophobic sample piece is clamped between the upper plate and the boss cover;

[0028] S2: connecting the constant-pressure water supply system with the experimental water tank, and injecting water into the constant-pressure water supply system;

[0029] S3: the constant pressure water supply system slowly supplies water to the experimental tank to eliminate air bubbles in the experimental tank;

[0030] S4: adjust the position of the industrial microscope and the parallel light source, so that the light path reaches the air-liquid interface on the surface of the super-hydrophobic sample piece after passing through the water prism and can form total internal reflection, and adjust the polarizer to adjust the light to the required polarization state;

[0031] S5: adjust the flow rate of water in the experimental tank to a set flow rate;

[0032] S6: take and record the position, shape and evolution process of the air-liquid interface on the surface of the super-hydrophobic sample piece.

[0033] Compared with the prior art, the super-hydrophobic microstructure air-liquid interface tracking observation device and the observation method thereof have the following beneficial effects:

[0034] 1. The super-hydrophobic microstructure air-liquid interface tracking observation device, the placing rack is used to install an experimental tank and an observation system, the experimental tank is fixedly arranged on the placing rack, and it is ensured that the experimental tank is in a horizontal state. A constant pressure water supply system is connected with the experimental tank to form a closed environment, the constant pressure water supply system can supply experimental water to the experimental tank, a super-hydrophobic sample piece is located in the experimental tank, the experimental tank provides a required working condition for experiments, and the observation system is arranged on the side of the placing rack. The observation system can observe the position, shape and evolution process of the air-liquid interface on the surface of the super-hydrophobic sample piece in the experimental tank. The super-hydrophobic microstructure air-liquid interface tracking observation device can observe the position, shape and evolution process of the air-liquid interface on the surface of the super-hydrophobic sample piece, thereby helping to explore the evolution law of the air-liquid interface to clarify the destruction mechanism of the air layer.

[0035] 2. The super-hydrophobic microstructure air-liquid interface tracking observation device, the position of the square opening is limited, and since the position of the super-hydrophobic sample piece is approximately at the position of the square opening, the position of the super-hydrophobic sample piece can be limited by limiting the position of the square opening. The distance L between the starting point of the straight slot section and the front end of the square opening satisfies the formula: L>0.057D h R e , which can ensure the complete development of laminar flow. The distance between the rear end of the square opening and the tail of the straight slot section is greater than or equal to 80 times the hydraulic diameter D h of the straight slot section, which can eliminate the influence of the wake flow on the flow in the front test area. BRIEF DESCRIPTION OF DRAWINGS

[0036] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application, illustrate embodiments of the application and assist in

[0037] In the drawings:

[0038] Figure 1 is a structural schematic diagram of a super-hydrophobic microstructure gas-liquid interface tracking observation device provided by specific embodiments of the application;

[0039] Figure 2 is an exploded view of an experimental water tank of the super-hydrophobic microstructure gas-liquid interface tracking observation device provided by specific embodiments of the application;

[0040] Figure 3 is a structural schematic diagram of an upper plate of the experimental water tank of the super-hydrophobic microstructure gas-liquid interface tracking observation device provided by specific embodiments of the application;

[0041] Figure 4 is a structural schematic diagram of a bottom plate of the experimental water tank of the super-hydrophobic microstructure gas-liquid interface tracking observation device provided by specific embodiments of the application;

[0042] Figure 5 is a structural schematic diagram of an observation system of the super-hydrophobic microstructure gas-liquid interface tracking observation device provided by specific embodiments of the application.

[0043] In the drawings:

[0044] 1, a rack;

[0045] 2, an experimental water tank; 21, an upper plate; 22, a bottom plate; 23, a water prism; 24, a boss gland; 211, a front end diffusion section; 212, a straight slot section; 213, a rear end contraction section; 221, a square opening; 222, a front end water inlet; 223, a rear end water outlet;

[0046] 3, a constant pressure water supply system; 31, a constant pressure water tank; 32, a micro water pump; 33, a water filling pipeline; 34, a backflow pipeline; 35, a micro flowmeter; 36, a constant pressure gas tank; 37, a pressure sensor;

[0047] 4, an observation system; 41, an industrial microscope; 42, a parallel light source; 43, a computer; 44, a movable support; 441, a first vertical guide rail; 442, a second vertical guide rail; 443, a horizontal guide rail; 444, a first vertical sliding block; 445, a second vertical sliding block; 446, a first horizontal sliding block; 447, a second horizontal sliding block. DETAILED DESCRIPTION

[0048] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It should be explained that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict, and the described embodiments are only some of the embodiments of the present application, not all the embodiments.

[0049] In the description of the present application, unless explicitly defined and limited, the terms "connected", "connected", "fixed" should be understood broadly, for example, can be fixedly connected, or can be detachably connected, or integrated; can be mechanically connected, or electrically connected; can be directly connected, or indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements. For ordinary skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0050] In the present application, unless explicitly defined and limited, the first feature "on" or "under" the second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the first feature "on", "above" and "above" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "under", "below" and "below" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0051] In the description of the present embodiment, the terms "up", "down", "right", and other orientation or position relationship are based on the orientation or position relationship shown in the drawings, only for the convenience of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore cannot be understood as a limitation to the present application. In addition, the terms "first", "second" are only used to distinguish in description, and have no special meaning.

[0052] Reference is made to Figures 1-5The present application provides a super-hydrophobic microstructure gas-liquid interface tracking observation device, which comprises a placing rack 1, an experimental water tank 2, a constant-pressure water supply system 3 and an observation system 4. The experimental water tank 2 is fixedly arranged on the placing rack 1 and is horizontally arranged. The super-hydrophobic sample is placed in the experimental water tank 2. The experimental water tank 2 can provide the required working conditions for the experiment. The constant-pressure water supply system 3 is connected with the experimental water tank 2 to form a closed environment. The constant-pressure water supply system 3 can supply water for the experiment of the experimental water tank 2. The observation system 4 is arranged on the side of the placing rack 1 and can observe the position, shape and evolution process of the gas-liquid interface on the surface of the super-hydrophobic sample in the experimental water tank 2. The placing rack 1 is used to install the experimental water tank 2 and the observation system 4. The experimental water tank 2 is fixedly arranged on the placing rack 1 and is ensured to be in a horizontal state. The constant-pressure water supply system 3 is connected with the experimental water tank 2 to form a closed environment. The constant-pressure water supply system 3 can supply water for the experiment of the experimental water tank 2. The super-hydrophobic sample is arranged in the experimental water tank 2. The experimental water tank 2 can provide the required working conditions for the experiment. The observation system 4 is arranged on the side of the placing rack 1. The observation system 4 can observe the position, shape and evolution process of the gas-liquid interface on the surface of the super-hydrophobic sample in the experimental water tank 2. The super-hydrophobic microstructure gas-liquid interface tracking observation device can observe the position, shape and evolution process of the gas-liquid interface on the surface of the super-hydrophobic sample, thereby helping to explore the evolution law of the gas-liquid interface and to clarify the destruction mechanism of the gas layer.

[0053] Optionally, the experimental water tank 2 comprises an upper plate 21, a bottom plate 22, a boss gland 24 and a water prism 23. The upper plate 21 is fixedly connected with the bottom plate 22. A channel is arranged between the upper plate 21 and the bottom plate 22. The channel comprises a front end diffusion section 211, a straight groove section 212 and a rear end contraction section 213 which are sequentially communicated. The bottom plate 22 is provided with a square opening 221 which is communicated with the straight groove section 212. The boss gland 24 can close the square opening 221 and fix the super-hydrophobic sample. The water prism 23 is fixedly arranged on the upper plate 21 and is located at a position corresponding to the placement position of the super-hydrophobic sample, so as to change the light path and achieve total internal reflection on the surface of the super-hydrophobic sample. The experimental water tank 2 is detachable. The upper plate 21 and the bottom plate 22 are connected by bolts. The upper plate 21 is provided with a groove. After the upper plate 21 and the bottom plate 22 are connected, the groove and the bottom plate 22 form the channel. The channel comprises the front end diffusion section 211, the straight groove section 212 and the rear end contraction section 213 which are sequentially communicated in the water flow direction. The front end diffusion section 211 is used to make the water flow uniformly. The rear end contraction section 213 is used to maintain the stable outflow of the water flow. The front end diffusion section 211 is provided with a front end water inlet 222 which is located at the starting point of the front end diffusion section 211 and is used to supply water into the channel. The rear end contraction section 213 is provided with a rear end water outlet 223 which is located at the tail of the rear end contraction section 213 and is used to discharge water from the channel.

[0054] Optionally, a first sealing ring is arranged between the upper plate 21 and the bottom plate 22, and the first sealing ring is used to seal the channel. The first sealing ring is arranged around the channel, and can prevent water from flowing out of the channel, i.e., can prevent water from flowing out of the gap between the upper plate 21 and the bottom plate 22. The first sealing ring is a silica gel ring.

[0055] Specifically, the boss cover 24 includes a cover plate and a protrusion, the cover plate and the protrusion are fixedly connected, and the protrusion can extend into the straight channel section 212 from the square opening 221. The super-hydrophobic sample sheet is placed on the protrusion, and then the protrusion extends into the straight channel section 212 from the square opening 221, so that the super-hydrophobic sample sheet is clamped and fixed on the lower surface of the upper plate 21. The cover plate can be attached to the lower surface of the bottom plate 22, so that the cover plate can seal the square opening 221.

[0056] Optionally, a second sealing ring is arranged between the boss cover 24 and the bottom plate 22, and the second sealing ring is used to seal the square opening 221. The second sealing ring can prevent water from flowing out of the gap between the boss cover 24 and the bottom plate 22. The second sealing ring is a silica gel ring.

[0057] Specifically, the water prism 23 is a hollow structure, and the middle empty position is filled with water; the water prism 23 is adhered to the position corresponding to the position where the super-hydrophobic sample sheet is placed on the upper plate 21 by transparent glue, so as to change the light path to achieve total internal reflection on the surface of the super-hydrophobic sample sheet, i.e., the incident angle of the light ray entering the gas-liquid interface on the surface of the super-hydrophobic sample sheet after passing through the water prism 23 should be greater than 48.8°.

[0058] Optionally, the distance between the starting point of the straight channel section 212 and the front end of the square opening 221 should satisfy the formula:

[0059] L>0.057D h R e

[0060] Wherein, L is the distance between the starting point of the straight channel section 212 and the front end of the square opening 221; D h is the hydraulic diameter of the straight channel section 212; R e is the Reynolds number in the straight channel section 212, R e ≤2000.

[0061] The hydraulic diameter of the straight channel section 212 is calculated according to the formula:

[0062]

[0063] Wherein: W is the width of the straight channel section 212; H c is the height of the straight channel section 212.

[0064] Since the superhydrophobic sample is roughly located at the square opening 221, restricting the position of the square opening 221 restricts the position of the superhydrophobic sample. The front end of the square opening 221 is the end closest to the front diffuser section 211, and the starting point of the straight groove section 212 is the end connected to the front diffuser section 211. The distance L between the starting point of the straight groove section 212 and the front end of the square opening 221 is greater than 0.057D. h R e This ensures the full development of laminar flow.

[0065] The distance between the rear end of the square opening 221 and the tail end of the straight groove section 212 should be greater than or equal to 80 times the hydraulic diameter of the straight groove section 212. The rear end of the square opening 221 is the end closest to the rear converging section 213, and the tail end of the straight groove section 212 is the end connected to the rear converging section 213. The distance between the rear end of the square opening 221 and the tail end of the straight groove section 212 should be greater than or equal to 80 times the hydraulic diameter D of the straight groove section 212. h This can eliminate the influence of the wake on the flow in the front-end test area.

[0066] Optionally, the constant pressure water supply system 3 includes a constant pressure water tank 31, a micro water pump 32, a water injection pipe 33, and a return pipe 34. The input end of the micro water pump 32 is connected to the constant pressure water tank 31, and the output end of the micro water pump 32 is connected to the front diffuser section 211 through the water injection pipe 33. The two ends of the return pipe 34 are connected to the rear contraction section 213 and the constant pressure water tank 31, respectively. The micro water pump 32 is used to input water from the constant pressure water tank 31 into the experimental water tank 2. The water in the constant pressure water tank 31 passes through the water injection pipe 33, the front diffuser section 211 of the experimental water tank 2, the straight channel section 212, the rear contraction section 213, and the return pipe 34 in sequence before returning to the constant pressure water tank 31. The constant pressure water tank 31 is connected to the experimental water tank 2 and forms a closed environment, not connected to the outside world.

[0067] Optionally, the constant pressure water supply system 3 also includes a micro flow meter 35, which is installed in the water injection pipeline 33 to monitor and regulate the flow rate in the experimental water tank 2.

[0068] Optionally, a pressure sensor 37 is installed on the constant pressure water tank 31 to monitor the ambient pressure inside the constant pressure water tank 31.

[0069] Optionally, a constant pressure tank 36 is also provided above the constant pressure water tank 31. The constant pressure water tank 31 is connected to the constant pressure tank 36. The constant pressure tank 36 is used to maintain the stability of the overall closed environment pressure of the constant pressure water tank 31 and the experimental water tank 2.

[0070] Optionally, the observation system 4 comprises an industrial microscope 41, a parallel light source 42, a movable support 44, and a computer 43, the industrial microscope 41 and the parallel light source 42 are installed on the movable support 44, the industrial microscope 41 and the parallel light source 42 can move along the horizontal direction or the vertical direction on the movable support 44, the industrial microscope 41 and the parallel light source 42 are both provided with a polarizer, the movable support 44 is arranged on the placing rack 1, the industrial microscope 41 is connected with the computer 43, and the computer 43 is used for displaying the position and shape information of the gas-liquid interface on the surface of the super-hydrophobic sample sheet and displaying the evolution process of the gas-liquid interface.

[0071] Optionally, the movable support 44 comprises a first vertical guide rail 441, a second vertical guide rail 442, a horizontal guide rail 443, a first vertical sliding block 444, a second vertical sliding block 445, a first horizontal sliding block 446, and a second horizontal sliding block 447, the first vertical sliding block 444 and the second vertical sliding block 445 are connected with the industrial microscope 41 and the parallel light source 42 respectively, the first vertical sliding block 444 and the second vertical sliding block 445 are slidingly arranged on the first vertical guide rail 441 and the second vertical guide rail 442 respectively, and the first horizontal sliding block 446 and the second horizontal sliding block 447 are fixedly connected with the first vertical guide rail 441 and the second vertical guide rail 442 respectively, and the first horizontal sliding block 446 and the second horizontal sliding block 447 are slidingly arranged on the horizontal guide rail 443.

[0072] The industrial microscope 41 can move along the extension direction of the first vertical guide rail 441 through the first vertical sliding block 444, and the parallel light source 42 can move along the extension direction of the second vertical guide rail 442 through the second vertical sliding block 445. The industrial microscope 41 can move along the extension direction of the horizontal guide rail 443 through the first vertical guide rail 441 and the first horizontal sliding block 446, and the parallel light source 42 can move along the extension direction of the horizontal guide rail 443 through the second vertical guide rail 442 and the second horizontal sliding block 447. The first vertical guide rail 441 and the second vertical guide rail 442 both extend along the vertical direction, and the horizontal guide rail 443 extends along the horizontal direction, so that the industrial microscope 41 and the parallel light source 42 can move along the horizontal direction or the vertical direction. The industrial microscope 41 and the parallel light source 42 can be fixed at the appropriate positions after moving to the appropriate positions.

[0073] The industrial microscope 41 is connected with the first vertical sliding block 444 through the embedded thread mode, and the parallel light source 42 is also connected with the second vertical sliding block 445 through the embedded thread mode, the embedded thread connection mode can realize rotation and fixation at any rotation angle. The industrial microscope 41 and the parallel light source 42 can be rotated to any position and fixed, so as to realize the adjustment of the experimental shooting window.

[0074] The industrial microscope 41 and the parallel light source 42 are both provided with a polarizer, so as to realize the adjustment of the polarization state of light.

[0075] The industrial microscope 41 is connected with the computer 43 through a data transmission line, and the computer 43 can display the position and shape information of the gas-liquid interface to show the evolution process of the gas-liquid interface.

[0076] The application further provides a super-hydrophobic microstructure gas-liquid interface tracking observation method.

[0077] S1: The super-hydrophobic sample sheet is placed on the boss cover 24, and the boss cover 24 is inserted into the groove from the square opening 221, so that the super-hydrophobic sample sheet is clamped between the upper plate 21 and the boss cover 24.

[0078] The boss of the boss cover 24 can be inserted into the straight groove section 212 from the square opening 221, the super-hydrophobic sample sheet is placed on the boss, and then the boss is inserted into the straight groove section 212 from the square opening 221, so that the super-hydrophobic sample sheet is clamped and fixed on the lower surface of the upper plate 21, and the cover plate of the boss cover 24 can be attached to the lower surface of the bottom plate 22, so that the cover plate can close the square opening 221.

[0079] S2: The constant-pressure water supply system 3 is connected with the experimental water tank 2, and water is injected into the constant-pressure water supply system 3.

[0080] The water injection pipeline 33 of the constant-pressure water supply system 3 is connected with the front-end water inlet 222 of the experimental water tank 2 located in the front-end diffusion section 211, and the backflow pipeline 34 of the constant-pressure water supply system 3 is connected with the rear-end water outlet 223 of the experimental water tank 2 located in the rear-end contraction section 213.

[0081] S3: The constant-pressure water supply system 3 slowly supplies water to the experimental water tank 2 to eliminate the air bubbles in the experimental water tank 2.

[0082] The pressure in the constant-pressure water tank 31 is adjusted to meet the required pressure, and the micro water pump 32 is opened to inject water into the experimental water tank 2, and the slow injection can prevent the existence of air bubbles in the experimental water tank 2.

[0083] S4: The positions of the industrial microscope 41 and the parallel light source 42 are adjusted, so that the light path passes through the water prism 23 and reaches the gas-liquid interface on the surface of the super-hydrophobic sample sheet, and can form total internal reflection, the polarizer is adjusted, and the light is adjusted to the required polarization state.

[0084] The positions and angles of the industrial microscope 41 and the parallel light source 42 are adjusted, so that the light path passes through the water prism 23 and reaches the gas-liquid interface on the surface of the super-hydrophobic sample sheet, and can form total internal reflection, and the light is adjusted to the required polarization state by adjusting the polarizer.

[0085] S5: The flow rate of water in the experimental water tank 2 is adjusted to the set flow rate.

[0086] The flow rate in the experimental tank 2 is monitored and regulated by a micro flow meter 35.

[0087] S6: The position, shape and evolution of the air-liquid interface on the superhydrophobic sample surface are photographed and recorded.

[0088] The position, shape and evolution of the air-liquid interface on the superhydrophobic sample surface are photographed by the industrial microscope 41 and displayed and recorded by the computer 43.

[0089] Obviously, the above disclosed embodiments of the present application are only used to help explain the present application. The embodiments do not describe all the details and do not limit the present application to the specific embodiments. According to the content of the present specification, many modifications and changes can be made. The present specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present application, so that those skilled in the art can well understand and utilize the present application. It is not necessary and impossible to exhaust all the embodiments. Any modification, equivalent replacement and improvement within the spirit and principle of the present application shall be included in the protection scope of the claims of the present application.

Claims

1. An ultra-hydrophobic microstructure gas-liquid interface tracking observation device, characterized by, The utility model relates to a super-hydrophobic sample surface gas-liquid interface observation device, which comprises: a rack (1); an experimental water tank (2) fixedly arranged on the rack (1) and horizontally arranged, wherein a super-hydrophobic sample is arranged in the experimental water tank (2), and the experimental water tank (2) can provide a working condition required by an experiment; a constant-pressure water supply system (3) connected with the experimental water tank (2) to form a closed environment, wherein the constant-pressure water supply system (3) can provide experimental water for the experimental water tank (2); an observation system (4) arranged on a side of the rack (1) and capable of observing a position, shape and evolution process of a gas-liquid interface on the surface of the super-hydrophobic sample in the experimental water tank (2); the experimental water tank (2) comprises an upper plate (21), a bottom plate (22), a boss cover (24) and a water prism (23), the upper plate (21) is fixedly connected with the bottom plate (22), a channel is arranged between the upper plate (21) and the bottom plate (22), the channel comprises a front-end diffusion section (211), a straight channel section (212) and a rear-end contraction section (213) which are sequentially communicated, the bottom plate (22) is provided with a square opening (221), the square opening (221) is communicated with the straight channel section (212), the boss cover (24) can seal the square opening (221) and fix the super-hydrophobic sample, and the water prism (23) is fixedly arranged on the upper plate (21) and located at a position corresponding to a placement position of the super-hydrophobic sample, so as to change an optical path and achieve total internal reflection on the surface of the super-hydrophobic sample; a distance between a starting point of the straight channel section (212) and a front end of the square opening (221) should satisfy a formula: wherein, is the distance from the start of the straight slot section (212) to the front end of the square opening (221); is the hydraulic diameter of the straight slot section (212); is the Reynolds number in the straight slot section (212), ; a hydraulic diameter of the straight channel section (212) is calculated according to a formula: wherein: is the width of the straight slot section (212); is the height of the straight slot section (212). a distance between a rear end of the square opening (221) and a tail of the straight channel section (212) should be greater than or equal to 80 times of the hydraulic diameter of the straight channel section (212).

2. The superhydrophobic microstructured gas-liquid interface tracking observation device of claim 1, wherein: a first sealing ring is arranged between the upper plate (21) and the bottom plate (22) and used for sealing the channel.

3. The superhydrophobic microstructured gas-liquid interface tracking observation device of claim 1, wherein: a second sealing ring is arranged between the boss cover (24) and the bottom plate (22) and used for sealing the square opening (221).

4. The superhydrophobic microstructured gas-liquid interface tracking observation device of claim 1, wherein: the constant-pressure water supply system (3) comprises a constant-pressure water tank (31), a micro water pump (32), a water injection pipeline (33) and a backflow pipeline (34), an input end of the micro water pump (32) is communicated with the constant-pressure water tank (31), an output end of the micro water pump (32) is communicated with the front-end diffusion section (211) through the water injection pipeline (33), and two ends of the backflow pipeline (34) are respectively communicated with the rear-end contraction section (213) and the constant-pressure water tank (31).

5. The superhydrophobic microstructured gas-liquid interface tracking observation device of claim 4, wherein: the constant-pressure water supply system (3) further comprises a micro flowmeter (35) arranged in the water injection pipeline (33) and used for monitoring and regulating a flow in the experimental water tank (2).

6. The superhydrophobic microstructured gas-liquid interface tracking observation device of claim 4, wherein: The constant pressure water supply system (3) further comprises a constant pressure air tank (36), the constant pressure water tank (31) is connected with the constant pressure air tank (36), and the constant pressure air tank (36) can maintain the pressure of the closed environment.

7. The superhydrophobic microstructured gas-liquid interface tracking observation device of claim 1, wherein: The observation system (4) comprises an industrial microscope (41), a parallel light source (42), a movable support (44) and a computer (43), the industrial microscope (41) and the parallel light source (42) are both installed on the movable support (44), the industrial microscope (41) and the parallel light source (42) can move in the horizontal direction or the vertical direction on the movable support (44), the industrial microscope (41) and the parallel light source (42) are both provided with a polarizer, the movable support (44) is arranged on the placing rack (1), the industrial microscope (41) is connected with the computer (43), and the computer (43) is used for displaying the position and shape information of the gas-liquid interface on the surface of the super-hydrophobic sample piece and displaying the evolution process of the gas-liquid interface.

8. A superhydrophobic microstructure gas-liquid interface tracking observation method, characterized by, The super-hydrophobic microstructure gas-liquid interface tracking observation device of any one of claims 1-7, wherein the experimental water tank (2) comprises an upper plate (21), a bottom plate (22), a boss gland (24) and a water prism (23), the bottom plate (22) is provided with a square opening (221), and the upper plate (21) and the bottom plate (22) have a channel therebetween; the observation system (4) comprises an industrial microscope (41), a parallel light source (42), a movable support (44) and a computer (43), and the industrial microscope (41) and the parallel light source (42) are both provided with a polarizer; The super-hydrophobic microstructure gas-liquid interface tracking observation method comprises: S1: placing the super-hydrophobic sample piece on the boss gland (24), and extending the boss gland (24) from the square opening (221) into the channel, so that the super-hydrophobic sample piece is clamped between the upper plate (21) and the boss gland (24); S2: connecting the constant pressure water supply system (3) with the experimental water tank (2), and injecting water into the constant pressure water supply system (3); S3: slowly supplying water to the experimental water tank (2) by the constant pressure water supply system (3) to eliminate air bubbles in the experimental water tank (2); S4: adjusting the positions of the industrial microscope (41) and the parallel light source (42) so that the light path passes through the water prism (23) and reaches the gas-liquid interface on the surface of the super-hydrophobic sample piece and can form total internal reflection, adjusting the polarizers to adjust the polarization state of the light to the required polarization state; S5: adjusting the flow rate of water in the experimental water tank (2) to a set flow rate; S6: photographing and recording the position, shape and evolution process of the gas-liquid interface on the surface of the super-hydrophobic sample piece.

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