A device and method for measuring normal and tangential interaction forces between adhesive particles

Abstract

This invention relates to the field of viscous particle property measurement technology, and discloses a device and method for measuring the normal and tangential interaction forces between viscous particles. The device includes: a base, on which a first three-axis moving platform and a second three-axis moving platform are mounted; a first force sensor and a second force sensor are mounted on the first three-axis moving platform; the first force sensor detects the force on the lower particle in the vertical direction, and the second force sensor detects the force on the lower particle in the horizontal direction; the first and second three-axis moving platforms drive the upper and lower particles to move; and a syringe is used to inject liquid between the upper and lower particles to form a liquid bridge or a solid bridge. After injecting liquid to form a liquid bridge or solid bridge between the upper and lower particles, the forces on the lower particle in the vertical and horizontal directions are detected by the first and second force sensors, thereby measuring the normal and tangential interaction forces between the viscous particles.

Description

Technical Field

[0001] This invention relates to the field of viscous particle property measurement technology, and in particular to a device and method for measuring the normal and tangential interaction forces between viscous particles. Background Technology

[0002] When a small amount of liquid is present on the surface of particles, the liquid or solid bridges formed between the particles will cause adhesion between them, resulting in properties different from those of dry particles. For example, the angle of stacking of dry sand will not exceed its angle of repose, while wet sand can be molded into various shapes. The presence of liquid causes capillary action between particles, thus significantly improving their mechanical stability. In the gas-phase polyethylene process, if the reactor does not dissipate heat in time, the surface temperature of the polyethylene particles will rise, causing partial melting. When the particles come into contact, the polymer molecular chains become sticky, forming solid bridges, which ultimately leads to particle agglomeration and affects production. Therefore, studying the interparticle interaction processes, such as the formation of liquid or solid bridges, is of great significance.

[0003] Under applied force, the motion between viscous particles mainly includes two types: tension and shear. Under tension, viscous particles move along the normal direction, and adhesion exists only in the normal direction. Under shear, the axisymmetric structure between viscous particles is disrupted, resulting in tangential adhesive forces parallel to the contact interface. Simultaneously, the presence of liquid or solid bridges between particles ensures that normal adhesive forces still exist in the direction perpendicular to the contact interface. The adhesion mechanism between particles is complex, influenced by the coupling of multiple factors such as particle spacing, shear force, liquid properties (surface tension, volume, and viscosity, etc.) and solid properties (such as wettability, roughness, and chemical inhomogeneity, etc.).

[0004] Currently, commonly used measurement methods include atomic force microscopy (AFM), surface force apparatus (SFA), microbalance, and centrifugation. These methods are only applicable to the interaction between particles and the surface of an object, and cannot measure the normal and tangential adhesion forces between sticky particles. Furthermore, the test conditions are mostly static and quasi-static, and cannot measure the dynamic changes of sticky particles under different particle spacings and shear forces.

[0005] In view of this, how to provide a device and method for measuring the normal and tangential interaction forces between viscous particles is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a device and method for measuring the normal and tangential interaction forces between viscous particles, so as to solve the problems existing in the prior art.

[0007] To achieve the above objectives, the present invention provides a device for measuring the normal and tangential interaction forces between viscous particles, comprising: A base is provided, on which a first three-axis moving platform and a second three-axis moving platform are provided. A first force sensor and a second force sensor are provided on the first three-axis moving platform. The sensing end of the first force sensor is provided with a first mounting base, and the first mounting base is provided with a first mounting groove for fixing the lower particle. The sensing end of the second force sensor is connected to the lower particle. The first force sensor is used to detect the magnitude of the force on the lower particle in the vertical direction, and the second force sensor is used to detect the magnitude of the force on the lower particle in the horizontal direction. A second mounting base is disposed on a second three-axis moving platform. The second mounting base is provided with a second mounting groove for fixing an upper particle, which is located above the lower particle. The first and second three-axis moving platforms are used to drive the upper and lower particles to move. The syringe is used to inject liquid between the upper and lower particles and form a liquid bridge or solid bridge when the first and second three-axis moving platforms drive the upper and lower particles to approach each other. A high-speed microscope camera is mounted on a base, with its image acquisition end facing the upper and lower particles.

[0008] Furthermore, the second force sensor is mounted on the slider, which is slidably disposed on the first three-axis moving platform. The slider is connected to a drive motor, which is used to drive the slider to move closer to or away from the first mounting base.

[0009] Furthermore, the upper particle is fixed in the first mounting groove and connected to the second force sensor by adhesive; the lower particle is fixed in the second mounting groove by adhesive.

[0010] Furthermore, the high-speed microscope camera includes a first high-speed microscope camera and a second high-speed microscope camera. The first high-speed microscope camera is arranged at the front end of the first three-axis moving platform, and the second high-speed microscope camera is arranged on the left side of the first three-axis moving platform.

[0011] Furthermore, it also includes: A hollow LED cold light source is disposed on the first three-axis moving platform and located between the first high-speed microscope camera and the first mounting base; A flat LED cold light source is mounted on the base and located on the right side of the first three-axis moving platform.

[0012] Furthermore, the first high-speed microscope camera is mounted on the first tripod, the second high-speed microscope camera is mounted on the second tripod, and the flat LED cold light source is mounted on the third tripod.

[0013] Furthermore, the second three-axis moving platform is mounted on a Z-axis unidirectional moving platform, which is mounted on a base and is used to drive the second three-axis moving platform to move up and down in the vertical direction.

[0014] Furthermore, it also includes: A support platform is provided, wherein the first three-axis moving platform is mounted on the support platform, and the support platform is mounted on the base.

[0015] This invention also provides a method for measuring the normal and tangential interaction forces between viscous particles, using a device for measuring the normal and tangential interaction forces between viscous particles, comprising the following steps: S1: Fix the upper particle in the second mounting groove and the lower particle in the first mounting groove. Drive the second force sensor to approach the first mounting groove by the drive motor. When the sensing end of the second force sensor comes into contact with the lower particle, connect the sensing end of the second force sensor to the lower particle by adhesive. S2: Drive the upper and lower particles to move using the first and second three-axis moving platforms, so that the upper and lower particles are close to each other and arranged coaxially in the vertical direction; adjust the positions of the first and second high-speed microscope cameras so that their image acquisition ends face the upper and lower particles; based on the images acquired by the first and second high-speed microscope cameras, drive the upper and lower particles to move again using the first and second three-axis moving platforms, so that the upper and lower particles are close to each other and arranged coaxially in the vertical direction, with the distance between the upper and lower particles being the initial distance; S3: Inject liquid between the upper and lower particles using a syringe to form a liquid bridge or solid bridge. After the detection data from the first and second force sensors stabilize, record the magnitude of the force on the particle in the vertical direction. F 1-1 Record the magnitude of the force on the particle in the horizontal direction. F 1-2 ; S4: Based on the images acquired by the first and second high-speed microscope cameras, the upper and lower particles are driven to move vertically using the first and second three-axis moving platforms, making the distance between the upper and lower particles zero. The upper particle is then moved vertically upwards to a first preset position, and then horizontally to a second preset position. After the detection data from the first and second force sensors stabilize, the magnitude of the force acting on the particle in the vertical direction is recorded. F 2-1 Record the magnitude of the force on the particle in the horizontal direction. F 2-2 .

[0016] Furthermore, the method includes the following steps: acquiring images of the interaction between the upper and lower particles using a first high-speed microscope camera and a second high-speed microscope camera, performing binarization processing using ImageView software, and then using MATLAB to extract the contour of the interparticle interaction structure, obtaining the neck width, contact radius, and half-filling angle based on the interparticle interaction structure contour; The apparent contact angle is obtained by using the AutoCAD-assisted tangent method: connect the center of the lower particle and the contact point between the lower particle and the liquid bridge or solid bridge, and draw its tangent; then start from the contact point between the lower particle and the liquid bridge or solid bridge and form a boundary line along the interface of the liquid bridge. The angle between the tangent and the boundary line is the apparent contact angle.

[0017] Furthermore, before the upper and lower particles are installed, they are cleaned using an ultrasonic cleaner and then dried.

[0018] The present invention discloses the following technical effects: 1. The upper and lower particles are coaxially arranged by driving the first and second three-axis moving platforms, and the images of the upper and lower particles are acquired by a high-speed microscope camera to improve the arrangement accuracy of the upper and lower particles; after liquid is injected between the upper and lower particles to form a liquid bridge or solid bridge, the magnitude of the force on the lower particle in the vertical and horizontal directions is detected by the first and second force sensors, thereby measuring the normal and tangential interaction forces between the viscous particles.

[0019] 2. The upper and lower particles can be of the same or different particle sizes. During the installation of the lower particles, the slider can be driven by the drive motor to move closer to or away from the first mounting base, so that the sensing end of the second force sensor is connected to the lower particles, thereby realizing the measurement of the normal and tangential interaction forces of lower particles of different sizes.

[0020] 3. After acquiring images of the interaction between the upper and lower particles using the first and second high-speed microscope cameras, the structural contour of the interparticle interaction, as well as parameters such as neck width, contact radius, and half-fill angle, can be obtained through image processing methods. This allows for the interpretation of the measured changes in the normal and tangential interaction forces between the viscous particles. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the interaction structure between two particles (taking a liquid bridge as an example) under static and shear conditions. Figure 3 This document describes the parameters for neck width, contact radius, contact angle, and half-fill angle obtained based on the interparticle interaction structure profile. Figure 4 The graph shows the changes in normal and tangential forces over time when tension and shear exist between particles. Figure 5 This is a graph showing the variation of normal and tangential forces with tangential distance when there is tension and shear between particles; Figure 6 The graph shows the variation of the magnitude of the normal and tangential forces under different liquid volumes; Figure 7 The magnitudes of normal and tangential forces vary under different particle spacings; The components include: 1. Base; 2. First tripod; 3. First high-speed microscope; 4. Support platform; 5. First three-axis moving platform; 6. Hollow LED cold light source; 7. Second tripod; 8. Second high-speed microscope; 9. Syringe; 10. Second three-axis moving platform; 11. Second mounting base; 12. Upper particle; 13. Lower particle; 14. First force sensor; 15. Second force sensor; 16. Third tripod; 17. Flat LED cold light source; 18. Z-axis unidirectional moving platform. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Those skilled in the art will understand that the term "comprising" as used in this application means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements present. Furthermore, "connected" or "coupled" as used herein can include wireless connections or wireless coupling. The term "and / or" as used herein includes all or any unit and all combinations of one or more associated listed items.

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] like Figures 1 to 7 As shown, this embodiment of the invention provides a device for measuring the normal and tangential interaction forces between viscous particles, comprising: A base 1 is provided, on which a first three-axis moving platform 5 and a second three-axis moving platform 10 are provided. A first force sensor 14 and a second force sensor 15 are provided on the first three-axis moving platform 5. The sensing end of the first force sensor 14 is provided with a first mounting base, and the first mounting base is provided with a first mounting groove for fixing the lower particle 13. The sensing end of the second force sensor 15 is connected to the lower particle 13. The first force sensor 14 is used to detect the magnitude of the force (i.e., normal force) on the lower particle 13 in the vertical direction, and the second force sensor 15 is used to detect the magnitude of the force (i.e., tangential force) on the lower particle 13 in the horizontal direction. The second mounting base 11 is disposed on the second three-axis moving platform 10. The second mounting base 11 is provided with a second mounting groove for fixing the upper particle 12, which is located above the lower particle 13. The first three-axis moving platform 5 and the second three-axis moving platform 10 are used to drive the upper particle 12 and the lower particle 13 to move. When the first three-axis moving platform 5 and the second three-axis moving platform 10 drive the upper particle 12 and the lower particle 13 to approach each other, the syringe 9 is used to inject liquid between the upper particle 12 and the lower particle 13 to form a liquid bridge or solid bridge. A high-speed microscope camera is mounted on the base 1, with its image acquisition end facing the upper particle 12 and the lower particle 13.

[0027] In this embodiment, at least one of the first three-axis moving platform 5 and the second three-axis moving platform 10 has a nanometer-level moving accuracy. The first force sensor 14 and the second force sensor 15 both have a microNewton-level accuracy.

[0028] In this embodiment, the second force sensor 15 is mounted on the slider, which is slidably mounted on the first three-axis moving platform 5. The slider is connected to the drive motor, which is used to drive the slider to move closer to or away from the first mounting base.

[0029] In this embodiment, the upper particle 12 is fixed in the first mounting groove and connected to the second force sensor 15 by adhesive; the lower particle 13 is fixed in the second mounting groove by adhesive.

[0030] In this embodiment, the high-speed microscope camera includes a first high-speed microscope camera 3 and a second high-speed microscope camera 8. The first high-speed microscope camera 3 is arranged at the front end of the first three-axis moving platform 5, and the second high-speed microscope camera 8 is arranged on the left side of the first three-axis moving platform 5.

[0031] In this embodiment, it also includes: A hollow LED cold light source 6 is mounted on the first three-axis moving platform 5 and located between the first high-speed microscope camera 3 and the first mounting base; A flat LED cold light source 17 is mounted on the base 1 and located on the right side of the first three-axis moving platform 5.

[0032] In this embodiment, the hollow LED cold light source 6 can avoid obstructing the image acquisition circuit of the first high-speed microscope camera 3. The brightness and position of the two LED cold light sources can be adjusted according to experimental requirements.

[0033] In this embodiment, the first high-speed microscope camera 3 is mounted on the first tripod 2, the second high-speed microscope camera 8 is mounted on the second tripod 7, and the flat LED cold light source 17 is mounted on the third tripod 16.

[0034] In this embodiment, the second three-axis moving platform 10 is disposed on the Z-axis unidirectional moving platform 18, which is disposed on the base 1 and is used to drive the second three-axis moving platform 10 to move up and down in the vertical direction.

[0035] In this embodiment, it also includes: Support platform 4, first three-axis moving platform 5 is set on support platform 4, support platform 4 is set on base 1.

[0036] In this embodiment, the upper particle 12 and the lower particle 13 are selected as particles with a particle size of micrometer or millimeter. The material can be glass, plastic, metal, etc. The upper particle 12 and the lower particle 13 can be the same particle size or different particle sizes. In the initial state, the upper particle 12 and the lower particle 13 can be kept coaxial in the vertical direction.

[0037] This invention also provides a method for measuring the normal and tangential interaction forces between viscous particles, using a device for measuring the normal and tangential interaction forces between viscous particles, comprising the following steps: S1: The upper particle 12 is fixed in the second mounting groove by adhesive, and the lower particle 13 is fixed in the first mounting groove by adhesive. The second force sensor 15 is driven to approach the first mounting groove by the drive motor. When the sensing end of the second force sensor 15 comes into contact with the lower particle 13, the sensing end of the second force sensor 15 is connected to the lower particle 13 by adhesive. S2: The upper particle 12 and lower particle 13 are moved by the first three-axis moving platform 5 and the second three-axis moving platform 10, so that the upper particle 12 and lower particle 13 are close to each other and arranged coaxially in the vertical direction. In this process, the Z-axis unidirectional moving platform 18 can also be used for auxiliary movement. First, coarse adjustment is made by the large-stroke Z-axis unidirectional moving platform 18, and then fine adjustment is made by the first three-axis moving platform 5 and the second three-axis moving platform 10. After fine adjustment, the upper particle 12 and lower particle 13 are roughly coaxially arranged; adjust the position of the first high-speed microscope camera 3 and the second high-speed microscope camera 8. The image acquisition ends of the first high-speed microscope camera 3 and the second high-speed microscope camera 8 are positioned so that they face the upper particle 12 and the lower particle 13. Based on the images acquired by the first high-speed microscope camera 3 and the second high-speed microscope camera 8, the upper particle 12 and the lower particle 13 are moved again by the first three-axis moving platform 5 and the second three-axis moving platform 10, so that the upper particle 12 and the lower particle 13 are close to each other and arranged coaxially in the vertical direction. The above steps can ensure that the upper particle 12 and the lower particle 13 are arranged coaxially, improve the operation accuracy, and the distance between the upper particle 12 and the lower particle 13 is the initial distance. S3: Confirm whether the first force sensor 14 and the second force sensor 15 are at the same temperature as the ambient temperature. If not, adjust the temperature of the first force sensor 14 and the second force sensor 15 to the ambient temperature using external heating or cooling equipment. Inject liquid between the upper particle 12 and the lower particle 13 using syringe 9 to form a liquid bridge or solid bridge. After the detection data of the first force sensor 14 and the second force sensor 15 stabilize, record the magnitude of the force on particle 13 in the vertical direction. F 1-1 Record the magnitude of the force on particle 13 in the horizontal direction. F 1-2 ; S4: Based on the images acquired by the first high-speed microscope camera 3 and the second high-speed microscope camera 8, the upper particle 12 and the lower particle 13 are driven to move vertically through the first three-axis moving platform 5 and the second three-axis moving platform 10, so that the distance between the upper particle 12 and the lower particle 13 is 0, and the initial distribution of the droplets is achieved; then the upper particle 12 is moved vertically upward to the first preset position, and then moved horizontally to the second preset position. After the detection data of the first force sensor 14 and the second force sensor 15 stabilize, the magnitude of the force on the particle 13 in the vertical direction is recorded. F 2-1 Record the magnitude of the force on particle 13 in the horizontal direction. F 2-2 .

[0038] The normal and tangential interaction forces between viscous particles can be measured by calculating the changes in the magnitude of the forces acting on the lower particle 13 in the vertical and horizontal directions. It should be noted that when liquid is injected between the upper particle 12 and the lower particle 13 to form a solid bridge, the bridge will suddenly break as the distance between them changes. At the time of breakage, the magnitude of the forces acting on the lower particle 13 in the vertical and horizontal directions will change significantly.

[0039] After the above steps are completed, the upper particle 12 can be moved in the opposite direction in the vertical or horizontal direction to complete one motion cycle. At the same time, the magnitude of the force on particle 13 in the vertical direction and the magnitude of the force on lower particle 13 in the horizontal direction are recorded to form a curve of the force magnitude changing with time.

[0040] In this embodiment, different volumes of the injected liquid can also be set, such as 0.2 μL, 0.4 μL, 0.6 μL, 0.8 μL, 1.0 μL, 1.2 μL, 1.4 μL, 1.6 μL, 1.8 μL, and 2.0 μL. The normal and tangential interaction forces between viscous particles are measured under different liquid volumes.

[0041] In this embodiment, the following steps are also included: acquiring images of the interaction between the upper particle 12 and the lower particle 13 using a first high-speed microscope camera 3 and a second high-speed microscope camera 8; performing binarization processing using ImageView software; then using MATLAB to extract the contour of the interparticle interaction structure; and obtaining the neck width, contact radius, and half-fill angle, etc., based on the interparticle interaction structure contour. Figure 3 As shown, where, R Indicates particle radius, W d Indicates the contact radius. R in Indicates the width of the neck. β Indicates a half-filled corner. θ Indicates the contact angle.

[0042] The apparent contact angle is obtained by using the AutoCAD-assisted tangent method: connect the center of the lower particle 13 and the contact point between the lower particle 13 and the liquid bridge or solid bridge, and draw its tangent; then start from the contact point between the lower particle 13 and the liquid bridge or solid bridge and form a boundary line along the interface of the liquid bridge. The angle between the tangent and the boundary line is the apparent contact angle.

[0043] In this embodiment, before the upper particle 12 and the lower particle 13 are installed, the upper particle 12 and the lower particle 13 are cleaned by an ultrasonic cleaner and then dried.

[0044] In this embodiment, schematic diagrams of the interaction structure between two particles (taking a liquid bridge as an example) under static and shear conditions are shown below. Figure 2As shown, where F n1 , F n2 For normal force, F c1 , F c2 For tangential forces; when tension and shear exist between particles, the normal and tangential forces change with the time of motion and the tangential distance, as shown in the figure. Figure 4 and Figure 5 As shown; the magnitudes of the normal and tangential forces vary under different liquid volumes as follows: Figure 6 As shown; the magnitudes of normal and tangential forces vary under different particle spacings as follows Figure 7 As shown in the figure. The results above demonstrate that this embodiment can effectively measure the normal and tangential interaction forces between viscous particles.

[0045] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0046] 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 number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0047] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the connection between two components. The term refers to the connection between parts or the interaction between two elements, unless otherwise explicitly defined. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0048] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A device for measuring the normal and tangential interaction forces between viscous particles, characterized in that, include: A base (1) is provided with a first three-axis moving platform (5) and a second three-axis moving platform (10). A first force sensor (14) and a second force sensor (15) are provided on the first three-axis moving platform (5). The sensing end of the first force sensor (14) is provided with a first mounting seat. The first mounting seat is provided with a first mounting groove. The first mounting groove is used to fix the lower particle (13). The sensing end of the second force sensor (15) is connected to the lower particle (13). The first force sensor (14) is used to detect the magnitude of the force on the lower particle (13) in the vertical direction. The second force sensor (15) is used to detect the magnitude of the force on the lower particle (13) in the horizontal direction. The second mounting base (11) is disposed on the second three-axis moving platform (10). The second mounting base (11) is provided with a second mounting groove, which is used to fix the upper particle (12). The upper particle (12) is located above the lower particle (13). The first three-axis moving platform (5) and the second three-axis moving platform (10) are used to drive the upper particle (12) and the lower particle (13) to move. The syringe (9) is used to inject liquid between the upper particle (12) and the lower particle (13) and form a liquid bridge or solid bridge when the first three-axis moving platform (5) and the second three-axis moving platform (10) drive the upper particle (12) and the lower particle (13) to approach each other. A high-speed microscope camera is mounted on a base (1), with its image acquisition end facing the upper particle (12) and the lower particle (13).

2. The device for measuring the normal and tangential interaction forces between viscous particles according to claim 1, characterized in that, The second force sensor (15) is mounted on the slider, which is slidably mounted on the first three-axis moving platform (5). The slider is connected to a drive motor, which is used to drive the slider to move closer to or away from the first mounting base.

3. The device for measuring the normal and tangential interaction forces between viscous particles according to claim 2, characterized in that, The upper particle (12) is fixed in the first mounting groove and connected to the second force sensor (15) by adhesive; the lower particle (13) is fixed in the second mounting groove by adhesive.

4. The device for measuring the normal and tangential interaction forces between viscous particles according to claim 3, characterized in that, The high-speed microscope camera includes a first high-speed microscope camera (3) and a second high-speed microscope camera (8). The first high-speed microscope camera (3) is arranged at the front end of the first three-axis moving platform (5), and the second high-speed microscope camera (8) is arranged on the left side of the first three-axis moving platform (5).

5. The device for measuring the normal and tangential interaction forces between viscous particles according to claim 4, characterized in that, Also includes: A hollow LED cold light source (6) is disposed on the first three-axis moving platform (5) and located between the first high-speed microscope (3) and the first mounting base; A flat LED cold light source (17) is set on the base (1) and located on the right side of the first three-axis moving platform (5).

6. The device for measuring the normal and tangential interaction forces between viscous particles according to claim 5, characterized in that, The first high-speed microscope (3) is mounted on the first tripod (2), the second high-speed microscope (8) is mounted on the second tripod (7), and the flat LED cold light source (17) is mounted on the third tripod (16).

7. The device for measuring the normal and tangential interaction forces between viscous particles according to claim 5, characterized in that, The second three-axis moving platform (10) is mounted on the Z-axis unidirectional moving platform (18), which is mounted on the base (1) and is used to drive the second three-axis moving platform (10) to move up and down in the vertical direction.

8. The device for measuring the normal and tangential interaction forces between viscous particles according to claim 5, characterized in that, Also includes: Support platform (4), the first three-axis moving platform (5) is set on support platform (4), and support platform (4) is set on base (1).

9. A method for measuring the normal and tangential interaction forces between viscous particles, characterized in that, The application of the measuring device for normal and tangential interaction forces between viscous particles according to any one of claims 5-8 includes the following steps: S1: Fix the upper particle (12) in the second mounting groove and fix the lower particle (13) in the first mounting groove. Drive the second force sensor (15) to approach the first mounting groove by the drive motor. When the sensing end of the second force sensor (15) comes into contact with the lower particle (13), connect the sensing end of the second force sensor (15) to the lower particle (13) by adhesive. S2: Drive the upper particle (12) and lower particle (13) to move through the first three-axis moving platform (5) and the second three-axis moving platform (10), so that the upper particle (12) and lower particle (13) are close to each other and arranged coaxially in the vertical direction; adjust the position of the first high-speed microscope (3) and the second high-speed microscope (8) so that the image acquisition ends of the first high-speed microscope (3) and the second high-speed microscope (8) face the upper particle (12) and lower particle (13); according to the images acquired by the first high-speed microscope (3) and the second high-speed microscope (8), drive the upper particle (12) and lower particle (13) to move again through the first three-axis moving platform (5) and the second three-axis moving platform (10), so that the upper particle (12) and lower particle (13) are close to each other and arranged coaxially in the vertical direction, and the distance between the upper particle (12) and the lower particle (13) is the initial distance; S3: Inject liquid between the upper particle (12) and the lower particle (13) using a syringe (9) to form a liquid bridge or solid bridge. After the detection data from the first force sensor (14) and the second force sensor (15) stabilize, record the magnitude of the force on the lower particle (13) in the vertical direction. F 1-1 Record the magnitude of the force on particle (13) in the horizontal direction. F 1-2 ; S4: Based on the images acquired by the first high-speed microscope (3) and the second high-speed microscope (8), the upper particle (12) and the lower particle (13) are driven to move vertically by the first three-axis moving platform (5) and the second three-axis moving platform (10) so that the distance between the upper particle (12) and the lower particle (13) is 0. Then, the upper particle (12) is moved vertically upward to the first preset position, and then the upper particle (12) is moved horizontally to the second preset position. After the detection data of the first force sensor (14) and the second force sensor (15) stabilize, the magnitude of the force on the lower particle (13) in the vertical direction is recorded. F 2-1 Record the magnitude of the force on particle (13) in the horizontal direction. F 2-2 .

10. A method for measuring the normal and tangential interaction forces between viscous particles according to claim 9, characterized in that, It also includes the following steps: Images of the interaction between the upper particle (12) and the lower particle (13) are acquired by the first high-speed microscope (3) and the second high-speed microscope (8), and binarized by ImageView software. Then, the structure contour of the interaction between particles is extracted by MATLAB. The neck width, contact radius and half-filling angle are obtained based on the structure contour of the interaction between particles. The apparent contact angle is obtained by using the AutoCAD-assisted tangent method: connect the center of the lower particle (13) and the contact point between the lower particle (13) and the liquid bridge or solid bridge, and draw its tangent; then start from the contact point between the lower particle (13) and the liquid bridge or solid bridge and form a boundary line along the interface of the liquid bridge. The angle between the tangent and the boundary line is the apparent contact angle.

Images