Impact experiment device and system capable of regulating liquid drop physical property parameters and surface characteristics

Abstract

The application relates to the technical field of micro impact, and provides an impact experiment device and system capable of adjusting liquid drop physical property parameters and surface characteristics. In the device and system, a rotating telescopic shaft coaxially arranged below a syringe can rotate along the circumference while being axially telescopic, meanwhile, a cavity needle cylinder is uniformly distributed along the circumference of the rotating telescopic shaft, one different-specification drop needle head is correspondingly arranged in each cavity needle cylinder, the different-specification drop needle heads are adjusted to face the liquid outlet of the syringe along the circumference of the rotating telescopic shaft, and the drop needle head facing the liquid outlet of the syringe is engaged with or separated from the liquid outlet of the syringe along the axial telescopic movement of the rotating telescopic shaft. Therefore, the specification of the drop needle head is adaptively adjusted, manual replacement of the drop needle head is effectively avoided, control over liquid drops of different sizes is realized, and the drop positions of liquid drops of different sizes before and after replacement of the needle head of different specifications are effectively ensured to be the same.

Description

Technical Field

[0001] This application relates to the field of micro-impact technology, and in particular to an impact experimental apparatus and system with adjustable droplet physical parameters and surface characteristics. Background Technology

[0002] The phenomenon of droplet impact on surfaces has wide applications in various fields, including thermal management technology for high-power equipment, water mist fire suppression technology, spray cooling technology, and seawater desalination technology. Studying the complex dynamics and thermodynamics of droplet impact on surfaces based on droplet physical parameters and surface characteristics can provide theoretical basis and technical support for related industries such as fire suppression, cooling technology, internal combustion engine combustion, and spray coating.

[0003] Droplet impaction experimental devices are mainly used to observe phenomena such as droplet adhesion, rebound, and breakup. Currently, existing droplet impaction experimental devices suffer from problems such as inaccurate experimental liquid temperature, limited needle specifications, simple impact platform structure, and complex operating procedures, resulting in large experimental errors and an inability to accurately control the initial temperature, initial size, and impact position of the droplets. Summary of the Invention

[0004] The purpose of this application is to provide an impact test apparatus and system with adjustable droplet physical parameters and surface characteristics to solve or alleviate the problems existing in the prior art.

[0005] To achieve the above objectives, this application provides the following technical solution:

[0006] This application provides an impact test apparatus with adjustable droplet physical parameters and surface characteristics, including: a syringe;

[0007] The rotating telescopic shaft is coaxially mounted with the syringe and located below the syringe, and can extend and retract axially while rotating circumferentially.

[0008] The hollow syringe has evenly distributed [something] along its circumference on the axis of rotation and extension. Install one by one. The device includes several different sized dripping needles, which are adjusted circumferentially by rotating the telescopic shaft to align with the syringe outlet. The telescopic shaft also extends axially to engage or disengage the dripping needle facing the syringe outlet. It is a positive integer.

[0009] Preferably, the rotary telescopic shaft is arranged on the outer bottom surface of the syringe via a drive connecting cylinder; wherein, the inner sidewall of the drive connecting cylinder is provided with a drive cam groove along the circumferential direction, and correspondingly, a drive motor is arranged radially symmetrically at the upper end of the rotary telescopic shaft, and a drive wheel is provided at the output end of the drive motor. The drive wheel moves along the cam curve of the drive cam groove, driving the rotary telescopic shaft to rotate circumferentially while extending and retracting axially.

[0010] Preferably, according to the formula:

[0011]

[0012] Determine the cam curve of the driving cam groove; where, The trajectory of the drive wheel within the drive cam groove. The height travel of the dripping needle as it extends and retracts axially along the rotating telescopic shaft; The rotation angle of the telescopic shaft along the circumferential direction. ; The total number of hollow syringes evenly distributed circumferentially along the axis of rotation and telescopic movement. It is an even number.

[0013] Preferably, the drive wheel is driven by friction with the groove of the drive cam or by gear meshing.

[0014] Preferably, the hollow syringe is connected to the rotary telescopic shaft by a plurality of connecting rods arranged in parallel along the axial direction and extending radially.

[0015] Preferably, the upper opening of the hollow syringe is a flared structure with a larger upper opening and a smaller lower opening. A centering and positioning mounting groove is provided on the inner side wall of the flared structure along the generatrix direction, and multiple centering and positioning mounting grooves are evenly distributed circumferentially. Correspondingly, the upper end of the dripping needle is provided with an inverted conical structure that matches the flared structure, and multiple centering and positioning mounting slides that match the centering and positioning mounting grooves are evenly distributed circumferentially on the outer side wall of the inverted conical structure.

[0016] Preferably, both the centering and positioning mounting groove and the centering and positioning mounting slide rail have dovetail-shaped cross sections.

[0017] Preferably, the dripping needle includes: a positioning and mounting end and a dripping tube. The positioning and mounting end is an inverted conical structure that matches the flared mouth structure, and the outer wall is evenly distributed with multiple centering and positioning mounting slide rails that match the centering and positioning mounting grooves. The dripping tube is detachably mounted on the lower end of the positioning and mounting end. Both the positioning and mounting end and the dripping tube are provided with dripping needle holes that are coaxial with the inverted conical structure and pass through it axially.

[0018] Preferably, multiple thermocouples are evenly distributed at the bottom of the injection chamber of the syringe for real-time monitoring of the liquid temperature inside the injection chamber.

[0019] This embodiment also provides an impact test system with adjustable droplet physical parameters and surface characteristics, including any of the above-described impact test devices with adjustable droplet physical parameters and surface characteristics. The impact test device is mounted on a fixed cross slide rail to adjust its height and horizontal position relative to the surface of the adjustable test platform. The impact test system also includes:

[0020] The temperature unit is installed on the adjustable experimental platform and is used to monitor and control the temperature of the adjustable experimental platform in real time.

[0021] The light control and imaging unit includes at least a camera and a spotlight located at the same horizontal height on both sides of the adjustable experimental platform, for capturing images of the droplets falling in real time.

[0022] Beneficial effects:

[0023] In the impact test apparatus for adjustable droplet physical parameters and surface characteristics provided in this application embodiment, a rotary telescopic shaft coaxially mounted below the syringe can extend and retract along the axial direction of the syringe while rotating circumferentially. Simultaneously, evenly distributed along the circumference of the rotary telescopic shaft are... A hollow syringe, Each hollow syringe contains a corresponding [equipment / device / etc.] The device has several different sizes of dripping needles, and the different sizes of dripping needles can be adjusted to face the syringe outlet by rotating the telescopic shaft in the circumferential direction. The telescopic shaft can also be extended and retracted in the axial direction to make the dripping needle facing the syringe outlet engage or disengage from the syringe outlet.

[0024] By utilizing the rotating telescopic shaft to rotate circumferentially while simultaneously extending and retracting axially, the hollow syringe rotates and extends synchronously, allowing different sizes of dripping needles to be matched with the syringe outlet. In dripping experiments with different droplet sizes, the specifications of the dripping needles are adaptively adjusted, effectively avoiding manual replacement of the dripping needles. This allows different sizes of dripping needles to be connected to the syringe, enabling control of different droplet sizes. It effectively ensures that the droplet positions of different sizes of droplets are the same before and after replacing different sizes of needles, greatly improving the accuracy of droplet impact experiment results. Attached Figure Description

[0025] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. Wherein:

[0026] Figure 1 This is a schematic diagram of the structure of an impact test apparatus with adjustable droplet physical parameters and surface characteristics according to some embodiments of this application;

[0027] Figure 2 for Figure 1A cross-sectional view of the impact experimental apparatus with adjustable droplet physical parameters and surface characteristics.

[0028] Figure 3 This is a schematic diagram of the assembly of a rotary telescopic shaft and a hollow syringe according to some embodiments of this application;

[0029] Figure 4 This is a schematic diagram of the assembly of a rotary telescopic shaft and a drive motor according to some embodiments of this application;

[0030] Figure 5 This is a schematic diagram of the structure of a drive connecting cylinder according to some embodiments of this application;

[0031] Figure 6 This is a schematic diagram of the structure of a cavity syringe provided according to some embodiments of this application;

[0032] Figure 7 This is a schematic diagram of the structure of a dripping needle and a hollow syringe according to some embodiments of this application;

[0033] Figure 8 This is a schematic diagram of the assembly of a dripping needle according to some embodiments of this application;

[0034] Figure 9 This is a schematic diagram of the structure of an impact test system with adjustable droplet physical parameters and surface characteristics according to some embodiments of this application.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1. Syringe; 2. Rotary telescopic shaft; 3. Hollow syringe; 4. Dropping needle; 5. Drive connecting tube; 6. Drive motor; 7. Thermocouple; 8. Heating unit; 9. Cooling unit; 31. Centering and positioning mounting groove; 41. Positioning and mounting end; 42. Dropping tube; 43. Centering and positioning mounting slide rail; 51. Drive cam groove. Detailed Implementation

[0037] The present application will now be described in detail with reference to the accompanying drawings and embodiments. Various examples are provided by way of explanation and not by way of limitation. In fact, those skilled in the art will understand that modifications and variations can be made to the present application without departing from the scope or spirit of the present application. For example, a feature shown or described as part of one embodiment may be used in another embodiment to produce yet another embodiment. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention should fall within the scope of protection of the embodiments of the present invention.

[0038] Currently, in droplet impact experiments, when different droplet sizes need to be dropped, the experimenter usually manually changes needles of different specifications to achieve the dropping operation. In order to effectively ensure that the droplet drop position is consistent before and after changing the needle size, the experimenter needs to repeatedly adjust the experimental platform. During this process, relying solely on the experimenter's visual observation of the needle position, experimental platform position, and droplet drop position to roughly determine that the droplet drop position is the same before and after changing the needle size cannot guarantee the experimental accuracy and brings great uncertainty to the droplet impact experiment results.

[0039] Based on this, this embodiment proposes an impact experimental device for adjustable droplet physical parameters and surface characteristics. By cooperating with a syringe containing needles of different specifications, the movement of the syringe is adaptively adjusted to connect the needles of different specifications with the syringe, thereby achieving control of droplets of different sizes. At the same time, during the adaptive adjustment process, the position of the syringe, the position of the experimental platform, and the drop line remain unchanged before and after the replacement of different needle specifications. This ensures that the droplet drop position is precisely constant before and after the replacement of different needle specifications, thus fully guaranteeing the experimental precision and the accuracy of the experimental results.

[0040] like Figures 1 to 7 As shown, the adjustable droplet physical parameters and surface characteristics impact experimental device includes: a syringe 1, a rotary telescopic shaft 2, and a hollow syringe 3; wherein, the rotary telescopic shaft 2 is coaxially mounted below the outer bottom surface of the syringe barrel of the syringe 1, and the rotary telescopic shaft 2 can extend and retract along the axial direction of the syringe barrel while rotating in the circumferential direction. ( (A positive integer) hollow syringes 3 are evenly distributed around the outside of the rotating telescopic shaft 2 along its circumference, and ( (A positive integer) 3 hollow syringes are installed corresponding to each 4 different sizes of dripping needles.

[0041] The rotating telescopic shaft 2 moves axially and rotates circumferentially, driving the hollow syringe 3 to move axially and rotate circumferentially at the same time. The circumferential rotation causes the dripping needles 4 of different specifications installed in the hollow syringe 3 to be aligned with the liquid outlet on the syringe. The axial telescopic movement enables the dripping needles 4 to engage or disengage with the liquid outlet on the syringe.

[0042] Therefore, by means of the simultaneous circumferential rotation and axial extension and retraction of the rotating telescopic shaft 2, the hollow syringe 3 is driven to rotate and extend and retract synchronously, so that the dripping needles 4 of different specifications can be matched with the liquid outlet of the syringe. Furthermore, in dripping experiments of different droplet sizes, the specifications of the dripping needles 4 are adaptively adjusted, effectively avoiding manual replacement of the dripping needles 4, and connecting the dripping needles 4 of different specifications with the syringe 1 to achieve dripping control of different droplet sizes. This effectively ensures that the dripping position of different droplet sizes remains unchanged before and after the replacement of the dripping needles 4, greatly improving the accuracy of the droplet impact experiment results.

[0043] In a specific example, the syringe 1 has a stainless steel syringe barrel, inside which a temperature control module and a thermocouple array are installed. Specifically, the temperature control module, installed inside the syringe barrel, is used to regulate the temperature of the injected solution in real time. The thermocouple array includes multiple thermocouples 7, evenly distributed on the bottom plate of the syringe barrel, for real-time monitoring of the temperature of the injected solution. Furthermore, the temperature control module and thermocouple array are connected to an external temperature controller and paperless recorder via power signal lines to collect the temperature of the injected solution in real time.

[0044] The temperature control module includes a heating unit 8 and a cooling unit 9, which adjust the temperature of the injection solution in the syringe in real time through electric heating or cooling. The heating unit 8 is installed on the bottom plate of the syringe, using an electric heating rod that penetrates the bottom plate. The cooling unit 9 can be a tubular cooler or a heat pipe cooler, embedded in the inner wall or bottom plate of the syringe. For example, a recessed mounting hole is provided on the bottom plate of the syringe 1, and the cooling pipe of the tubular cooler or heat pipe cooler is embedded in the mounting hole.

[0045] In this embodiment, the rotary telescopic shaft 2 is arranged on the outer surface of the syringe barrel of the syringe 1 via the drive connecting cylinder 5. The inner sidewall of the drive connecting cylinder 5 is provided with a drive cam groove 51 along the circumferential direction. Correspondingly, the upper end of the rotary telescopic shaft 2 is symmetrically arranged with a drive motor 6 along the radial direction. The output end of the drive motor 6 is provided with a drive wheel. The drive wheel moves according to the cam curve of the drive cam groove 51. The drive wheel and the drive cam groove 51 are driven by friction or gear meshing, which drives the rotary telescopic shaft 2 to rotate circumferentially and move axially.

[0046] The rotary telescopic shaft 2, symmetrically arranged radially at its upper end and located within the drive cam groove 51, supports the rotary telescopic shaft 2, the hollow syringe 3, and the dripping needle 4 installed within the hollow syringe 3, suspending them on the drive connecting cylinder 5. Simultaneously, the drive motor 6 drives the drive wheels and the drive cam groove 51 through friction transmission or gear meshing, causing the rotary telescopic shaft 2 to rotate circumferentially while simultaneously extending and retracting axially. Here, according to the formula:

[0047]

[0048] Determine the cam curve of the drive cam groove 51; where, The trajectory of the drive wheel within the drive cam groove 51. The height travel of the dripping needle 4 as it extends and retracts axially along the rotating telescopic shaft 2; The rotation angle of the telescopic shaft 2 along the circumferential direction. ; The total number of hollow syringes 3 evenly distributed circumferentially along the rotational telescopic axis 2 and It is an even number.

[0049] In a specific example, when friction transmission is used between the drive wheel and the drive cam groove 51, multiple support components are also evenly distributed circumferentially between the two drive motors 6. Each support component is provided with a support rod extending radially. One end of the support tube is connected to the rotary telescopic shaft 2, and the other end is rotatably mounted with a support wheel. The support wheel is located in the drive cam groove 51, thereby achieving auxiliary support and limiting of the rotary telescopic shaft 2.

[0050] In another specific example, friction transmission is used between the drive wheel and the drive cam groove 51. An auxiliary limiting groove matching the support wheel is also provided on the inner wall of the drive connecting cylinder 5. The auxiliary limiting groove is set parallel to the drive cam groove 51, uses the same cam curve, and is located above or below the drive cam groove 51.

[0051] In this embodiment, the rotating telescopic shaft 2 is coaxially arranged with the syringe. Hollow syringes 3 are evenly distributed around the circumference of the rotating telescopic shaft 2. Each hollow syringe 3 is connected to the rotating telescopic shaft 2 by multiple connecting rods arranged in parallel along the axial direction of the rotating telescopic shaft 2 and extending radially, so as to effectively ensure that the hollow syringes 3 are parallel to the rotating telescopic shaft 2, thereby ensuring the accuracy of the dripping experiment.

[0052] Each hollow syringe 3 has a flared opening at its upper end, wider at the top and narrower at the bottom. A centering and positioning mounting groove 31 is provided along the generatrix of the inner wall of the flared opening, and multiple such grooves are evenly distributed circumferentially. Correspondingly, the upper end of the dripping needle 4 has an inverted conical structure matching the flared opening, and multiple centering and positioning mounting rails 43 matching the centering point grooves are evenly distributed circumferentially on the outer wall of the inverted conical structure. Thus, through the cooperation of the centering and positioning mounting grooves 31 and the centering point mounting rails, and the flared opening and inverted conical structures, the dripping needle 4 is effectively ensured to be coaxially mounted inside the hollow syringe 3, thereby aligning the dripping needle 4 with the liquid outlet of the syringe and improving the experimental accuracy of the dripping experiment.

[0053] In a specific example, both the centering positioning mounting groove 31 and the centering positioning mounting slide rail 43 are dovetail-shaped. By matching the dovetail-shaped cross-sections of the centering positioning mounting groove 31 and the centering point mounting slide rail, the coaxiality of the dripping needle 4 and the cavity syringe 3 is further improved. On the other hand, the dripping needle 4 is limited relative to the cavity syringe 3. The inclined surface of the dovetail-shaped cross-section avoids the possible tilting deviation of the dripping needle 4 relative to the cavity syringe 3. At the same time, the circumferential displacement of the dripping needle 4 relative to the cavity syringe 3 is limited to avoid the rotational deviation of the dripping needle 4 relative to the cavity syringe 3.

[0054] In another specific example, the dripping needle 4 includes: a positioning and mounting end 41 and a dripping tube 42. The positioning and mounting end 41 is an inverted conical structure that matches the flared mouth structure, and its outer wall has multiple centering point mounting rails evenly distributed circumferentially along the centering point mounting groove. The dripping tube 42 is detachably mounted on the lower end of the positioning and mounting end 41. Both the positioning and mounting end 41 and the dripping tube 42 are provided with dripping needle holes that are coaxial with the inverted conical structure and pass through it axially.

[0055] By detachably connecting the drip tube 42 to the positioning and mounting end 41, drip tubes 42 of different specifications can be connected to the positioning and mounting end 41 to form drip needles 4 of different sizes. In other words, the positioning and mounting end 41 and the hollow syringe 3 are standardized. Drip needles 4 of different specifications have the same positioning and mounting end 41 and are installed in the same hollow syringe 3. The only difference is the specification of the drip tube 42, which effectively improves the standardization and modularity of the drip needles 4.

[0056] In this embodiment, the rotating telescopic shaft 2 rotates circumferentially while extending and retracting axially, driving the hollow syringe 3 to rotate and extend synchronously. This allows different sizes of dripping needles 4 to be matched with the liquid outlet of the syringe 1. In dripping experiments with different droplet sizes, the specifications of the dripping needles 4 are adaptively adjusted, effectively avoiding manual replacement of the dripping needles 4. This allows different sizes of dripping needles 4 to be connected to the syringe 1, enabling control of different droplet sizes. This effectively ensures that the droplet positions of different sizes of droplets are the same before and after replacing different sizes of needles, greatly improving the accuracy of droplet impact experiment results.

[0057] This embodiment also provides an impact test system with adjustable droplet physical parameters and surface characteristics. The system employs the impact test apparatus with adjustable droplet physical parameters and surface characteristics described in any of the above embodiments. The impact test apparatus is mounted on a fixed cross rail to adjust its height and horizontal position relative to the surface of the adjustable test platform. The impact test system further includes: a temperature unit, located on the adjustable test platform, for real-time monitoring and control of the platform's temperature; and a light control and imaging unit, including at least a camera and a spotlight located at the same horizontal height on both sides of the adjustable test platform, for real-time imaging of the droplet falling.

[0058] In this embodiment, the impact experimental device is fixed to a cross slide rail via a sliding table. The position of the impact experimental device is adjusted via the cross slide rail to precisely control the droplet's falling height and landing position. The high-speed camera, adjustable experimental platform, and spotlight are at the same horizontal level. The spotlight's light source is transmitted to the high-speed camera lens through the experimental droplet. The droplet blocks part of the light source, while the remaining light is transmitted to the high-speed camera. Consequently, the high-speed camera images a picture composed of a white background and black droplets, making the droplets themselves and their edge contours more clearly visible, thus improving the accuracy and reliability of the experiment.

[0059] 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 are not intended to 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.

[0060] 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.

[0061] 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, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0062] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0063] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0064] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An impact experimental apparatus with adjustable droplet physical parameters and surface characteristics, characterized in that, include: syringe; A rotary telescopic shaft is coaxially mounted with the syringe and located below the syringe. It can extend and retract axially while rotating circumferentially. The rotary telescopic shaft is arranged on the outer bottom surface of the syringe through a drive connecting cylinder. The inner sidewall of the drive connecting cylinder is provided with a drive cam groove along the circumferential direction. Correspondingly, a drive motor is arranged radially symmetrically at the upper end of the rotary telescopic shaft. The output end of the drive motor is provided with a drive wheel. The drive wheel moves along the cam curve of the drive cam groove, driving the rotary telescopic shaft to rotate circumferentially while extending and retracting axially. The hollow syringe is connected to a rotating telescopic shaft by multiple connecting rods arranged side-by-side along the axial direction and extending radially, and the connecting rods are evenly distributed circumferentially along the rotating telescopic shaft. Install one by one. Different sizes of dripping needles are used to adjust the position of the dripping needles relative to the syringe outlet by rotating the telescopic shaft circumferentially, and to engage or disengage the dripping needles relative to the syringe outlet by extending and retracting the telescopic shaft axially. It is a positive integer; The upper opening of the hollow syringe is a flared structure with a larger upper opening and a smaller lower opening. A centering and positioning mounting groove is provided on the inner side wall of the flared structure along the generatrix direction, and multiple centering and positioning mounting grooves are evenly distributed around the circumference. Correspondingly, the upper end of the dripping needle is provided with an inverted conical structure that matches the flared structure, and multiple centering and positioning mounting slides that match the centering and positioning mounting grooves are evenly distributed around the outer side wall of the inverted conical structure. And according to the formula: Determine the cam curve of the driving cam groove; where, The trajectory of the drive wheel within the drive cam groove. The height travel of the dripping needle as it extends and retracts axially along the rotating telescopic shaft; The rotation angle of the telescopic shaft along the circumferential direction. ; The total number of hollow syringes evenly distributed circumferentially along the axis of rotation and telescopic movement. It is an even number.

2. The apparatus according to claim 1, characterized in that, The drive wheel is driven by friction with the groove of the drive cam or by gear meshing.

3. The apparatus according to claim 1, characterized in that, Both the centering and positioning mounting groove and the centering and positioning mounting slide rail have dovetail-shaped cross sections.

4. The apparatus according to claim 1, characterized in that, The dripping needle includes: a positioning and mounting end and a dripping tube. The positioning and mounting end is an inverted conical structure that matches the flared mouth structure, and multiple centering and positioning mounting slides that match the centering and positioning mounting groove are evenly distributed along the outer side wall in the circumferential direction. The drip tube can be detachably installed at the lower end of the positioning and installation head; Both the positioning and installation end and the drip tube are equipped with drip needle holes that are coaxial with the inverted conical structure and pass through it axially.

5. The apparatus according to claim 1, characterized in that, Multiple thermocouples are evenly distributed at the bottom of the syringe's injection chamber to monitor the liquid temperature inside the injection chamber in real time.

6. An impact experimental system with adjustable droplet physical parameters and surface characteristics, characterized in that, The impact testing apparatus, comprising the adjustable droplet physical properties and surface characteristics as described in any one of claims 1-5, is mounted on a fixed cross slide rail for adjusting its height and horizontal position relative to the surface of the adjustable testing platform; the impact testing system further comprises: The temperature unit is installed on the adjustable experimental platform and is used to monitor and control the temperature of the adjustable experimental platform in real time. The light control and imaging unit includes at least a camera and a spotlight located at the same horizontal height on both sides of the adjustable experimental platform, for capturing images of the droplets falling in real time.

Images