Device and method for testing icing adhesive force of liquid drops at different impact speeds

Abstract

The invention discloses a device for testing icing adhesive force of liquid drops at different impact speeds. The device comprises a water dripping system, a telescopic guide pipe, a guide rail bottom plate assembly and a bottom plate angle adjusting mechanism. The dripping system is located at the top of the device and provided with a dripping device, and single or continuous liquid drops can be generated. And the telescopic guide pipe can adjust the drop height of the liquid drop, so that the impact speed of the liquid drop is controlled, and the icing experiment requirements under various working conditions are met. A slidable guide rail is arranged in the guide rail bottom plate assembly, samples made of various materials such as copper, aluminum and steel can be installed and taken out, a detachable ice mold device is arranged on a sample plate, the bottom plate angle adjusting mechanism is composed of two precise elevators at the bottom and a lateral rotating shaft, and the inclination angle of a bottom plate can be adjusted by controlling different heights of the elevators. Therefore, the icing process that liquid drops impact the surface of a material at different angles can be simulated.

Description

Technical Field

[0001] The present invention relates to the technical field of icing test of materials in low-temperature environments, and in particular to a device and method for testing the icing adhesion of droplets at different impact velocities. Background Art

[0002] In fields such as aerospace, shipping, wind power generation, high-voltage transmission lines, and cold-zone transportation, structural surfaces often experience icing in low-temperature environments. Icing not only degrades the functional properties of the material surface but can also lead to reduced lift, increased aerodynamic drag, load fluctuations, and interference with communication signals. In severe cases, it can even compromise operational stability and public safety.

[0003] The study found that the adhesion strength of ice is affected by a variety of factors, including the initial impact velocity of the droplet, the impact angle, the microstructural characteristics of the material surface, the difference in hydrophilicity, the temperature distribution and other parameters. Among them, the impact velocity of the droplet is the key variable that determines its kinetic energy release and spreading behavior, which is directly related to the formation of ice morphology and the change in adhesion strength. According to the first issue of "Ice and Snow Science and Engineering" in 2022, under -10°C conditions, droplets hit metal specimens at speeds of 1.0m / s, 2.0m / s and 3.0m / s respectively. The initial adhesion force of the resulting ice layer increased from 120kPa to more than 360kPa, accompanied by an increase in the coverage area and thickness of the ice layer. This result shows that when simulating actual high-speed wind and rain, hail impact and other working conditions, the droplet velocity must be strictly controlled and adjusted.

[0004] Currently, common ice adhesion test methods include shear loading method, pull-off method, heavy hammer impact method and centrifugal stripping method. These methods mostly use static ice samples as test objects, and cannot accurately reflect the dynamic freezing behavior during the droplet impact process; at the same time, the tests mostly use fixed loading structures, which makes it difficult to simulate the natural conditions of free fall or oblique angle impact. In addition, existing test devices are often complex in structure and have a single adjustment function. They cannot achieve impact speed control, impact angle adjustment, droplet size change and rapid replacement of multiple samples on the same platform, resulting in insufficient ability to reproduce experimental scenarios, low data repeatability and poor scalability.

[0005] While some research institutions have attempted to construct droplet generation systems by combining an electric platform with syringe dripping to simplify testing processes and improve accuracy, these devices still lack precision in speed control, flexibility in drop height adjustment, and space utilization. The difficulty in linearly controlling the impact velocity from the drop height, the redundant platform structure, and the limited drop velocity range make it difficult to meet the demands of specialized operating conditions such as high impact energies and non-perpendicular angles. Summary of the Invention

[0006] Purpose of the invention: The present invention proposes a device and method for testing the freezing adhesion of droplets at different impact velocities. By controlling the different heights of the elevator, the inclination angle of the base plate can be adjusted to simulate the freezing process of droplets impacting the material surface at different angles.

[0007] Technical solution: The present invention proposes an ice adhesion test device for droplets with different impact velocities, comprising a base plate angle adjustment mechanism, a guide rail base plate assembly located above the base plate angle adjustment mechanism, a telescopic catheter assembly fixed on the base plate angle adjustment mechanism, and a dripping system connected to the telescopic catheter assembly; the dripping system comprises a dripping pipe and a micro pump located inside the dripping pipe, the dripping pipe comprises a dripping pipe and an input end; the telescopic catheter assembly is axially telescopic to adjust the height, and the input end of the dripping pipe is connected to the top of the telescopic catheter assembly; the guide rail base plate assembly comprises a sample plate, an ice-forming mold fixed on the sample plate, a guide rail and a slider; the base plate angle adjustment mechanism comprises an ice-forming chamber, an elevator located below the ice-forming chamber and a horizontal rotating shaft, the slider is provided on the upper surface of the ice-forming chamber, the slider cooperates with the guide rail below the sample plate, the guide rail base plate assembly is located inside the ice-forming chamber, the horizontal rotating shaft is provided at both ends of one side of the ice-forming chamber, and an elevator is provided at both ends of the other side, and the lower end of the outer tube is fixed to the outside of the ice-forming chamber.

[0008] Preferably, the inner diameter of the dropper is 1.2 mm, so as to generate droplets with a diameter of 2.5 mm.

[0009] Preferably, the input end of the drip pipe is covered with a constant temperature heating sleeve.

[0010] Preferably, the telescopic catheter assembly includes an inner tube, a middle tube located outside the inner tube, and an outer tube located outside the middle tube. The inner tube and the middle tube and the middle tube and the outer tube can be telescopically slid along the axial direction and locked by a spiral locking structure. The inner tube, the middle tube and the outer tube are made of aluminum alloy, and the inner wall is covered with a polytetrafluoroethylene ice-phobic anti-stick coating. The outer walls of the inner tube, the middle tube and the outer tube are provided with height scales. The inner tube is shaped as an "L"-shaped catheter, and the output end of the dropper is connected to the lateral end of the inner tube.

[0011] Preferably, a locking structure is provided on the top of the slider.

[0012] Preferably, the ice-forming mold is a cylindrical structure with upper and lower openings, the side wall material is polytetrafluoroethylene, and the bottom edge of the ice-forming mold is provided with a 5mm silicone base.

[0013] Preferably, the elevator is provided with an elevator knob.

[0014] A method for testing the ice adhesion of droplets at different impact velocities comprises the following steps:

[0015] Step 1: Debug the dripping system: Pour the liquid medium required for the experiment into the liquid supply container of the dripping system to ensure that the liquid level is sufficient and there are no bubbles in the pipeline. Start the micro pump in the dripping system for a trial run and observe whether there are stable droplets forming and falling at the outlet of the dripping pipe. By adjusting the output flow rate or frequency of the micro pump, set the required dripping speed and single drop volume to obtain the droplet formation frequency required for the experiment. Then turn on the constant temperature heating sleeve covering the outside of the dripping pipe and set the corresponding temperature value. After completing the above debugging, the dripping system enters the standby state;

[0016] Step 2: Adjust the height of the telescopic tube assembly: Adjust the drop height of the telescopic tube assembly according to the droplet impact velocity required for the test;

[0017] Step 3: Sample Installation and Replacement: Select the sample plate to be tested and install it on the freezing chamber, with the sample plate surface facing upward and its center aligned vertically below the drip pipe. Secure the sample plate firmly to the sliding mounting block, slide the slider along the guide rail to reposition the sample plate to the designated position inside the freezing chamber, and attach the ice-forming mold to the sample plate. Close the freezing chamber door.

[0018] Step 4: Bottom plate angle adjustment: According to the test requirements, adjust the bottom plate angle adjustment mechanism to adjust the tilt angle of the sample plate;

[0019] Step 5: Dripping Ice Test: Confirm that the ambient temperature in the ice chamber has reached the low temperature conditions required for the test, then start the micro pump according to the set parameters. Droplets will drip from the drip pipe from the set height and hit the surface of the sample plate at a predetermined speed, causing the droplets to freeze in the ice-forming mold. When the ice on the sample plate reaches the expected thickness or ice shape, stop the micro pump supply, close the dripping system, and end the dripping process;

[0020] Step 6: Adhesion test and parameter change: After the dripping stops, open the door of the ice chamber and take out the frozen sample plate and ice mold; after the ice body is frozen in the ice mold and formed, use shearing or pulling to peel off the ice column, and use the force sensor to record the maximum force value F required for peeling adh According to the definition of ice adhesion, the adhesion strength per unit area is calculated using the following formula:

[0021]

[0022] Among them: F adh is the adhesion force per unit area of ice; F total is the total force required to peel off the ice; A is the contact area between the ice and the sample.

[0023] Preferably, in step four, the angle is adjusted back to horizontal or to other angles, and the front and rear end heights are adjusted by rotating the elevator knob of the elevator until the corresponding target angle value is reached; the bottom plate angle adjustment mechanism can realize the setting of any angle of the sample plate from horizontal to the predetermined maximum inclination range.

[0024] Preferably, the dripping freezing experiment in step 5 includes a single drop impact freezing test or a continuous dripping freezing test.

[0025] Beneficial effects: The present invention proposes a device and method for testing the ice adhesion of droplets at different impact velocities, and the beneficial effects include: (1) Through the three-section adjustable telescopic catheter structure, the droplet falling height can be continuously adjusted within a certain range, thereby realizing the control of the impact velocity, which is applicable to a variety of experimental conditions. (2) The bottom plate angle adjustment mechanism adopts two sets of lifting mechanisms in conjunction with a transverse rotating shaft, which has a stable structure and a wide angle adjustment range, and can achieve precise setting of the platform elevation angle, thereby improving the flexibility of the impact angle simulation. (3) The sample installation structure adopts a sliding slider and a clamping position, which is easy to install and fast to sample. It supports the replacement of samples of various materials such as copper, aluminum, and stainless steel, and effectively improves the experimental efficiency. (4) The dripping system integrates a micro pump control device and is equipped with an external heating constant temperature sleeve to effectively ensure the continuity of the droplets and the smoothness of the nozzle outlet. The dripping pipe adopts a controllable dropper with an inner diameter of 1.2 mm, which can stably generate droplets with a diameter of about 2.5 mm, and is suitable for long-term operation in low temperature environments. (5) The ice chamber adopts an insulated box structure, and its bottom connection pad is equipped with a rubber gasket, which can not only improve the thermal insulation effect, but also reduce the vibration impact of the lifting mechanism movement on the platform structure, thereby ensuring the accuracy of the experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the overall structure of the first embodiment of the ice adhesion test device for droplets with different impact velocities in the present invention;

[0027] Figure 2 This is an enlarged structural diagram of the dripping system in the first embodiment of the ice adhesion test device for droplets at different impact velocities of the present invention;

[0028] Figure 3 2 is a cross-sectional view of the structure of the dripping system of the first embodiment of the ice adhesion test device at different impact speeds of the present invention;

[0029] Figure 4 A three-dimensional structural diagram of the telescopic catheter assembly of the first embodiment of the ice adhesion test device for droplets at different impact velocities in the present invention

[0030] Figure 5 3D diagram of the guide rail base plate assembly in the first embodiment of the ice adhesion test device for droplets at different impact velocities according to the present invention;

[0031] Figure 6 This is a structural diagram of the bottom plate angle adjustment mechanism in the first embodiment of the ice adhesion test device for droplets with different impact velocities in the present invention. DETAILED DESCRIPTION

[0032] like Figure 1 As shown, the ice adhesion test device for droplets with different impact velocities in the present invention is generally configured as a modular structure, mainly comprising a dripping system 1, a telescopic guide tube assembly 2, a guide rail base assembly 3, and a base angle adjustment mechanism 4. Figure 2 and Figure 3 As shown, the dripping system 1 is arranged at the top of the overall structure of the device. The dripping system 1 mainly consists of a dripping pipe 11 and a micro pump 13. The dripping pipe 11 includes a dripping pipe 111 and an input end 112. The input end 112 is connected to the telescopic catheter assembly 2 below to form a passage. The input end 112 of the dripping pipe 11 is covered with a constant temperature heating sleeve 12 to ensure that the droplets do not freeze prematurely in the low-temperature experimental environment. The micro pump 13 is located inside the input end 112. The micro pump 13 helps to quickly establish the conditions for droplet generation in the early stages of the experiment, ensuring uniform droplet size and stable frequency. The telescopic catheter assembly 2 adopts a three-section nested structure to facilitate height adjustment. The three sections of the catheter are an outer tube 21, a middle tube 22, and an inner tube 23. The dripping pipe 11 is installed as a whole on the horizontal water outlet section at the top of the inner tube 23.

[0033] like Figure 4 As shown, the lower telescopic catheter assembly 2 is made of high-strength aluminum alloy, with a polytetrafluoroethylene (PTFE) ice-repellent coating sprayed on the inner wall to reduce ice buildup. An annular locking structure 24 is installed between the outer tube 21 and the middle tube 22, and between the middle tube 22 and the inner tube 23. Rotating the screw ring allows for quick locking and unlocking of different sections. Limit marks 25 are marked on the outer wall of the catheter for easy viewing and height adjustment. The main function of the telescopic catheter assembly 2 is to control the droplet's falling height, thereby adjusting the impact velocity.

[0034] The guide rail base plate assembly 3 is arranged at the bottom of the device, such as Figure 5 As shown, the guide rail base plate assembly 3 includes two parallel guide rails 31, a sliding block 32, and a sample plate 35. The guide rails 31 are welded to the inner surface of the ice chamber 43. The sliding block 32 is fixed below the metal sample plate and can slide freely along the guide rail 31. A removable sample retaining structure is provided on the upper portion of the sliding block 32 for quickly installing a variety of sample plates 35, such as aluminum alloy, stainless steel, and copper plates. The sample retaining structure adopts a double-sided clamping mechanism and cooperates with positioning pin holes to ensure the stability of the sample during the test. The sample plate 35 is provided with an ice-forming mold 33. The ice-forming mold 33 is a cylindrical structure with upper and lower openings. The bottom of the cavity is the sample plate 35. The sidewalls of the ice-forming mold 33 are made of polytetrafluoroethylene, and the bottom edge of the ice-forming mold 33 is provided with a 5mm silicone base 34 to prevent ice from forming on the walls.

[0035] The bottom plate angle adjustment mechanism 4 is located below the guide rail bottom plate assembly 3 and includes two elevators 41, a horizontal rotating shaft 42 and an ice chamber. The elevators 41 are installed at both ends of one side below the ice chamber 43. By controlling the lifting height difference, there is an angle scale on the elevator 41; the fine adjustment of the bottom plate elevation angle is achieved, which facilitates the operator to accurately control the impact angle.

[0036] like Figure 1 As shown, the entire guide rail base plate assembly 3 is installed on the upper surface of the icing chamber, and the icing chamber 43 is set on the upper bearing platform of the base plate angle adjustment mechanism 4 and fixed by welding.

[0037] In addition to the aforementioned embodiments, the present invention also incorporates an annular locking structure 24. Precision threads are incorporated into the inner lumen of the catheter, matching the corresponding spiral patterns on the outer wall. The catheter's length can be adjusted by rotation, enhancing the stability and precision of the telescopic catheter. To enhance the stability and water-tightness of the connection between the drip system and the catheter, a threaded straight-through connector is employed. One end of the connector's external threads screw into the inner threads of the catheter, while the other end connects to the drip system's outlet. The connector is made of polytetrafluoroethylene, which is corrosion-resistant and low-temperature-resistant.

[0038] Figure 6 The structure of the bottom plate angle adjustment mechanism 4 is further demonstrated. The electric lifting mechanism 4 is placed between the support base and the load-bearing platform. A screw-nut drive structure is adopted internally, and combined with precision guide rail guidance, stable translation of the lifting platform can be achieved.

[0039] In summary, through the design and combination of the above structures, the ice adhesion test device for droplets with different impact velocities of the present invention can realize droplet velocity adjustment, angle change control, multiple sample installation and freezing process simulation, providing a stable and reliable experimental platform for subsequent ice layer adhesion strength measurement and anti-icing performance evaluation.

[0040] During the actual laying stage, the specific construction steps are as follows:

[0041] Step one, debugging of the dripping system: inject water or other liquid medium required for the experiment into the liquid supply container of the dripping system 1, and ensure that the liquid level is sufficient and there are no bubbles in the pipeline. Start the micro pump 13 in the dripping system 1 for trial operation, and observe whether there are droplets stably formed and falling at the outlet of the dripping pipe 11. By adjusting the output flow or frequency of the micro pump 13, the required dripping speed and single drop volume are set to obtain the ideal droplet formation frequency. At the same time, turn on the constant temperature heating sleeve 12 coated on the outside of the dripping pipe 11, and set the temperature to an appropriate range, so as to prevent the dripping pipe 11 outlet from freezing and clogging due to the low temperature of the environment, and ensure that the droplets can be continuously and smoothly generated and dripped. After completing the above debugging, the dripping system 1 enters standby mode, ready to start the formal dripping freezing experiment.

[0042] Step 2, adjust the height of the telescopic catheter: adjust the falling height of the telescopic catheter assembly 2 according to the droplet impact speed required for the test. Loosen the annular locking structure 24 between the outer tube 21 and the inner tube 23 of the telescopic catheter to allow the inner tube to slide freely axially inside the outer tube 21. Then, refer to the height scale 25 on the outer wall of the catheter to adjust the telescopic catheter assembly 2 to the required target height position. After the height is adjusted to the right position, tighten the locking structure 24 to fix the catheter length to prevent the catheter from sliding and deviating during the test. At this point, the falling height of the droplets dripping from the dripping system 1 has been set, and the corresponding droplet impact speed has also been determined.

[0043] Step 3, sample installation and replacement: Select the sample plate 35 to be tested and install it on the guide rail base plate assembly 3. The sample material can be different materials such as copper, aluminum, stainless steel, etc. to meet the test requirements of different working conditions. When installing or replacing the sample, first open the side door of the ice chamber 43 to expose the sample sliding installation structure 42 on the guide rail base plate assembly 3. Figure 3 As shown, two left and right guide rails 31 are arranged in parallel in the guide rail base plate assembly 3, and a sliding mounting block 32 is slidably connected to the guide rails. During operation, hold the sliding mounting block 32 and slowly pull it out of the ice chamber along the guide rail 31 to facilitate taking and placing the sample. Next, release the detachable sample clamping structure on the top of the sliding mounting block 32 and remove the sample plate 35 used in the last test. Then, place the new sample plate 35 in the positioning groove of the clamping structure, ensuring that the surface of the sample plate 35 is facing upward and its center is aligned with the position vertically below the drip pipe 11. After confirming that the sample plate 35 is placed correctly, re-lock the clamping structure to firmly fix the sample plate 35 on the sliding mounting block 32 to avoid loosening and displacement. After the sample plate 35 is mounted and secured, the sliding mounting block 32 is pushed back along the guide rail 31 to its original test position, allowing the sample plate 35 to be repositioned in the designated position within the freezing chamber 43, ensuring that it faces the intended impact area of the falling droplets. The mold 33 is then firmly attached to the sample plate 35. Finally, the door of the freezing chamber 4 is closed, ensuring a good seal, creating a constant low-temperature environment for the next freezing experiment.

[0044] Step 4: Adjust the bottom plate angle: According to the test requirements, adjust the bottom plate angle adjustment mechanism 4 to set the tilt angle of the sample plate 35, thereby simulating the working condition of droplets impacting the surface at different angles of incidence. First, check the angle scale 411 on the elevator knob to obtain the current tilt angle of the guide rail bottom plate assembly 3. If the angle is not the value required for the test, it needs to be adjusted. During adjustment, the precision elevator knobs 411 at the front and rear ends of the bottom plate angle adjustment mechanism 4 are rotated to achieve the lifting and lowering of one side of the platform. Since one side of the guide rail bottom plate assembly 3 is hinged to the base via a transverse shaft 42, and the other side is supported by a set of precision elevators 41 at the front and rear ends, synchronously adjusting the height of the front and rear end elevators 41 will cause the platform to tilt around the shaft 42. If the platform angle needs to be adjusted back to horizontal or adjusted to another angle, rotate the elevator knob 411 in the opposite direction or fine-tune the front and rear end heights separately until the scale shows the target angle value. Similarly, the bottom plate angle adjustment mechanism 4 can be used to set the sample plate 35 to any angle within the predetermined maximum tilt range from horizontal to the horizontal. After the angle adjustment is completed, the position of the sample plate 35 is rechecked to ensure that the droplet receiving area after tilting is still within the trajectory of the vertical droplet, so as to ensure that the droplet can accurately impact the upper surface of the sample plate 35.

[0045] Step 5: Water Droplet Icing Test: After completing the above settings, the experiment simulating droplet impact freezing can begin. First, confirm that the ambient temperature in the freezing chamber has reached the low temperature required for the test (for example, the chamber temperature has dropped below 0°C), then start the micropump 13 to activate the dripping system 1. According to the set parameters, droplets will drip from the dripping pipe 11 at a steady frequency, guided by the telescopic guide tube assembly 2 and falling from a set height. They will impact the surface of the sample plate 35 at a predetermined speed, causing them to freeze in the mold 33. For a single-drop impact freezing test, only a single droplet can be dripped; for a continuous drip freezing test, the droplets can be allowed to drip continuously for a period of time, accumulating to form a certain thickness of ice layer on the sample surface. Once the droplet contacts the sample plate 35 in the low-temperature environment, it immediately cools and solidifies in the mold, gradually forming an adherent ice layer on the plate surface. The entire freezing process can be monitored through the transparent observation window of the freezing chamber 43. When the ice on the sample plate 35 reaches the expected thickness or ice form, the liquid supply of the micro pump 13 is stopped, the dripping system 1 is closed, and the dripping process ends.

[0046] Step 5: Adhesion test and parameter change: After the dripping stops, open the hatch of the ice chamber 43, hold the sliding mounting block 32 again, and slowly pull it out of the chamber along the guide rail 31 together with the frozen sample plate 35 and mold 33. After the ice body is frozen in the mold 33 and formed, use shearing or pulling to peel off the ice column, and use the force sensor to record the maximum force value F required for peeling. adh According to the definition of ice adhesion, the adhesion strength per unit area can be calculated using the following formula:

[0047]

[0048] Among them: F adh is the adhesion force per unit area of ice (Pa); F total is the total force required to peel the ice (N); A is the contact area between the ice and the sample (m 2 ).

[0049] If it is necessary to conduct the ice adhesion test for the next set of working conditions, you can choose to remove the residual ice layer on the sample plate 35 and reuse the sample plate 35, or replace it with a new sample plate 35. Then, adjust the corresponding parameters according to the new test requirements: if the droplet impact speed is changed, reset the height of the telescopic guide tube 2; if the impact angle is changed, adjust the inclination of the bottom plate; if a sample of a different material is replaced, install the sample plate 35 of the corresponding material. After the adjustment is completed, conduct a new dripping ice test. By sequentially changing the combination of parameters such as the droplet falling height, the inclination of the sample plate 35 and the sample material, this device can simulate the droplet freezing process under various working conditions, and can quickly switch experimental conditions to carry out a series of tests, greatly improving the experimental efficiency. During each parameter adjustment and test process, the position of each component is indicated by a scale to ensure the repeatability of the test conditions and the comparability of the results under different working conditions.

Claims

1. A device for testing the ice adhesion of droplets at different impact velocities, characterized in that: The invention comprises a bottom plate angle adjustment mechanism (4), a guide rail bottom plate assembly (3) located above the bottom plate angle adjustment mechanism (4), a telescopic catheter assembly (2) fixed on the bottom plate angle adjustment mechanism (4), and a dripping system (1) connected to the telescopic catheter assembly (2); the dripping system (1) comprises a dripping pipe (11) and a micro pump (13) located inside the dripping pipe (11); the dripping pipe (11) comprises a dripping pipe (111) and an input end (112); the telescopic catheter assembly (2) is telescopically adjustable in height along the axial direction, and the input end (112) of the dripping pipe (11) is connected to the top end of the telescopic catheter assembly (2); the guide rail bottom plate assembly (3) comprises a sample plate ( 35), an ice-forming mold (33), a guide rail (31) and a slider (32) fixed on the sample plate (35); the bottom plate angle adjustment mechanism (4) includes an ice-forming chamber (43), an elevator (41) and a transverse rotating shaft (42) located below the ice-forming chamber (43); the slider (32) is provided on the upper surface of the ice-forming chamber (43); the slider (32) cooperates with the guide rail (31) below the sample plate (35); the guide rail bottom plate assembly (3) is located inside the ice-forming chamber (43); the transverse rotating shaft (42) is provided at both ends of one side of the ice-forming chamber, and the elevator (41) is provided at both ends of the other side; the lower end of the outer tube (21) is fixed to the outside of the ice-forming chamber (43).

2. The ice adhesion test device for droplets at different impact velocities according to claim 1, characterized in that: The dropper (111) has an inner diameter of 1.2 mm and is used to generate droplets with a diameter of 2.5 mm.

3. The ice adhesion test device for droplets at different impact velocities according to claim 2, characterized in that: The input end (112) of the dripping pipe (11) is covered with a constant temperature heating sleeve (12).

4. The ice adhesion test device for droplets at different impact velocities according to claim 1, characterized in that: The telescopic catheter assembly (2) comprises an inner tube (23), a middle tube (22) located outside the inner tube (23), and an outer tube (21) located outside the middle tube (22). The inner tube (23) and the middle tube (22) and the middle tube (22) and the outer tube (21) can be telescopically slidable along the axial direction and locked by a spiral locking structure (24). The inner tube (23), the middle tube (22), and the outer tube (21) are made of aluminum alloy, and the inner walls are covered with a polytetrafluoroethylene ice-phobic anti-stick coating. The outer walls of the inner tube (23), the middle tube (22), and the outer tube (21) are provided with height scales (25). The inner tube (23) is shaped as an "L"-shaped catheter. The output end of the dropper (11) is connected to the lateral end of the inner tube (23).

5. The ice adhesion test device for droplets at different impact velocities according to claim 1, characterized in that: A locking structure is provided on the top of the slider (32).

6. The ice adhesion test device for droplets at different impact velocities according to claim 1, characterized in that: The ice-forming mold (33) is a cylindrical structure with upper and lower openings, and the side wall material is polytetrafluoroethylene. The bottom edge of the ice-forming mold (33) is provided with a 5mm silicone base.

7. The ice adhesion test device for droplets at different impact velocities according to claim 1, characterized in that: The elevator (41) is provided with an elevator knob (411).

8. A method for testing ice adhesion of droplets at different impact velocities according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: Debugging the dripping system: inject the liquid medium required for the experiment into the liquid supply container of the dripping system (1) to ensure that the liquid level is sufficient and there are no bubbles in the pipeline, start the micro pump (13) in the dripping system (1) for trial operation, observe whether there are droplets stably formed and falling at the outlet of the dripping pipe (11), and set the required dripping speed and single drop volume by adjusting the output flow rate or frequency of the micro pump (13) to obtain the droplet formation frequency required for the experiment, then turn on the constant temperature heating sleeve (12) wrapped around the outside of the dripping pipe (11) and set the corresponding temperature value. After completing the above debugging, the dripping system (1) enters the standby state; Step 2: Adjusting the height of the telescopic catheter: adjusting the drop height of the telescopic catheter assembly (2) according to the droplet impact velocity required for the test; Step 3: Sample installation and replacement: Select the sample plate (35) to be tested and install it on the freezing chamber (43), so that the surface of the sample plate (35) faces upward and its center is aligned with the position vertically below the drip pipe (11), and the sample plate (35) is firmly fixed on the sliding mounting block (32). The slider (32) is slid along the guide rail (31) to re-place the sample plate (35) at the designated position inside the freezing chamber (43), and the ice-forming mold (33) is adsorbed on the sample plate (35); the door of the freezing chamber (4) is closed; Step 4: Bottom plate angle adjustment: According to the test requirements, adjust the bottom plate angle adjustment mechanism (4) to adjust the tilt angle of the sample plate (35); Step 5: dripping ice test: confirm that the ambient temperature in the ice chamber has reached the low temperature condition required for the test, then start the micro pump (13) according to the set parameters, and droplets will drip from the drip pipe (11) from the set height and hit the surface of the sample plate (35) at a predetermined speed, so that the droplets freeze in the ice forming mold (33). When the ice on the sample plate (35) reaches the expected thickness or ice shape, stop the micro pump (13) to supply liquid, close the dripping system (1), and end the dripping process; Step 6: Adhesion test and parameter change: After the dripping stops, open the door of the ice chamber (43) and take out the frozen sample plate (35) and the ice forming mold (33); after the ice body is frozen in the ice forming mold (33) and formed, use shearing or pulling to peel off the ice column, and record the maximum force value F required for peeling by the force sensor adh According to the definition of ice adhesion, the adhesion strength per unit area is calculated using the following formula: Among them: F adh is the adhesion force per unit area of ice; F total is the total force required to peel off the ice; A is the contact area between the ice and the sample.

9. The ice adhesion test method of droplets at different impact velocities according to claim 8, characterized in that: In the fourth step, the angle is adjusted back to horizontal or to another angle, and the front and rear end heights are adjusted by rotating the elevator knob (411) of the elevator (41) until the corresponding target angle value is reached; and the bottom plate angle adjustment mechanism (4) can realize the setting of the sample plate (35) from horizontal to any angle within the predetermined maximum inclination range.

10. The ice adhesion test method of droplets at different impact velocities according to claim 8, characterized in that: The dripping freezing test in step 5 includes a single drop impact freezing test or a continuous dripping freezing test.

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