Device and method for measuring ice adhesion strength of elastic coating under periodic external force

Abstract

The application discloses a device and method for measuring ice adhesion strength of elastic coating under periodic external force, which comprises a refrigeration module, an ice adhesion strength measuring module and a control system; in the refrigeration module, a cooling liquid channel is arranged in the test base and connected with a refrigeration unit, and temperature measuring points of the uniform temperature table are arranged at equal intervals in the vertical direction inside the uniform temperature table; the ice adhesion strength measuring module comprises an elastic coating arranged on the surface of the uniform temperature table and a mold placed on the surface of the elastic coating, the mold is connected with a remote tension meter through traction lines on both sides, and each remote tension meter is arranged on a moving platform; the control system controls the coordinated work of the modules, adjusts the refrigeration capacity to control the low-temperature test surface temperature, controls the size and frequency of the periodic force, collects and records data and calculates the ice adhesion strength. The application can realize the measurement of the ice adhesion strength of the elastic coating surface under different temperature conditions under the periodic external force and the influence mechanism research.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of ice adhesion force measurement, and particularly relates to a device and method for measuring ice adhesion strength of an elastic coating under periodic external force. BACKGROUND

[0002] Ice formation is a common natural phenomenon and is widespread in the engineering field, which brings inconvenience and harm, such as aircraft wing icing in the aviation field, wind turbine blade icing in the power field, and refrigeration equipment surface icing, etc. Since the ice formation process is accompanied by the occurrence of ice adhesion phenomenon, the material surface weight increases, or the material surface is blocked, the optical material refraction ability and light transmission are interfered, etc. Therefore, how to efficiently and quickly evaluate the ice adhesion strength of the material surface is the basis for evaluating and designing the deicing method.

[0003] Ice adhesion strength is an important reference quantity for characterizing the ice prevention characteristics of the material surface. The current ice adhesion measurement device is mostly a centrifugal rotation method or a normal ice pushing method.

[0004] The centrifugal rotation method is to make the ice column fly outwards by the centrifugal force generated by rapid rotation, hit the sensor on the cavity wall, and then calculate the ice adhesion strength. The normal ice pushing method is to use a force gauge probe to push the frozen ice column on the sample surface, and the data measured by the force gauge when the ice column is pushed away is the ice adhesion strength of the material surface. The technical characteristics of both methods are to monotonically increase the force borne by the ice column sample until the critical value at which the ice column is separated. However, the limitation is that it cannot simulate the periodic external force that may occur in practice. For example, in the process of wind turbine operation, the gravity and centrifugal force of the ice block combined into a periodic external force when the blade is downward, the gravity and centrifugal force are in the same direction, and when the blade is upward, the gravity and centrifugal force are in different directions, and the external force borne by the ice block changes periodically. When the power cable is iced in winter, the wind blowing through the iced cable forms a periodic excitation force. There is also a technology of making the object surface iced and separated by mechanical excitation force. All these require accurate data of the ice adhesion strength of the material under the periodic external force.

[0005] The existing fan deicing technology can be divided into active and passive types, and the coating deicing belongs to the passive deicing category. Among them, the bonding force between the high elastic body and the ice is the smallest, and has good ice prevention performance. Studies have shown that the ice adhesion strength can be reduced to 50kPa by using super-hydrophobic coating, to 16kPa by using lubricating coating, and to 0.2kPa by using elastic coating. Therefore, the hydrophobic elastic coating has become a new anti-icing coating material in recent years, which can effectively reduce the ice adhesion strength under the action of periodic external force by using the local stress generated by the uneven stiffness to reduce the adhesion between the ice layer and the coating.

[0006] Therefore, how to provide a kind of ice adhesion strength testing device and testing method capable of simulating periodic external force action, capable of accurately measuring the ice adhesion strength of elastic coating surface under periodic external force action, researching the change mechanism of ice adhesion strength of elastic coating, and good operability and repeatability are the problems that the skilled in the art urgently need to solve. SUMMARY

[0007] The application provides a kind of ice adhesion strength measuring device and method under periodic external force action of elastic coating, can realize the measurement and influence mechanism research of ice adhesion strength of elastic coating surface under periodic external force action at different temperature conditions, and can guarantee the accuracy of measurement result, with good operability and repeatability.

[0008] A kind of ice adhesion strength measuring device under periodic external force action of elastic coating, including refrigeration module, ice adhesion strength measuring module and control system;

[0009] The refrigeration module includes refrigeration unit, test base and isothermal platform;The isothermal platform is arranged on the test base, and the test base is provided with a cooling liquid channel, which is connected with the refrigeration unit, and the inlet and outlet of the cooling liquid channel are provided with liquid inlet temperature measuring point and liquid outlet temperature measuring point;Three isothermal platform temperature measuring points are arranged in the vertical direction in the isothermal platform;Sealing cover is arranged on the isothermal platform, and nitrogen is introduced into the sealing cover to block air;The test base and the side of the isothermal platform are wrapped with a heat preservation layer;

[0010] Ice adhesion strength measuring module includes the elastic coating arranged on the surface of isothermal platform and the mold placed on the surface of elastic coating, and the central points of the two sides of the mold are connected with corresponding remote tension gauge through traction line, and each remote tension gauge is arranged on the moving platform;

[0011] The control system controls the refrigerating capacity of the refrigeration unit through the temperature feedback of liquid inlet temperature measuring point, liquid outlet temperature measuring point and isothermal platform temperature measuring point, so as to maintain the temperature of the surface of isothermal platform constant at the set test temperature, controls the movement of two moving platforms through the tension feedback of two remote tension gauges, so as to control the tension of ice block to change periodically according to the setting, finally collects and records data and calculates ice adhesion strength.

[0012] Further, the front and back sides of the traction line are respectively provided with a vertical background plate and a parallel light source facing the background plate, and the angle between the traction line and the horizontal plane is determined by irradiating the traction line with the parallel light source.

[0013] Further, the three isothermal platform temperature measuring points are used to calculate the surface temperature of the isothermal platform (102) according to the heat conduction law, and the specific process is as follows:

[0014] The temperature of the uniform temperature platform is kept constant on the upper and lower surfaces, and the heat transfer is only through heat conduction in the height direction, and there is no heat exchange in the four directions, and the temperature distribution is solved by using the Fourier heat conduction law to satisfy the heat conduction equation:

[0015]

[0016] The solution of the heat conduction equation is a linear function:

[0017] T(z)=az+b

[0018] Wherein, T(z) is the temperature distribution in the height direction, z is the coordinate in the height direction; a, b are constants;

[0019] Therefore, the surface temperature of the uniform temperature platform is obtained by fitting the function of the temperature of the temperature measuring point and the distribution position. The scheme avoids the influence of the contact thermal resistance in the traditional measurement method such as thermocouple, and reduces the influence of accidental error by using the function fitting method of multiple temperature measuring points.

[0020] Further, the motion platform comprises a three-dimensional displacement platform, an angle tilting platform and a remotely controllable electric displacement platform arranged in sequence from bottom to top, and the remotely transmitted tension meter is arranged on the remotely controllable electric displacement platform.

[0021] The remotely transmitted tension meter is used for measuring the tension of the mold; the remotely controllable electric displacement platform controls the displacement of the remotely transmitted tension meter to control the tension of the mold; the angle tilting platform is used for adjusting the angle of the remotely transmitted tension meter and the remotely controllable electric displacement platform, so that they are always parallel to the direction of the traction line; the three-dimensional displacement platform is used for adjusting the horizontal and vertical positions to form the required angle between the traction line and the horizontal plane.

[0022] Further, a microscope is arranged above the mold, and the microscope is used for measuring the micro displacement of the ice block and the microstructure change of the elastic coating at the adhesion position of the ice block and the elastic coating, so as to study the influence mechanism of the periodic external force on the ice adhesion strength.

[0023] Preferably, the test base is provided with a rotary and zigzag cooling liquid channel.

[0024] A method for measuring ice adhesion strength under the action of periodic external force, using the above-mentioned ice adhesion strength measuring device under the action of periodic external force, comprising the following steps:

[0025] S1, set the temperature and tension cycle mode, control the operation of the refrigerating unit and convey the refrigerating liquid through the cooling liquid channel in the test base, calculate the surface temperature of the uniform temperature platform through the temperature measuring point of the uniform temperature platform, compare with the set temperature and control the refrigerating capacity of the refrigerating unit according to the comparison result, so that the uniform temperature platform is stabilized at the test temperature;

[0026] S2, fix the elastic coating on the uniform temperature platform, place the mold on the elastic coating, drop water droplets on the elastic coating in the mold to form a water film, and wait for the water film to freeze into ice;

[0027] S3, control the height of the remotely controllable electric displacement table, and measure the angle between the projection of the traction line on the background plate under the illumination of the parallel light source and the horizontal line, and adjust the height to the test set angle;

[0028] S4, control the displacement of the remotely controllable electric displacement table with the remotely transmitted tension meter, measure the displacement of the ice block and the microstructure change of the elastic coating through the microscope, monitor the tension data of the remotely transmitted tension meter, control the tension to be periodically cycled in the set range for a set number of times, then gradually increase the tension until the mold is pulled off from the elastic coating, record the data of the remotely transmitted tension meter, and calculate the ice adhesion strength.

[0029] The ice adhesion strength is calculated according to the following formula:

[0030]

[0031] Wherein, σ T,cyc is the ice adhesion strength at temperature T, F cyc is the maximum tension recorded by the remotely transmitted tension meter when the mold is pulled off after the periodic external force, θ is the angle between the traction line and the horizontal plane, and S is the ice adhesion area in the mold.

[0032] Compared with the prior art, the present application has the following beneficial effects:

[0033] The present application precisely controls the test surface temperature to be stably set at any set temperature within a controllable range by controlling the system according to the temperature feedback of the temperature measuring point and using a high thermal conductivity uniform temperature platform material, thereby improving the accuracy and stability of the ice adhesion strength measurement data of the surface of the material to be measured.

[0034] The present application precisely controls the ice adhesion area, tension angle and test temperature by the coordinated work of the mold, motion platform and uniform temperature platform with the control system, effectively improves the diversity, operability and repeatability of the test, simulates the ice adhesion strength measurement under the periodic external force under the periodic action of the centrifugal force and gravity on the fan blade under the real conditions, and is an ice adhesion strength test system with wide application range, high measurement accuracy, strong universality, simple installation and convenient carrying. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 It is a structure schematic view of the present application of the ice adhesion strength measurement device of the elastic coating under the periodic external force.

[0036] Figure 2 It is a structure schematic view of the test base in the present application.

[0037] Figure 3 This is a schematic diagram showing the positional relationship between the parallel light source, the traction line, and the background plate in this invention.

[0038] Figure 4 This study analyzes the forces acting on wind turbine blades during icing in a real-world application scenario.

[0039] Figure 5 This is a flowchart of a method for measuring the ice adhesion strength of an elastic coating under periodic external force according to the present invention.

[0040] In the diagram: 101-Test base, 102-Temperature equalization platform, 103-Coolant channel, 104-Sealing groove, 105-Sealing strip, 106-Liquid inlet, 107-Liquid outlet, 108-Insulation layer, 109-Sealing cover, 201-Refrigeration unit, 202-Liquid inlet pipe, 203-Liquid inlet temperature measuring point, 204-Liquid outlet pipe, 205-Liquid outlet temperature measuring point, 301-Temperature equalization platform temperature measuring point 1, 302-Temperature equalization platform temperature measuring point 2, 303-Temperature equalization platform temperature... Measurement point 3, 4-Elastic coating, 5-Mold, 601-Traction line 1, 602-Traction line 2, 7-Background board, 8-Parallel light source, 901-Three-dimensional displacement stage 1, 905-Three-dimensional displacement stage 2, 902-Angle tilting platform 1, 906-Angle tilting platform 2, 903-Remotely controllable electric displacement stage 1, 907-Remotely controllable electric displacement stage 2, 904-Remotely transmit tension gauge 1, 908-Remotely transmit tension gauge 2, 10-Microscope, 11-Control system. Detailed Implementation

[0041] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be noted that the embodiments described below are intended to facilitate the understanding of the present invention and do not constitute any limitation thereof.

[0042] like Figures 1-3 As shown, a device for measuring the ice adhesion strength of an elastic coating under periodic external force includes:

[0043] The controllable low-temperature test platform includes a test base 101, a temperature equalization stage 102, a coolant channel 103, a sealing groove 104, a sealing strip 105, a liquid inlet 106, a liquid outlet 107, an insulation layer 108, and a sealing cover 109. The rotating and tortuous coolant channel 103 ensures sufficient heat exchange of the coolant within the test base 101. The surrounding area, except for the surface of the temperature equalization stage 102, is covered with an insulation layer 108, improving the controllable low-temperature test platform's accuracy. The temperature equalization stage 102 is made of copper, which has excellent thermal conductivity, ensuring uniform temperature distribution and precise temperature control on its surface. The sealing cover 109 is located on the upper surface of the test platform and is filled with nitrogen to reduce the impact of airborne water vapor condensation on the ice adhesion strength test.

[0044] The refrigeration system, the refrigeration unit 201 is connected with the controllable low temperature test platform through the liquid inlet pipe 202 and the liquid outlet pipe 204, the liquid inlet temperature measuring point 203 and the liquid outlet temperature measuring point 205 are arranged on the pipes respectively, the refrigerant temperature of the liquid inlet pipe and the liquid outlet pipe is monitored, the refrigeration capacity of the refrigeration unit 201 is adjusted according to the temperature difference between the surface temperature of the temperature equalizing table 102 and the set temperature calculated by the control system 11.

[0045] The temperature measuring point one 301, the temperature measuring point two 302 and the temperature measuring point three 303 are equidistantly distributed in the temperature equalizing table 102 in the vertical direction, according to the Fourier heat conduction law under the one-dimensional steady state of the constant physical property and the internal heat source, the temperature distribution function of the temperature equalizing table 102 along the height direction can be fitted:

[0046]

[0047] The solution of the heat conduction equation is a linear function:

[0048] T(z)=az+b

[0049] Wherein, T(z) is the temperature distribution in the height direction, z is the coordinate in the height direction, a and b are constants, and the surface temperature of the temperature equalizing table 102 is calculated, the temperature measurement method avoids the error caused by poor contact of the thermistor, and improves the accuracy and reliability of the temperature measurement of the temperature equalizing table surface.

[0050] The elastic coating 4 is arranged on the surface of the temperature equalizing table 102, and a new material such as elastic deicing coating is used for testing.

[0051] The mold 5 is placed on the surface of the elastic coating 4, water droplets are dripped from the top, and ice blocks with fixed bottom area are formed under the limitation of the mold 5, the variable of the test is controlled, and the analysis and calculation are facilitated.

[0052] The traction line one 601 and the traction line two 602 are connected with the hooks of the remote tension meter one 904 and the remote tension meter two 908 at the positive center of the side surface of the mold 5.

[0053] The background plate 7 is vertically located at a position of 5-15 cm close to the rear of the traction line, and the parallel light source 8 is vertically located at a position of 40-50 cm in front of the traction line, the parallel light emitted by the parallel light source 8 irradiates the traction line to produce a projection on the background plate 7, the angle formed by the projection and the horizontal plane can be measured to obtain the angle formed by the traction line and the horizontal plane, so as to further test the influence of the traction force at different angles on the ice adhesion strength.

[0054] The remote force transmitters 904, 908 are connected to the mold 5 through the traction line, measure the traction force of the ice block and transmit the data to the control system 11. The remote electric displacement tables 903, 907 are arranged below the remote force transmitters 904, 908, and are controlled by the control system 11 to drive the remote force transmitters 904, 908 to displace, the displacement speed is 0.5 mm / s in the traction cycle process, and is reduced to 0.2 mm / s when the traction reaches 80% of the set range, the displacement is immediately stopped when the traction reaches the set range, so as to ensure that the traction changes stably in the cycle process, and the error between the actual cycle range and the set range of the traction is controlled to be ±0.2 N, after the cycle process is completed, the displacement speed is kept at 0.5 mm / s in the traction and release process until the traction and release are stopped, and the traction force of the ice block is controlled. The three-dimensional displacement tables 901, 905 are arranged below the remote electric displacement tables, and adjust the position and height to ensure that the traction measurement has a suitable initial position and a required traction angle. The angle inclination platforms 902, 906 adjust the angles of the remote force transmitters 904, 908 to be parallel to the angle between the traction line and the horizontal plane, so as to ensure that the measured traction is the true traction value on the traction line, and the ice adhesion strength test module can simulate the periodic external force acting on the ice in reality, such as the stress on the fan blade covered with ice and the stress on the power transmission line covered with ice.

[0055] As shown in Figure 4 , the stress condition of the ice on the tip of the fan blade in reality is affected by the gravity and the centrifugal force, assuming that the distance between the gravity center of the ice and the rotation center is R, the angle between the blade and the vertical direction is α, the rotation speed of the blade is ω, and the mass of the ice is m, through force analysis, it can be obtained that the force on the ice in the radial direction exists the equation:

[0056] F r = ω 2 Rm+ mgcos α

[0057] α = ωt

[0058] There is an extreme value in the vertical direction:

[0059] F r,max = m(ω 2 R+ g)

[0060] F r,min = m(ω 2 R-g)

[0061] Take Siemens Gamesa SG 2.1-114 for example, its blade length is 57m, and its force range in vertical direction is 80.2m~99.82m (let the radial direction be the positive direction) at 12rpm, and the icing is affected by the gravity of the circular motion cycle.

[0062] Under the incentive of wind, a low-frequency and large-amplitude self-excited vibration of iced conductor is called icing galloping. For the icing on the conductor, the periodic force is affected by the gravity, air force, and inertia force.

[0063] The gravity is constant vertically downward, and the size is G=mg.

[0064] Air force Where C D is the drag coefficient, p a is the air density, is the wind speed, and A is the reference area (upwind cross-sectional area).

[0065] The conductor vibration is described by simple harmonic vibration, and the displacement change with time can be expressed as:

[0066] x(t) = A cos (ωt + φ)

[0067] Where x(t) is the change of position with time t, A is the amplitude, ω is the angular frequency, t is the time, and φ is the initial phase.

[0068] The acceleration expression is obtained by taking the second derivative of time:

[0069] a(t) = -ω 2 A cos (ωt)

[0070] The inertia force expression is:

[0071] F(t) = m·a(t) = -mω 2 A cos (ωt)

[0072] In actual situations, the influence of air force on icing can be ignored compared to the inertia force, so it can be considered that the conductor icing is affected by the periodic action of inertia force and gravity.

[0073] Through the linkage control of the remote-transmission tension gauge 904, the remote-transmission tension gauge 908, the remote-controlled electric displacement table 903, the remote-controlled electric displacement table 907 and the control system 11, in the case where the tension direction changes, after the test starts, one side of the remote-controlled displacement table drives the remote-transmission tension gauge to gradually reach the set value according to the scheme, and the other side keeps the traction line in a relaxed state. After stabilization, the controllable electric displacement table on the traction side is reversely displaced until the traction force on this side gradually decreases to 0. The remote-controlled electric displacement table on the opposite side starts to drive the remote-transmission tension gauge to gradually increase the tension to the set value. After stabilization, the reverse displacement is performed until the traction force on this side gradually decreases to 0. The process is repeated for a specified number of times, and the tension on one side gradually increases until the ice block is pulled off, and the ice adhesion under the periodic external force is measured.

[0074] In the case where the tension direction does not change, one side of the remote-controlled displacement table drives the remote-transmission tension gauge to gradually reach the set value according to the scheme, and the other side keeps the traction line in a relaxed state. After stabilization, the controllable electric displacement table on the traction side is reversely displaced until the traction force on this side gradually decreases to the set minimum value. The process is repeated for a specified number of times, and the tension gradually increases until the ice block is pulled off, and the ice adhesion under the periodic external force is measured.

[0075] In this way, the periodic external force cycle in the real situation can be simulated on a small scale, and the change of the ice adhesion under the periodic external force is studied.

[0076] The microscope 10 is arranged in the sealed cover 109, magnifies the microstructure of the bonding part of the ice block and the elastic coating 4, measures and records the micro displacement and deformation of the ice block in the periodic change process, and directly reads the micro displacement distance of the ice block under the influence of the tension in the cycle process through the calibrated microscope 10. The microstructure change of the coating at the bonding part of the elastic coating 4 is observed in the observation process, and then the action process and mechanism of the influence of the periodic external force on the ice adhesion are analyzed.

[0077] The control system 11 controls the refrigerating capacity of the refrigerating unit through the temperature feedback control of the liquid inlet temperature measuring point 203, the liquid outlet temperature measuring point 205 and the temperature measuring point of the uniform temperature table, and then maintains the temperature of the surface of the controllable low-temperature test platform at the set test temperature. The displacement of the remote-controlled electric displacement table 903 and the remote-controlled electric displacement table 907 is controlled through the tension feedback of the remote-transmission tension gauge 904 and the remote-transmission tension gauge 908, and then the tension on the ice block is controlled to be periodically changed according to the setting.

[0078] An automatic test method for ice adhesion under periodic external force, which adopts the test device described above and performs the following test steps:

[0079] Step S1: Set the temperature of the test, the range f and the number of cycles n and the change mode of the periodic change of the pulling force on the ice block in the control system 11.

[0080] Step S2: Place the elastic coating 4 on the surface of the uniform temperature table 102, and place the mold 5 above the elastic coating 4, while ensuring that the top surface of the elastic coating 4 is flat, free of impurities and scratches, and that the data measured is not affected by friction and other forces.

[0081] Step S3: Turn on the refrigeration system, wait for the control system 11 to control the surface temperature of the uniform temperature table 102 to stabilize at the set temperature, drop water droplets into the mold 5 to freeze into ice blocks with fixed shapes, and then close the sealing cover 109 and fill it with nitrogen to expel air, ensuring that the test process is not affected by the condensation of water vapor in the air.

[0082] Step S4: Set the parallel light source 8 and the background plate 7 vertically on both sides of the traction line, adjust the three-dimensional displacement table 901 and the three-dimensional displacement table 905 to move the pulling force test module, adjust the height and measure the angle between the projection of the traction line on the background plate 7 and the horizontal plane, so that it reaches the required angle θ, adjust the horizontal position to make the remote force gauge 904 and the remote force gauge 908 have a pulling force of 0, and adjust the position of the microscope 10 to make the zero scale line coincide with the edge of the ice block.

[0083] Step S5: Control the remote control electric displacement table 903 and the remote control electric displacement table 907 to drive the remote force gauge 904 and the remote force gauge 908 to move at a certain speed, while observing and recording the small displacement and microstructure changes of the ice block through the microscope 10, gradually increasing the pulling force until the mold 5 and the elastic coating 4 are pulled off after the pulling force on the traction line is periodically cycled within the set range for the set number of times, and recording the data of the remote force gauge 904 and the remote force gauge 908, with the maximum value being F cyc , and calculating the ice adhesion strength according to the ice area S in the mold:

[0084] The calculation formula of the ice adhesion strength is

[0085] If the ice block does not fall off during the cycle, it indicates that the measured pulling force is the ice adhesion force between the ice and the surface of the elastic coating 4, and the test result is considered valid; if the ice block falls off during the cycle, it indicates that the cycle range is set too large, and the test result is considered invalid, at which time the cycle range needs to be re-set according to the maximum pulling force recorded by the remote force gauge 904 and the remote force gauge 908 in this test and the pulling force at the time of pulling off, and then steps S2 to S5 are repeated.

[0086] Wherein, in step S1, no cycle setting is performed, steps S2 to S4 are repeated, and the pulling force is gradually increased in step S5 until the ice block is pulled off from the elastic coating, the data of the remote pulling force meter is recorded, the maximum value is F, and the ice adhesion strength is calculated according to the ice area S in the mold.

[0087] The calculation formula of the general ice adhesion strength under the action of the periodic external force is The ice adhesion strength σ under the action of the periodic external force is T,cyc Comparative analysis.

[0088] Wherein, the cycle setting in step S1 can be set in the control system 11 according to the stress mode of the ice block in the actual situation, so as to simulate the pulling force change mode, the pulling force angle, etc., and maximize the reduction of the state of the ice adhesion strength of the elastic coating under the action of the periodic external force in the actual application.

[0089] Wherein, with the cycle of the pulling force, the micro displacement distance of the ice block under the microscope 10 and the microstructure form of the bonding part of the elastic coating 4 are recorded, the change mode thereof is studied, the number of cycles and the size of the cycle pulling force are changed, the micro displacement distance of the ice block and the microstructure change difference under the action of different periodic external forces are studied, and the influence mechanism of the periodic external force on the ice adhesion strength of the elastic coating is studied combined with the data obtained in the final test.

[0090] The test device and the test method can obtain different test conditions by adjusting the height of the three-dimensional displacement table 901, the three-dimensional displacement table 905, the surface temperature of the uniform temperature table 102, the range and number of the pulling force cycle, and the types of the elastic coating 4, and have high operability, universality and repeatability.

[0091] The above-described embodiments have described the technical solutions and beneficial effects of the present application in detail, and it should be understood that the above-described embodiments are only specific embodiments of the present application, and are not used to limit the present application. Any modification, supplement and equivalent replacement made within the principle range of the present application shall be included in the protection range of the present application.

Claims

1. A device for measuring the ice adhesion strength of an elastic coating under periodic external force, characterized in that, It includes a cooling module, an ice adhesion strength measurement module, and a control system (11); The refrigeration module includes a refrigeration unit, a test base (101), and a temperature equalization platform (102). The temperature equalization platform (102) is set on the test base (101). The test base (101) is provided with a coolant channel (103), which is connected to the refrigeration unit. The inlet and outlet of the coolant channel (103) are provided with inlet temperature measuring points and outlet temperature measuring points. Three temperature equalization platform measuring points are arranged at equal intervals along the vertical direction inside the temperature equalization platform (102). A sealing cover (109) is set on the temperature equalization platform (102), and nitrogen gas is introduced into the sealing cover (109) to block air. The outside of the test base (101) and the sides of the temperature equalization platform (102) are covered with a heat insulation layer (108). The ice adhesion strength measurement module includes an elastic coating (4) set on the surface of the uniform temperature stage (102) and a mold (5) placed on the surface of the elastic coating (4). The center of both sides of the mold (5) is connected to the corresponding remote-transmitting force gauge through a traction line. Each remote-transmitting force gauge is set on the motion platform. The control system (11) controls the cooling capacity of the refrigeration unit through temperature feedback from the liquid inlet temperature measuring point, the liquid outlet temperature measuring point and the temperature measuring point of the temperature equalization platform, thereby maintaining the temperature of the surface of the temperature equalization platform (102) at the set test temperature. Through the tension feedback of two remotely transmit tension gauges, the movement of the two motion platforms is controlled, thereby controlling the tension on the ice block to change periodically according to the settings. Finally, the data is collected and recorded and the ice adhesion strength is calculated.

2. The device for measuring the ice adhesion strength of an elastic coating under periodic external force according to claim 1, characterized in that, The front and rear sides of the traction line are respectively provided with a vertically placed background plate (7) and a parallel light source (8) facing the background plate (7). The angle between the traction line and the horizontal plane is determined by the shadow formed by the parallel light source (8) illuminating the traction line.

3. The device for measuring the ice adhesion strength of an elastic coating under periodic external force according to claim 1, characterized in that, The three temperature measuring points on the temperature equalization stage were used to calculate the surface temperature of the temperature equalization stage (102) using the law of thermal conduction. The specific process is as follows: The temperature equalization platform (102) is wrapped with an insulation layer (108) on its sides, so that the temperature equalization platform (102) transfers heat only through heat conduction in the height direction, and there is no heat exchange in the surrounding directions. The temperature of the upper and lower surfaces remains constant. Applying Fourier's law of heat conduction to solve for the temperature distribution, the heat conduction equation is satisfied: The solution to the heat conduction equation is a linear function: T(z) = az + b Where T(z) is the temperature distribution along the height direction, z is the coordinate along the height direction; a and b are constants; Therefore, the surface temperature of the equalization stage is obtained by fitting the temperature of the temperature measuring point with the distribution location.

4. The device for measuring the ice adhesion strength of an elastic coating under periodic external force according to claim 1, characterized in that, The motion platform includes a three-dimensional displacement stage, an angle tilting platform and a remotely controllable electric displacement stage arranged from bottom to top, and a remotely transmitted force gauge is installed on the remotely controllable electric displacement stage. The remote-transmitting force gauge is used to measure the magnitude of the tension force on the mold (5); the remote-controlled electric displacement stage controls the magnitude of the tension force on the mold by controlling the displacement of the remote-transmitting force gauge; the angle tilting platform is used to adjust the angle of the remote-transmitting force gauge and the remote-controlled electric displacement stage to keep them parallel to the direction of the traction line; the three-dimensional displacement stage is used to adjust the horizontal and vertical positions so that the traction line forms the angle required for the test with the horizontal plane.

5. The device for measuring the ice adhesion strength of an elastic coating under periodic external force according to claim 1, characterized in that, A microscope (10) is provided above the mold (5). The microscope (10) is used to measure the minute displacement of the ice block and the microstructure changes of the elastic coating at the adhesion point between the ice block and the elastic coating, so as to study the influence mechanism of periodic external force on the ice adhesion strength.

6. The device for measuring the ice adhesion strength of an elastic coating under periodic external force according to claim 1, characterized in that, The test base (101) is provided with a rotating and tortuous coolant channel (103).

7. A method for measuring the adhesion strength of ice under periodic external force, characterized in that, The method for measuring the ice adhesion strength of an elastic coating under periodic external force as described in any one of claims 1 to 6 includes the following steps: S1, set the temperature and tensile cycle mode, control the operation of the refrigeration unit and deliver the refrigerant through the coolant channel in the test base, calculate the surface temperature of the temperature equalization platform through the temperature measuring point of the temperature equalization platform, compare it with the set temperature, and control the cooling capacity of the refrigeration unit according to the comparison result to stabilize the temperature equalization platform at the test temperature. S2, fix the elastic coating on the uniform temperature platform, place the mold on the elastic coating, add water droplets on the elastic coating inside the mold to form a water film, and wait for the water film to freeze into ice; S3 controls the height of the remotely controlled electric displacement stage and simultaneously measures the angle between the projection of the traction line onto the background board under parallel light source illumination and the horizontal line, adjusting the height to the test set angle. S4 controls the remotely controlled electric displacement stage to drive the displacement of the remotely transmitted tensile gauge. The displacement of the ice block and the microstructure changes of the elastic coating are measured by a microscope. The tensile data of the remotely transmitted tensile gauge is monitored. The tensile force is controlled to cycle within a set range for a set number of times. Then, the tensile force is gradually increased until the mold and the elastic coating are pulled apart. The data of the remotely transmitted tensile gauge is recorded, and the ice adhesion strength is calculated.

8. The method for measuring ice adhesion strength under periodic external force according to claim 7, characterized in that, Ice adhesion strength is calculated using the following formula: Where, σ T,cyc Let F be the ice adhesion strength at temperature T. cyc The maximum tensile force recorded by the remote data-transmitting tension gauge when the mold is pulled out after the application of periodic external force is θ, which is the angle between the traction line and the horizontal plane, and S is the ice-covered area inside the mold.

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