Low-temperature surface frost ice variable gravity growth characteristic regulation and control method and device based on rotation

Abstract

The invention discloses a low-temperature surface frost ice variable gravity growth characteristic regulation and control method and device based on rotation. The regulation and control device drives an experimental environment chamber and a dynamic balance regulation and control module to rotate through a rotation power source; a cold plate, refrigeration equipment and a heat exchanger are mounted in a transparent cabin body of the experimental environment cabin; one side surface of the cold plate forms a low-temperature experiment cold surface for carrying out low-temperature frost ice variable gravity growth characteristic experiment research; the refrigeration equipment is used for controlling the surface temperature of the low-temperature experiment cold surface; the heat dissipation module communicates with the heat exchanger; the control module is used for controlling the temperature of the semiconductor thermoelectric sheet and the temperature and humidity in the experimental environment chamber; the dynamic balance regulation and control module is used for controlling the rotating dynamic balance of the experimental environment chamber; the image acquisition equipment is opposite to the cold plate, rotates synchronously and is used for acquiring a frost ice growth characteristic image on the surface of the cold plate. The regulation and control device can simulate a variable gravity frosting environment, cold surface cold condensation frosting in the variable gravity environment is achieved, and an observation image of the frosting process is obtained.

Description

Technical Field

[0001] The present invention belongs to the technical field of experimental devices, and in particular relates to a method and device for controlling the variable gravity growth characteristics of frost and ice on a low-temperature surface based on rotation. Background Art

[0002] With the development of modern technology, a variety of small refrigeration equipment and cryogenic devices are used in near-Earth spacecraft or space stations. The temperature of these devices is often far below 0°C, which can easily lead to serious frost on the equipment surface. In the field of infrared stealth, frost can have a fatal adverse effect on the normal operation of the cold shield system; in the field of space station heat dissipation, frost can significantly increase the heat transfer resistance of the radiator surface, reducing heat transfer efficiency and increasing cooling costs. Some refrigeration and cold storage equipment in the space station will frost during use, and the accumulation of frost can affect the normal operation of the space station equipment. Therefore, in order to fundamentally solve the frost problem under variable gravity conditions, it is necessary to conduct frost experiments under variable gravity conditions and understand the frost characteristics under variable gravity environments.

[0003] In existing icing and frosting experimental systems, the observation of the frosting process and characteristic parameters of natural convection or forced convection under constant gravity conditions is mainly achieved by constructing environmental chambers with different conditions. There is a lack of observations on the frosting process and frosting characteristic parameters under variable gravity. The invention patent application with application number 202410322121.1 discloses a test system for the icing effect of the fairing cap under simulated real vibration conditions, which is used to study the anti-icing performance of the fairing cap, but this test system cannot be applied to experimental research on the icing and frosting mechanism. The invention patent application with application number 201921646405.7 discloses an experimental system for frosting on a cold surface. The frosted surface is placed on a water-cooled head connected to a low-temperature constant-temperature water tank, and the frosting process is filmed using a microscope and camera combination directly above. Since only the water-cooled head connected to the low-temperature constant-temperature water tank is used for cooling, the cooling process takes a long time and the temperature of the cold surface cannot be accurately controlled. The invention patent application with application number 202011564351.7 discloses a constant temperature frosting cold surface device based on PID control and its constant temperature control method. A computer containing a built-in PID control system is used to control the liquid nitrogen flow rate and the heating rod power to achieve constant temperature control of the low-temperature frosted cold surface. The frosted cold surface provided by the experimental device is in a constant gravity working condition, and the liquid nitrogen flow rate and the heating rod power are used to control the constant temperature of the cold surface. It cannot be expanded to a rotating variable gravity working condition. At the same time, the invention patent applications with application numbers 202011561566.3 and 202210331485.7 also have the same limitations.

[0004] In summary, the existing low-temperature surface icing and frosting experimental system has the following shortcomings: (1) it cannot simultaneously meet the conditions of a stable rotating variable gravity reference frame and the study of the mechanism of icing and frosting on low-temperature surfaces; (2) the moist cold air used is mostly forced convection, which may affect the icing and frosting on the surface. Summary of the Invention

[0005] In order to explore the principles and physical properties of the frosting process on cold surfaces under variable gravity conditions, the present invention provides a method and device for controlling the variable gravity growth characteristics of frost and ice on low-temperature surfaces based on rotation. The control device can simulate a variable gravity frosting environment, realize condensation and frosting on cold surfaces under a variable gravity environment, obtain observation images of the frosting process, and also change the cold plate conditions and experimental environment to achieve different research purposes.

[0006] In order to achieve the above object, the present invention adopts the following specific technical solutions: The present invention provides a device for controlling the variable gravity growth characteristics of frost and ice on a low-temperature surface based on rotation, the device comprising: load-bearing frame; A rotating power source is fixedly mounted on the carrying frame; The transmission assembly is connected to the rotary power source and is used to transmit the rotary power generated by the rotary power source to the experimental environment chamber and the dynamic balance control module to drive the experimental environment chamber and the dynamic balance control module to rotate, and realize the simulation of the variable gravity environment condition in the experimental environment chamber by adjusting the speed; The experimental environment chamber includes a transparent cabin body and a cold plate, refrigeration equipment and heat exchanger installed in the transparent cabin body; one side surface of the cold plate constitutes a low-temperature experimental cold surface for conducting experimental research on the variable gravity growth characteristics of low-temperature frost ice; the refrigeration equipment is used to control the surface temperature of the low-temperature experimental cold surface; The heat dissipation module is connected to the heat exchanger and is used to dissipate heat from the refrigeration equipment through the circulation of the coolant; The control module is fixedly installed on the top of the supporting frame and is used to control the temperature of the semiconductor thermoelectric chip and the temperature and humidity in the experimental environment chamber; The dynamic balance control module is connected to the transmission assembly and is used to control the rotational dynamic balance of the experimental environment chamber; The image acquisition device is fixedly installed on the dynamic balance control module, and is arranged relative to the cold plate and rotates synchronously with it, and is used to collect images of frost and ice growth characteristics on the cold plate surface.

[0007] Furthermore, the rotational power source includes a stepper motor and a motor drive module; the stepper motor is directly driven and controlled by the motor drive module.

[0008] Furthermore, the transmission assembly includes a coupling, a transmission shaft, a flange, a rotary bearing, a turntable and a fluid-guiding slip ring; The drive shaft passes through the middle of the fluid-guiding slip ring. The bottom end is fixedly connected to the output shaft of the stepper motor through a coupling, and the top end is fixedly connected to the turntable through a flange. The turntable is mounted on the supporting frame through a rotating bearing. The stepper motor transmits the rotational power to the drive shaft through the coupling, and then the drive shaft and flange transmit the rotational power to the turntable. The liquid-guiding slip ring is composed of a fixed lower part and a rotating upper part connected together, and is used to achieve the communication of coolant between the heat dissipation module and the heat exchanger; the rotating upper part is fixedly connected to the transmission shaft and rotates synchronously with the transmission shaft; the fixed lower part is fixedly mounted on the supporting frame; The transparent shell is fixedly installed on the turntable.

[0009] Furthermore, the bearing frame includes a motor bearing structure, a slip ring bearing structure, a bearing bracket, a frame structure, an aluminum disc and an optical experimental platform; The supporting bracket and the frame structure are both made of aluminum profiles and fixedly connected, and the bottom ends are fixedly connected to the top surface of the optical experimental platform; The motor bearing structure is fixedly connected to the bearing bracket; the stepper motor is hoisted on the motor bearing structure; The slip ring bearing structure is fixedly connected between the bearing bracket and the fixed part of the lower part of the liquid-guiding slip ring, and is used to support the liquid-guiding slip ring; The aluminum disc is fixedly connected to the top of the frame structure, and the fixed part with the electrical slip ring is fixed at the center; The turntable is mounted on the bearing bracket via a rotary bearing.

[0010] Furthermore, the control module includes a humidifier, a humidity controller, a DC regulated power supply, a 220V AC power supply, a temperature controller, a humidity control signal line, a humidity sensing signal line, a water vapor pipeline, a power line, a temperature control signal line, a temperature control DC voltage line, a thermocouple, and an electrical slip ring; The humidifier delivers water vapor to the experimental environment chamber through the water vapor pipeline to control the humidity in the experimental environment chamber; the humidity controller obtains the ambient humidity of the experimental environment chamber through the humidity sensor signal line, and outputs the humidity control on-off signal through the humidity control signal line to control the operation of the humidifier; The DC regulated power supply is connected to the 220V AC power supply, obtains the DC voltage output on-off signal through the temperature control signal line, and inputs the 12V DC voltage to the refrigeration equipment through the temperature control DC voltage line; The thermocouple is set between the cold plate and the refrigeration equipment to measure the temperature of the cold plate in real time. The temperature controller is connected to the thermocouple to collect the temperature of the cold surface in the experimental environment chamber and output the temperature control DC voltage on-off signal through the temperature control signal line to control the working state of the DC regulated power supply. The fixed and rotating parts of the electrical slip ring utilize the internal slip ring structure to achieve fixed and rotating dynamic connection of the humidity sensor signal line, water vapor pipeline, power line, temperature control signal line and temperature control DC voltage line; The water vapor pipeline is divided into a gas pipeline and a liquid pipeline. The gas pipeline passes the water vapor output by the humidifier into the experimental environment chamber, and the liquid pipeline discharges the condensed water generated in the water vapor pipeline to ensure that the pipeline is unobstructed.

[0011] Furthermore, the heat dissipation module includes a constant temperature water bath, a coolant low temperature pipeline and a coolant high temperature pipeline; The constant temperature water bath is used to provide low-temperature coolant, and the low-temperature coolant is passed into the heat exchanger through the coolant low-temperature pipeline. The high-temperature coolant after absorbing heat in the heat exchanger returns to the constant temperature water bath through the coolant high-temperature pipeline. The rotary sealing connection between the coolant low-temperature pipeline and the coolant high-temperature pipeline is realized through the fixed part and the rotating part of the liquid guide slip ring.

[0012] Furthermore, the refrigeration device is a semiconductor thermoelectric chip; the cold plate is a copper plate; the heat exchanger is a water-cooled heat exchanger; Thermal conductive silicone grease is applied between the semiconductor thermoelectric chip, the cold plate and the water-cooled heat exchanger.

[0013] Furthermore, the image acquisition device is a high-speed camera; The dynamic balance control module includes a slide, counterweight, supporting link and shock-absorbing bearing; The high-speed camera is fixedly mounted on the slide; The slide is fixedly connected to one end of the supporting link; The counterweight is fixedly connected to the other end of the supporting link; The supporting link is connected to the shock-absorbing load through bolts and rubber washers; the shock-absorbing load is fixedly installed on the top of the turntable to ensure the longitudinal single-degree-of-freedom movement of the high-speed camera.

[0014] In addition, the present invention also provides a method for controlling the variable gravity growth characteristics of frost ice on a low-temperature surface. The method is implemented using the above-mentioned control device and includes the following steps: Step 1: Set the experimental working condition parameters. Determine the material and surface characteristics of the low-temperature experimental cold surface according to the experimental working conditions, set the target cooling temperature and target heating temperature of the refrigeration equipment, set the target speed of the rotary power source according to the designed experimental working conditions and the rotation radius of the low-temperature experimental cold surface, and set the target humidity of the experimental environment chamber. Step 2: Set the mass of the counterweight according to the experimental conditions and perform dynamic balancing using the counterweight; Step 3: Control the rotary power source to start rotating. After the rotary power source reaches the target speed and operates stably, switch the working state of the refrigeration device to the cooling mode, conduct the experiment and use an image acquisition device to record the video; Step 4: After completing the experimental working condition experiment, the rotation power source is controlled to stop rotating, the video recording of the image acquisition device is stopped, and the refrigeration device is switched to a heating working state to evaporate the water; Step 5: Process and analyze the collected video data to analyze the frost and ice growth characteristics under rotating variable gravity conditions.

[0015] Furthermore, in step five, the frost ice growth characteristics include droplet condensation and freezing time, frost branch growth start time, frost layer thickness dynamic change curve, dynamic frost rate curve, frost layer surface roughness and frost layer surface inverted melting characteristic parameters.

[0016] Compared with the prior art, the technical solution of the present invention has the following beneficial effects: The low-temperature surface frost and ice variable gravity growth characteristic control device of the present invention utilizes a rotary power source to generate rotary power, and transmits the rotary power to the experimental environment cabin through a transmission component, thereby driving the experimental environment cabin to rotate through the rotary power source, and simulating the variable gravity environment working condition in the experimental environment cabin by adjusting the speed of the rotary power source, and controlling the rotational dynamic balance of the experimental environment cabin through a dynamic balance control module, and utilizing the cold plate, refrigeration equipment and heat exchanger in the experimental environment cabin to realize the variable gravity growth of frost and ice on the cold surface of the low-temperature experiment, and collecting the image of the frost and ice growth characteristic of the cold plate surface through the image acquisition equipment; and realizing the natural convection of the air flow near the cold surface where frosting occurs through the closed experimental environment cabin; therefore, the control device can simulate the variable gravity frosting environment, realize the condensation and frosting of the cold surface in the variable gravity experimental environment, obtain the observation image of the frosting process, and also can change the cold plate conditions and the experimental environment to achieve different research purposes. The experimental system composed of the above-mentioned control device has high integration, small space occupation, low cost, easy operation, and is convenient for conducting research work in the laboratory; at the same time, the use of the above-mentioned control device can observe and adjust relevant parameters in the experimental environment chamber in real time during the rotation of the experimental environment chamber, such as the cold plate temperature, relative humidity, etc., making the experimental data more accurate; the environmental parameter control systems such as the cold plate surface temperature control and the relative humidity of the experimental environment chamber are independent of the rotating part, and the parameters can be adjusted during the rotation of the experimental environment chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the principle of the device for controlling the variable gravity growth characteristics of frost and ice on a low-temperature surface according to the present invention; Figure 2 This is a schematic structural diagram of the device for controlling variable gravity growth characteristics of frost and ice on a low-temperature surface according to the present invention; Figure 3 for Figure 2 Schematic diagram of the structure of the experimental environment chamber; Figure 4The frost thickness variation curve under different working conditions is extracted based on the original video data obtained by the image acquisition device.

[0018] Among them, 1-rotating power source; 2-transmission assembly; 3-carrying frame; 4-control module; 5-heat dissipation module; 6-experimental environment chamber; 7-image acquisition device; 8-dynamic balance control module; 101-stepping motor; 102-motor drive module; 103-programmable controller; 201-coupling; 202-transmission shaft; 203-flange; 204-rotating bearing; 205-turntable; 206-liquid guide slip ring; 301-motor bearing structure; 302-slip ring bearing structure; 303-carrying bracket; 304-frame structure; 305-aluminum disc; 306-optical experimental platform; 401-humidifier; 402-humidity controller; 403-DC regulated power supply; 4 04-220V AC power supply; 405-temperature controller; 406-humidity control signal line; 407-humidity sensor signal line; 408-water vapor pipeline; 408G-gas pipeline; 408L-liquid pipeline; 409-power line; 410-temperature control signal line; 411-temperature control DC voltage line; 412-thermocouple; 413-electrical slip ring; 501-constant temperature water bath; 502-coolant low-temperature pipeline; 503-coolant high-temperature pipeline; 601-transparent cabin; 602-cold plate; 603-refrigeration equipment; 604-heat exchanger; 701-high-speed camera; 801-slide table; 802-counterweight; 803-support link; 804-shock absorber. DETAILED DESCRIPTION

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] Example 1 like Figure 1 and Figure 2 As shown, this embodiment provides a rotation-based control device for the variable gravity growth characteristics of frost and ice on a low-temperature surface. The control device constitutes an experimental system and includes a rotational power source 1, a transmission assembly 2, a supporting frame 3, a control module 4, a heat dissipation module 5, an experimental environment chamber 6, an image acquisition device 7, and a dynamic balance control module 8; wherein: The supporting frame 3 includes a motor supporting structure 301, a slip ring supporting structure 302, a supporting bracket 303, a frame structure 304, an aluminum disc 305 and an optical experimental platform 306; the supporting bracket 303 and the frame structure 304 are both composed of aluminum profiles fixedly connected, and the bottom ends are fixedly connected to the top surface of the optical experimental platform 306; the motor supporting structure 301 is fixedly connected to the supporting bracket 303; the stepper motor 101 is hoisted to the motor supporting structure 301 using bolts and T-nuts; the slip ring supporting structure 302 is fixedly connected between the supporting bracket 303 and the fixed part of the lower part of the liquid guide slip ring 206, for supporting the liquid guide slip ring 206; the fixed part of the lower part of the liquid guide slip ring 206 is connected and fixed to the slip ring supporting structure 302 using bolts and T-nuts, and the slip ring supporting structure 302 is connected and fixed to the supporting bracket 303 using 20mm aluminum profile connectors. The aluminum disc 305 is fixedly connected to the top of the frame structure 304, with the fixed portion of the electrical slip ring 413 fixedly mounted at the center. The turntable 205 is mounted to the support bracket 303 via the rotary bearing 204. The motor support structure 301 and the slip ring support structure 302 are both made of 20mm aluminum profiles and are fixed together using 20mm aluminum profile connectors. The support bracket 303 is made of 30mm aluminum profiles. 30mm aluminum profile connectors are used to connect and secure aluminum profiles of different lengths. Bolts and some of the aluminum profile connectors are used to connect and secure the optical experimental platform 306. The frame structure 304 is composed of 40mm aluminum profiles. 40mm aluminum profile connectors are used to connect and secure aluminum profiles of different lengths. Bolts and some of the aluminum profile connectors are used to connect and secure the optical experimental platform 306. The aluminum disc 305, with a diameter of 600mm and a thickness of 5mm, is fixed to the frame structure 304 using bolts and T-nuts. The aluminum disc 305 has four through holes evenly distributed in the circumferential direction at the center thereof. The fixed portion of the electrical slip ring 413 is connected and fixed to the aluminum disc 305 using bolts, spring washers and nuts.

[0021] The rotational power source 1 is fixedly mounted on the supporting frame 3. The rotational power source 1 provides rotational power for the experimental system and includes a stepper motor 101, a motor driver module 102, and a programmable controller 103. The stepper motor 101 is directly driven and controlled by the motor driver module 102. Alternatively, the rotational power source 1 can be a small internal combustion engine. The motor driver module 102 can adjust the operating frequency of the stepper motor 101 and can coordinate with the programmable controller 103 to control the stepper motor 101. The programmable controller 103 can programmatically control the operating state of the stepper motor 101. Specifically, the speed of the stepper motor 101 can be set to 0 rpm, 10 rpm, or 30 rpm.

[0022] The transmission assembly 2 is connected to the rotary power source 1 for transmitting the rotary power generated by the rotary power source 1 to the experimental environment chamber 6 and the dynamic balance control module 8, so as to drive the experimental environment chamber 6 and the dynamic balance control module 8 to rotate, and realize the simulation of the variable gravity environment working condition in the experimental environment chamber 6 by speed adjustment; specifically, the transmission assembly 2 includes a coupling 201, a transmission shaft 202, a flange 203, a rotary bearing 204, a turntable 205 and a liquid guide slip ring 206; the transmission shaft 202 passes through the middle of the liquid guide slip ring 206, and the bottom end is fixedly connected to the output shaft of the stepper motor 101 through the coupling 201, and the top end is fixedly connected to the turntable 205 through the flange 203; there are 6 unevenly distributed through holes between the flange 203 and the turntable 205, which are connected using bolts, spring washers and nuts. The turntable 205 is mounted on the supporting frame 3 via a rotating bearing 204. The rotating bearing 204 serves as the connection between the rotating and fixed components of the experimental system and also bears the load on the turntable 205. Twelve through-holes, evenly distributed around the circumference, are provided at corresponding locations between the turntable 205 and the rotating bearing 204. These holes are connected using bolts, flat washers, spring washers, and nuts. Bolts, rubber washers, and T-nuts are used to connect the rotating bearing 204 to the supporting frame 303. After the target command is input via the programmable controller 103, the stepper motor 101 begins operating according to the command. The stepper motor 101 transmits rotational power to the drive shaft 202 via the coupling 201. The drive shaft 202 and flange 203 then transmit the rotational power to the turntable 205. The liquid-guiding slip ring 206 has a centrally located structure, allowing the drive shaft 202 to pass through it. It consists of a lower fixed portion and an upper rotating portion that are connected together, and is used to connect the coolant between the heat dissipation module 5 and the heat exchanger 604. The upper rotating portion is fixedly connected to the drive shaft 202 via long bolts and rotates synchronously with the drive shaft 202. The lower fixed portion is fixedly mounted to the support frame 3 via bolts and T-nuts. The transparent cabin is fixedly mounted to the turntable 205. The drive shaft 202 has keyways at its connection ends with the coupling 201 and flange 203. The coupling 201 and flange 203 also have similar keyways, connecting to the drive shaft 202 via the keyways to transmit power.

[0023] like Figure 3As shown, the experimental environment chamber 6 includes a transparent cabin 601 and a cold plate 602, a refrigeration device 603 and a heat exchanger 604 installed in the transparent cabin 601; the transparent cabin 601 is fixedly installed on the turntable 205 and rotates synchronously with the turntable 205 under the drive of the rotary power source 1; a sealed space is formed in the transparent cabin 601; the cold plate 602, the refrigeration device 603 and the heat exchanger 604 are all installed in the transparent cabin 601; one side surface of the cold plate 602 constitutes a low-temperature experimental cold surface for conducting experimental research on the variable gravity growth characteristics of low-temperature frost ice; the refrigeration device 603 is used to control the surface temperature of the low-temperature experimental cold surface; in this embodiment, Refrigeration equipment 603 uses a semiconductor thermoelectric chip, cold plate 602 uses a copper plate, and heat exchanger 604 uses a water-cooled heat exchanger. The hot end of the semiconductor thermoelectric chip is connected to cold plate 602, and the hot end is connected to water-cooled heat exchanger 604. Thermal grease is applied between the semiconductor thermoelectric chip, cold plate 602, and water-cooled heat exchanger 604. Cold plate 602 measures 40 mm × 40 mm × 3 mm. A thermocouple 412 is embedded between cold plate 602 and the semiconductor thermoelectric chip to measure the temperature of cold plate 602 in real time. Water-cooled heat exchanger 604 is connected to a constant temperature water bath 501 via a low-temperature coolant line 502 and a high-temperature coolant line 503. The cold surface used in low-temperature experiments can be made of various materials, such as copper and aluminum, and can have varying surface properties, such as hydrophilic or hydrophobic. The cooling element is the source of cooling for the cryogenic experimental cold surface, controlling the surface temperature to a target value and maintaining stability. The cooling element can be a small refrigeration device such as a semiconductor refrigeration element. A cooling medium is passed through heat exchanger 604 to absorb the heat generated by the cooling element. Heat exchanger 604 can be a microchannel heat exchanger or other heat exchange device.

[0024] The heat dissipation module 5 is connected to the heat exchanger 604 of the experimental environment chamber 6, and is used to achieve heat dissipation of the refrigeration equipment 603 through the circulation of coolant; the heat dissipation module 5 includes a constant temperature water bath 501, a low-temperature coolant pipeline 502 and a high-temperature coolant pipeline 503; the constant temperature water bath 501 is used to provide low-temperature coolant, and pass the low-temperature coolant into the heat exchanger 604 through the low-temperature coolant pipeline 502, and the high-temperature coolant after absorbing heat in the heat exchanger 604 returns to the constant temperature water bath 501 through the high-temperature coolant pipeline 503; the rotary sealing connection between the low-temperature coolant pipeline and the high-temperature coolant pipeline is realized by the fixed part and the rotating part of the liquid guide slip ring 206.

[0025] The control module 4 is fixedly mounted on the top of the supporting frame 3 and is used to control the temperature of the semiconductor thermoelectric element as well as the temperature and humidity in the experimental environment chamber 6. The control module 4 is used to control the temperature changes of the cold surface of the low-temperature experiment and the changes of environmental parameters such as temperature and humidity in the experimental environment chamber 6. It can use devices such as a PID controller and a DC power supply to achieve closed-loop control to maintain parameter stability. The control module 4 includes a humidifier 401, a humidity controller 402, a DC regulated power supply 403, a 220V AC power supply 404, a temperature controller 405, a humidity control signal line 406, a humidity sensor signal line 407, a water vapor pipeline 408, a power line 409, a temperature control signal line 410, a temperature control DC voltage line 411, a thermocouple 412, and an electrical slip ring 413. The humidifier 401 is connected to the 220V AC power supply 404 via the power line 409 to obtain operating power, receives an operating on / off signal from the humidity controller 402, and transports water vapor into the experimental environment chamber 6 via the water vapor pipeline 408 to maintain humidity stability. Both humidity controller 402 and temperature controller 405 can be industrial PID closed-loop controllers and are connected to a 220V AC power source 404 via power line 409 for operating power. Humidity controller 402 detects the ambient humidity of experimental environment chamber 6 via humidity sensor signal line 407 and outputs a humidity control on / off signal via humidity control signal line 406 to control the operation of humidifier 401. A DC regulated power supply 403, connected to a 220V AC power source 404 via power line 409, generates operating power and outputs a 12V DC voltage. It receives a DC voltage output on / off signal via temperature control signal line 410 and inputs the 12V DC voltage to refrigeration equipment 603 via temperature control DC voltage line 411. The thermocouple 412 is arranged between the cold plate 602 and the refrigeration equipment 603 for real-time measurement of the temperature of the cold plate 602; the temperature controller 405 is connected to the thermocouple 412 for collecting the cold surface temperature in the experimental environment chamber 6 and outputting a temperature control DC voltage on-off signal through the temperature control signal line 410 to control the working state of the DC regulated power supply 403. The fixed portion of the electrical slip ring 413 is fixed to the aluminum disc 305 using bolts, spring washers, and nuts. The fixed and rotating portions of the electrical slip ring 413 utilize an internal slip ring structure to achieve a fixed and rotational dynamic connection between the humidity sensing signal line 407, the water vapor pipeline 408, the power line 409, the temperature control signal line 410, and the temperature control DC voltage line 411. The fixed portion of the electrical slip ring 413 is respectively connected to the humidity sensing signal line 407, the water vapor pipeline 408, the power line 409, the temperature control signal line 410, and the temperature control DC voltage line 411. The rotating portion of the electrical slip ring 413 utilizes an internal slip ring structure to connect to the humidity sensing signal line 407, the water vapor pipeline 408, the power line 409, the temperature control signal line 410, and the temperature control DC voltage line 411, thereby achieving a fixed and rotational dynamic connection between the electrical signal and the water vapor.The water vapor pipeline 408 is divided into a gas pipeline 408G and a liquid pipeline 408L. The gas pipeline 408G passes the water vapor output by the humidifier 401 into the experimental environment chamber 6, and the liquid pipeline 408L discharges the condensed water generated in the water vapor pipeline 408 out of the pipeline to ensure that the pipeline is unobstructed.

[0026] Image acquisition device 7 can be a high-speed camera 701, a SLR camera, a mirrorless camera, or an industrial camera. It is fixedly mounted on the dynamic balancing control module 8 and positioned relative to and rotating synchronously with the cold plate 602. It is used to capture images of frost growth characteristics on the cold plate 602. Image acquisition device 7 is used to obtain images of frost growth characteristics on the experimental cold surface. Image acquisition device 7 is fixedly connected to the dynamic balancing control module 8, maintaining relative stationary position and synchronous rotation with the experimental environment chamber 6. The dynamic balance control module 8 is connected to the transmission assembly 2 and is used to control the rotational dynamic balance of the experimental environment chamber 6. The dynamic balance control module 8 includes a slide 801, a counterweight 802, a support link 803, and a shock-absorbing bearing 804. The high-speed camera 701 is fixed to the slide 801 using studs. The slide 801 is fixedly connected to one end of the support link 803 using bolts and T-nuts. The counterweight 802 is fixedly connected to the other end of the support link 803 using bolts and T-nuts. The support link 803 is connected to the shock-absorbing bearing 804 via bolts and rubber washers. The shock-absorbing bearing 804 is fixed to the top of the aluminum turntable 205 using studs to ensure the longitudinal single-degree-of-freedom motion of the high-speed camera 701. The mass of the counterweight 802 is adjustable, and by changing the mass of the counterweight 802, the rotational dynamic balance of the experimental environment chamber 6 can be adjusted under different experimental conditions.

[0027] The above-mentioned low-temperature surface frost and ice variable gravity growth characteristic control device uses a rotary power source 1 to generate rotary power, and transmits the rotary power to the experimental environment chamber 6 through the transmission component 2, so that the experimental environment chamber 6 is driven to rotate by the rotary power source 1, and the variable gravity environment working condition is simulated in the experimental environment chamber 6 by adjusting the speed of the rotary power source 1, and the rotational dynamic balance of the experimental environment chamber 6 is controlled by the dynamic balance control module 8. The cold plate 602, refrigeration equipment 603 and heat exchanger 604 in the experimental environment chamber 6 are used to realize the variable gravity growth of frost and ice on the cold surface of the low-temperature experiment, and the image of the frost growth characteristic of the surface of the cold plate 602 is collected by the image acquisition device 7. Therefore, the control device can simulate the variable gravity frosting environment, realize the condensation and frosting of the cold surface in the variable gravity experimental environment, and obtain the observation image of the frosting process. The conditions of the cold plate 602 and the experimental environment can also be changed to achieve different research purposes. The experimental system composed of the above-mentioned control device has high integration, small space occupation, low cost, easy operation, and is convenient for conducting research work in the laboratory; at the same time, the use of the above-mentioned control device can observe and adjust relevant parameters in the experimental environment chamber 6 in real time during the rotation of the experimental environment chamber 6, such as the temperature and relative humidity of the cold plate 602, so that the experimental data is more accurate; the control system of environmental parameters such as the surface temperature control of the cold plate 602 and the relative humidity of the experimental environment chamber 6 is independent of the rotating part, and the parameters can be adjusted during the rotation of the experimental environment chamber 6.

[0028] Example 2 This embodiment provides a method for controlling the variable gravity growth characteristics of frost and ice on a low-temperature surface. The method is implemented using the control device in the first embodiment. The method includes the following steps: Step 1: Set the experimental operating parameters. The material and surface properties of the cryogenic experimental cold surface are determined based on the experimental conditions. The installation parameters of the cryogenic experimental cold surface, the target cooling temperature, and the target heating temperature of the refrigeration equipment 603 are set. The target speed of the rotary power source 1 and the target humidity of the experimental environmental chamber 6 are set based on the designed experimental conditions and the rotation radius of the cryogenic experimental cold surface. The installation parameters of the cryogenic experimental cold surface include the installation method, such as whether the cold surface faces outward, inward, vertical, or tilted. The cooling temperature of the cryogenic experimental cold surface can be set to -25°C, the target relative humidity can be 45%, and the target heating temperature of the refrigeration equipment 603 can be 30°C.

[0029] Step 2: Set the mass of the counterweight 802 according to the experimental working conditions, and perform dynamic balancing through the counterweight 802; while performing dynamic balancing, the operational safety of the experimental system can also be checked, including: checking that the water vapor pipeline 408, the coolant low-temperature pipeline 502, and the coolant high-temperature pipeline 503 are connected normally, that there is no leakage of the cooling and heat dissipation medium, confirming that the refrigeration equipment 603 is in the heating working state, confirming that the experimental environment chamber 6 is in a relatively closed state, and that the temperature, humidity and other parameter measurement equipment are working normally under manual rotation at low speed.

[0030] Step 3: Control the rotary power source 1 to start rotating. After the rotary power source 1 reaches the target speed and runs stably, and the relevant environmental parameters of the experimental environment chamber 6 are stable, switch the working state of the refrigeration device 603 to the cooling mode, conduct the experiment, and use the image acquisition device 7 to record the video; Step 4: After completing the experimental working condition experiment, control the rotating power source 1 to stop rotating. After the experimental system stops rotating and stabilizes, stop the video recording of the image acquisition device 7, switch the refrigeration equipment 603 to the heating working state, and evaporate the moisture on the surface of the cold plate 602.

[0031] Step five: Process and analyze the collected video data to analyze the frost growth characteristics under rotating variable gravity conditions. The frost growth characteristics include the droplet condensation and freezing time, the time when frost branches begin to grow, the dynamic change curve of frost layer thickness, the dynamic frost rate curve, the frost layer surface roughness and the frost layer surface inverted melting characteristic parameters, etc.

[0032] According to the above method, the experiment was conducted, the frost formation time was set to 30 minutes, the actual frost growth time was 1600 seconds, and the original video data was obtained by shooting to extract the frost thickness change curve under different working conditions. Figure 4 shown.

[0033] Obviously, those skilled in the art may make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the present invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is intended to include such modifications and variations.

Claims

1. A device for controlling the variable gravity growth characteristics of frost and ice on a low-temperature surface based on rotation, characterized in that: include: load-bearing frame; A rotating power source is fixedly mounted on the carrying frame; The transmission assembly is connected to the rotary power source and is used to transmit the rotary power generated by the rotary power source to the experimental environment chamber and the dynamic balance control module to drive the experimental environment chamber and the dynamic balance control module to rotate, and realize the simulation of the variable gravity environment condition in the experimental environment chamber by adjusting the speed; The experimental environment chamber includes a transparent cabin body and a cold plate, refrigeration equipment and heat exchanger installed in the transparent cabin body; one side surface of the cold plate constitutes a low-temperature experimental cold surface for conducting experimental research on the variable gravity growth characteristics of low-temperature frost ice; the refrigeration equipment is used to control the surface temperature of the low-temperature experimental cold surface; The heat dissipation module is connected to the heat exchanger and is used to dissipate heat from the refrigeration equipment through the circulation of the coolant; The control module is fixedly installed on the top of the supporting frame and is used to control the temperature of the semiconductor thermoelectric chip and the temperature and humidity in the experimental environment chamber; The dynamic balance control module is connected to the transmission assembly and is used to control the rotational dynamic balance of the experimental environment chamber; The image acquisition device is fixedly installed on the dynamic balance control module, and is arranged relative to the cold plate and rotates synchronously with it, and is used to collect images of frost and ice growth characteristics on the cold plate surface.

2. The control device according to claim 1, characterized in that: The rotational power source includes a stepper motor and a motor drive module; the stepper motor is directly driven and controlled by the motor drive module.

3. The control device according to claim 2, characterized in that: The transmission assembly includes a coupling, a transmission shaft, a flange, a rotary bearing, a turntable and a fluid-guiding slip ring; The drive shaft passes through the middle of the fluid-guiding slip ring. The bottom end is fixedly connected to the output shaft of the stepper motor through a coupling, and the top end is fixedly connected to the turntable through a flange. The turntable is mounted on the supporting frame through a rotating bearing. The stepper motor transmits the rotational power to the drive shaft through the coupling, and then the drive shaft and flange transmit the rotational power to the turntable. The liquid-guiding slip ring is composed of a fixed lower part and a rotating upper part connected together, and is used to achieve the communication of coolant between the heat dissipation module and the heat exchanger; the rotating upper part is fixedly connected to the transmission shaft and rotates synchronously with the transmission shaft; the fixed lower part is fixedly mounted on the supporting frame; The transparent cabin is fixedly installed on the turntable.

4. The control device according to claim 3, characterized in that: The bearing frame includes a motor bearing structure, a slip ring bearing structure, a bearing bracket, a frame structure, an aluminum disc and an optical experimental platform; The supporting bracket and the frame structure are both made of aluminum profiles and fixedly connected, and the bottom ends are fixedly connected to the top surface of the optical experimental platform; The motor bearing structure is fixedly connected to the bearing bracket; the stepper motor is hoisted on the motor bearing structure; The slip ring bearing structure is fixedly connected between the bearing bracket and the fixed part of the lower part of the liquid-guiding slip ring, and is used to support the liquid-guiding slip ring; The aluminum disc is fixedly connected to the top of the frame structure, and the fixed part with the electrical slip ring is fixed at the center; The turntable is mounted on the bearing bracket via a rotary bearing.

5. The control device according to claim 4, characterized in that: The control module includes a humidifier, a humidity controller, a DC regulated power supply, a 220V AC power supply, a temperature controller, a humidity control signal line, a humidity sensor signal line, a water vapor pipeline, a power line, a temperature control signal line, a temperature control DC voltage line, a thermocouple and an electrical slip ring; The humidifier delivers water vapor to the experimental environment chamber through the water vapor pipeline to control the humidity in the experimental environment chamber; the humidity controller obtains the ambient humidity of the experimental environment chamber through the humidity sensor signal line, and outputs the humidity control on-off signal through the humidity control signal line to control the operation of the humidifier; The DC regulated power supply is connected to the 220V AC power supply, obtains the DC voltage output on-off signal through the temperature control signal line, and inputs the 12V DC voltage to the refrigeration equipment through the temperature control DC voltage line; The thermocouple is set between the cold plate and the refrigeration equipment to measure the temperature of the cold plate in real time. The temperature controller is connected to the thermocouple to collect the temperature of the cold surface in the experimental environment chamber and output the temperature control DC voltage on-off signal through the temperature control signal line to control the working state of the DC regulated power supply. The fixed and rotating parts of the electrical slip ring utilize the internal slip ring structure to achieve fixed and rotating dynamic connection of the humidity sensor signal line, water vapor pipeline, power line, temperature control signal line and temperature control DC voltage line; The water vapor pipeline is divided into a gas pipeline and a liquid pipeline. The gas pipeline passes the water vapor output by the humidifier into the experimental environment chamber, and the liquid pipeline discharges the condensed water generated in the water vapor pipeline to ensure that the pipeline is unobstructed.

6. The control device according to claim 5, characterized in that: The heat dissipation module includes a constant temperature water bath, a coolant low temperature pipeline and a coolant high temperature pipeline; The constant temperature water bath is used to provide low temperature coolant, and the low temperature coolant is passed into the heat exchanger through the coolant low temperature pipeline. The high temperature coolant after absorbing heat in the heat exchanger returns to the constant temperature water bath through the coolant high temperature pipeline. The rotary sealing connection between the coolant low-temperature pipeline and the coolant high-temperature pipeline is achieved through the fixed part and the rotating part of the liquid guide slip ring.

7. The control device according to claim 6, characterized in that: The refrigeration equipment is a semiconductor thermoelectric chip; the cold plate is a copper plate; the heat exchanger is a water-cooled heat exchanger; Thermal conductive silicone grease is applied between the semiconductor thermoelectric chip, the cold plate and the water-cooled heat exchanger.

8. The control device according to claim 7, characterized in that: The image acquisition device is a high-speed camera; The dynamic balance control module includes a slide, counterweight, supporting link and shock-absorbing bearing; The high-speed camera is fixedly mounted on the slide; The slide is fixedly connected to one end of the supporting link; The counterweight is fixedly connected to the other end of the supporting link; The supporting link is connected to the shock-absorbing load through bolts and rubber washers; the shock-absorbing load is fixedly installed on the top of the turntable to ensure the longitudinal single-degree-of-freedom movement of the high-speed camera.

9. A method for controlling the variable gravity growth characteristics of frost ice on a low-temperature surface, characterized in that: The control device according to claim 8 is used to implement the method, comprising the following steps: Step 1: Set the experimental working condition parameters. Determine the material and surface characteristics of the low-temperature experimental cold surface according to the experimental working conditions, set the target cooling temperature and target heating temperature of the refrigeration equipment, set the target speed of the rotary power source according to the designed experimental working conditions and the rotation radius of the low-temperature experimental cold surface, and set the target humidity of the experimental environment chamber. Step 2: Set the mass of the counterweight according to the experimental conditions and perform dynamic balancing using the counterweight; Step 3: Control the rotary power source to start rotating. After the rotary power source reaches the target speed and operates stably, switch the working state of the refrigeration device to the cooling mode, conduct the experiment and use an image acquisition device to record the video; Step 4: After completing the experimental working condition experiment, the rotation power source is controlled to stop rotating, the video recording of the image acquisition device is stopped, and the refrigeration device is switched to a heating working state to evaporate the water; Step 5: Process and analyze the collected video data to analyze the frost and ice growth characteristics under rotating variable gravity conditions.

10. The control method according to claim 9, characterized in that: In step five, the frost ice growth characteristics include the droplet condensation and freezing time, the frost branch growth start time, the frost layer thickness dynamic change curve, the dynamic frost rate curve, the frost layer surface roughness and the frost layer surface inversion melting characteristic parameters.

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