Device for realizing melting-solidification circulation experiment of phase-change material

Abstract

The invention belongs to the field of material engineering, and particularly relates to a device for realizing a phase change material melting-solidification circulation experiment, which comprises a base, a rotating assembly, a lifting assembly, a telescopic assembly and an electric control assembly. The rotating assembly is installed at the top of the base, the lifting assembly is installed at the top of the rotating assembly, the telescopic assembly is transversely installed at the side end of the lifting assembly, and the base, the rotating assembly, the lifting assembly and the telescopic assembly form an L-shaped space structure. By arranging a steering engine in the rotating assembly, a stepping motor and a linear lead screw sliding table in the lifting assembly and a single-chip microcomputer in the electric control assembly, complex motion logic containing three degrees of freedom is achieved. A thermocouple is placed on a container support to collect temperature data in real time, the temperature data are compared with the melting point of the phase change material, and whether the material is completely melted or solidified in the cycle test process is judged. The device can be used for the circulation test of melting and solidification of the phase-change material in a laboratory, and the efficiency of the circulation test of the phase-change material is improved.

Description

Technical Field

[0001] The invention belongs to the field of material engineering, and in particular relates to a device for realizing a melting-solidification cycle experiment of a phase change material. Background Art

[0002] Phase change materials (PCMs) are a class of specialized materials that can undergo phase transitions (such as solid-liquid phase transitions) under constant temperature conditions, absorbing or releasing large amounts of latent heat. They are widely used in energy storage and temperature control. The melting-solidification cycle performance of PCMs directly determines their overall functionality and service life. However, existing devices for implementing PCM melting-solidification cycles typically use a single motor or complex transmission structures to achieve two degrees of freedom of motion. This presents the following drawbacks: First, the mechanical structure is complex; second, single-motor controlled devices struggle to implement complex motion logic, resulting in insufficient flexibility; third, the containers holding PCMs are often homogeneous structures with high thermal resistance, significantly extending the time required for a single cycle; and fourth, the parameters of the heating and solidification processes are typically fixed and cannot be adjusted in real time to meet actual needs. This not only reduces efficiency but may also result in incomplete melting or solidification of the PCM. Therefore, developing an automated device capable of independently performing the melting and solidification cycles of PCMs is of great significance for implementing PCM melting-solidification cycle experiments. Summary of the Invention

[0003] The purpose of the present invention is to provide a device for realizing a phase change material melting-solidification cycle experiment, so as to realize the functions of phase change material cyclic melting and solidification in a laboratory and improve the efficiency of phase change material cyclic testing.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A device for implementing a phase change material melting-solidification cycle experiment comprises: a base, a rotating assembly, a lifting assembly, a telescopic assembly, and an electronic control assembly; the rotating assembly is mounted on top of the base, the lifting assembly is mounted on top of the rotating assembly, and the telescopic assembly is mounted laterally on the side of the lifting assembly; the base, rotating assembly, lifting assembly, and telescopic assembly form an "L"-shaped spatial structure;

[0006] The rotating assembly includes a turntable and a rotating platform; the turntable is mounted on the base, the rotating platform is mounted on the turntable, a steering gear is installed between the two, the steering gear body is fixed to the turntable, the output shaft is connected to the rotating platform through a flange, and the rotating platform is driven by the steering gear to rotate along a vertical axis perpendicular to the turntable;

[0007] The lifting assembly includes a stepper motor bracket, a stepper motor and a linear screw slide; the stepper motor bracket is fixed to the rotating platform; the stepper motor is fixedly mounted on the stepper motor bracket, and its output shaft is coaxially connected to the linear screw slide; under the drive of the stepper motor, the linear screw slide can perform reciprocating linear motion in the vertical direction;

[0008] The telescopic assembly includes a guide shaft bracket, a sleeve, a single-head external threaded cylindrical pin and a telescopic rod; the guide shaft bracket is fixed on the linear screw slide; the sleeve is fixedly connected to the guide shaft bracket; one end of the telescopic rod and the sleeve are assembled with a clearance fit, and the radial fixation of the two is achieved by the single-head external threaded cylindrical pin; a bracket for fixing the phase change material container is installed at the other end, and a threaded hole is provided on the telescopic rod; the single-head external threaded cylindrical pin is screwed into the threaded hole of the telescopic rod, and its end abuts the inner wall of the sleeve to achieve locking; the container bracket is perpendicular to the telescopic direction, and a clamp is installed on the end of the container bracket close to the telescopic rod, and a container is installed on the end away from the telescopic rod;

[0009] The thermocouple is fixed to the container holder by a clamp, and its working end is placed in the container;

[0010] When length adjustment is required, first loosen the single-head external thread cylindrical pin and rotate it 90° to release the radial constraint, then slide the telescopic rod axially to the desired position, and then rotate the single-head external thread cylindrical pin 90° in the opposite direction and lock it; when sampling is required and the phase change material is kept in a molten state, loosen the single-head external thread cylindrical pin and then rotate it by a set angle to release the constraint.

[0011] Furthermore, the above-mentioned device for realizing the phase change material melting-solidification cycle experiment also includes an electronic control component, which is composed of a fixed plate, a single-machine chip, a stepper motor driver, a breadboard and a host computer. The single-machine chip, the stepper motor driver and the breadboard are all arranged on the fixed plate. The single-machine chip is connected to the servo, the host computer and the stepper motor driver respectively through the breadboard, and the stepper motor driver is connected to the stepper motor.

[0012] Furthermore, the container bracket is fixed to the telescopic rod by screws, and a clamp for clamping the thermocouple is installed at one end of the container bracket close to the telescopic rod, and a phase change material container is installed at one end away from the telescopic rod.

[0013] Furthermore, the base and the stepper motor bracket are both countersunk to avoid interference between the bolt heads and the rotating assembly or the lifting assembly during installation.

[0014] Furthermore, the base and the turntable are connected by bolts, and a gasket is provided between the two to protect the turntable surface.

[0015] Furthermore, the required rotation angle range of the single-head external thread cylindrical pin is 0-180°. By rotating the angle of the single-head external thread cylindrical pin, the container connected to the telescopic rod is driven to rotate, thereby realizing convenient collection of samples during the circulation process.

[0016] Furthermore, in order to shorten the time of the device's back-and-forth displacement and make the phase change material melt more fully through the displacement of the spiral, the motion trajectory of the container after rising 10 cm is synthesized by the vectors of the rotating part and the lifting part, forming a motion trajectory of "rise 10 cm → rise and rotate → fall → rise 10 cm → rise and rotate → fall..."

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The present invention realizes complex motion logic with three degrees of freedom by setting a servo in the rotating component, a stepping motor and a linear screw slide in the lifting component, and a single chip in the electronic control component, thereby improving the flexibility of the device.

[0019] 2. This invention uses thermocouples placed on the container holder to collect real-time temperature data, compare it with the melting point of the phase-change material, and then uses a host computer to determine whether the phase-change material has completely melted or solidified during the cycle. This can be used to implement cyclic melting and solidification functions for phase-change materials in the laboratory, improving the efficiency of phase-change material cyclic testing.

[0020] 3. Since the present invention adopts a servo and a stepper motor for control, and integrates a single-chip microcomputer in the electronic control component, it is possible to control the rotation angle of the servo and the lifting height of the stepper motor through programming, and ultimately obtain the precise position of the phase change material container. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0022] Figure 2 This is an exploded diagram of the rotating component;

[0023] Figure 3 Schematic diagram of the container structure;

[0024] Figure 4 This is a schematic diagram of the stepper motor support;

[0025] Figure 5 Schematic diagram of the thermocouple fixture structure;

[0026] Figure 6 Schematic diagram of the telescopic bracket structure;

[0027] Figure 7 Run the process logic diagram for the device;

[0028] Reference numerals:

[0029] 101 is the base; 102 is the turntable; 103 is the rotating platform; 104 is the servo bracket; 105 is the servo; 106 is the flange; 201 is the stepper motor bracket; 202 is the linear screw slide; 203 is the guide shaft bracket; 204 is the sleeve; 205 is the single-head external threaded cylindrical pin; 206 is the telescopic rod; 207 is the container bracket; 208 is the thermocouple fixture; 209 is the thermocouple; 210 is the container; 301 is the fixing plate; 302 is the single-chip microcomputer; 303 is the stepper motor driver; 304 is the breadboard. DETAILED DESCRIPTION

[0030] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings and embodiments to provide a clear and complete description of the technical solution of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all 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.

[0031] like Figures 1-6 As shown, this embodiment provides a device for realizing a phase change material melting-solidification cycle experiment, comprising: a base, a rotating assembly, a lifting assembly, a telescopic assembly, an electronic control assembly and a thermocouple 209; the rotating assembly is installed on the top of the base 101, the lifting assembly is installed on the top of the rotating assembly, and the telescopic assembly is installed laterally on the side end of the lifting assembly, and the base, the rotating assembly, the lifting assembly and the telescopic assembly form an "L"-shaped spatial structure.

[0032] The rotating assembly includes a turntable 102 and a rotating platform 103. The turntable 102 is mounted on a base 101, and the rotating platform 103 is mounted on the turntable 102. A servo 105 is positioned between the two. The servo 105 body is fixed to the turntable 102 via a servo bracket 104. The output shaft is connected to the rotating platform 103 via a flange 106. The servo 101 drives the rotating platform to rotate horizontally relative to the turntable 102. To ensure stable operation of the entire device, in this embodiment, the base 101 and the rotating platform 103 are both formed by turning and drilling aluminum alloy. The maximum load of the turntable 102 is 80 kg. The base 101 is connected to the outer side of the turntable 102 by four bolts, with a gasket installed between the two to protect the turntable surface. The countersunk holes in the base 101 ensure a flat surface. The inner side of the turntable 102 is fixed to the rotating platform 103 with four bolts. The servo bracket 104 is installed on the base 101 with four bolts. The servo 105 is fixed to the servo bracket 104 with four bolts. The flange 106 on its output shaft (maximum torque of 60N·m) is connected to the servo shaft with eight screws and is rigidly fixed to the rotating platform 103 with eight screws. When the servo 105 rotates, it drives the flange 106 to drive the rotating platform to rotate. At this time, the turntable 102 and the rotating platform 103 rotate synchronously, while the base 101 remains fixed.

[0033] The lifting assembly comprises a stepper motor bracket 201, a stepper motor, and a linear guide slide 202. The stepper motor bracket 201 is 3D-printed from ABS material and secured to the rotating platform 103 via four screws. The stepper motor is fixed to the bracket, with its output shaft coaxially connected to the linear guide slide. Driven by the stepper motor, the linear guide slide performs reciprocating vertical linear motion. In this embodiment, the linear guide slide 202 has a maximum travel of 120 mm.

[0034] The telescopic assembly includes a guide shaft support 203, a sleeve 204, a single-ended externally threaded cylindrical pin 205, and a telescopic rod 206. One end of the guide shaft support 203 is fixed to the linear screw slide 202; one end of the sleeve 204 is fixedly connected to the other end of the guide shaft support 203. One end of the telescopic rod 206 and the other end of the sleeve 204 are assembled with a clearance fit, and the single-ended externally threaded cylindrical pin 205 radially secures the two. The other end of the telescopic rod 206 is provided with a container support 207 for securing a container 210. The telescopic rod 206 is provided with a threaded hole. The single-ended externally threaded cylindrical pin 205 screws into the threaded hole of the telescopic rod 206, and its end abuts against the inner wall of the sleeve to form a locking mechanism. The container support 207 is perpendicular to the telescopic direction of the telescopic rod 206. A clamp 208 is fixed to the end of the container support 207 closest to the telescopic rod 206, while the container 210 is mounted on the end away from the telescopic rod 206. The thermocouple 209 is fixed to the container holder 207 via a clamp 208 , and its working end is placed in the container 210 .

[0035] To adjust the length of telescopic bracket 206, first loosen single-ended externally threaded cylindrical pin 205 and rotate it 90° to release the radial constraint. Then, by moving single-ended externally threaded cylindrical pin 205 back and forth, axially slide telescopic rod 206 to the desired length. Then, rotate the single-ended externally threaded cylindrical pin 205 90° in the opposite direction and tighten it. To sample and maintain the phase-change material in a molten state, loosen single-ended externally threaded cylindrical pin 205 and rotate it again to the desired angle to release the constraint. Finally, pour the phase-change material from container 210 into an external collector.

[0036] In this embodiment, the container holder 207 is fabricated from sheet metal, one end of which is secured to the telescopic rod 206 by two screws. The container 210 is constructed of an anodized aluminum alloy and secured to the end of the container holder 207 away from the telescopic rod 206 by two screws. To improve thermal conductivity, the inner wall of the container incorporates multiple rectangular tabs. The thermocouple fixture 208 is 3D-printed from ABS material and is removably secured to the container holder 207 using a combination of bolts and nuts. Both the container 210 and the thermocouple 209 are constructed from stainless steel. The thermocouple 209 has a temperature measurement range of 0-400°C.

[0037] The electronic control assembly consists of a fixed plate 301, a single chip 302, a stepper motor driver 303, and a breadboard 304. The single chip 302, the stepper motor driver 303, and the breadboard 304 are all arranged on the fixed plate 301. The single chip 302 is connected to the servo 105, the host computer, and the stepper motor driver 303 via the breadboard 304. The stepper motor driver 303 is connected to the stepper motor. The fixed plate 301 is connected to the base. The single chip 302 receives various instructions from the host computer and controls the rotation angle of the servo 105 according to the instructions. In this embodiment, the servo 105 is powered by 6-8V DC, and the stepper motor is powered by 24-50V DC. After the data measured by the thermocouple 204 is read by the host computer through a card reader for temperature determination, a transmission instruction is generated to control the heating and solidification time of the phase change material.

[0038] The working process of the device for the above phase change material melting-solidification cycle experiment is as follows: Figure 7 As shown: Input parameter instructions into the host computer according to the requirements and transmit the parameter instructions to the single chip microcomputer 302. The parameter instructions include the starting position, ending position, rotation speed, number of cycles N, melting point T of the phase change material, and the rotation speed of the servo 105. melt And the stepper motor descends the height.

[0039] During the heating and melting stage:

[0040] After receiving the descent height command from the stepper motor, microcontroller 302 controls the stepper motor to descend, partially immersing the container in the high-temperature water bath. Thermocouple 209 then measures the temperature and feeds it back to the host computer. The host computer compares the feedback temperature with the melting point of the phase change material to determine whether it is completely melted. If the feedback temperature from the thermocouple is 2°C higher than the melting point, the material is considered completely melted.

[0041] During the cooling and solidification stage:

[0042] The host computer inputs the stepper motor's ascending parameters to control the stepper motor's ascending motion. Simultaneously, the servo 105 is rotated to the low-temperature water bath position. Next, the host computer inputs the stepper motor's descending parameters to control it to descend to the specified position. The thermocouple measures the temperature again and transmits feedback to the host computer. The host computer compares the feedback temperature with the phase change material's melting point to determine whether the material is completely solidified. When the thermocouple feedback temperature is 2°C below the melting point, the material is considered completely solidified.

[0043] The loop control logic of this implementation is:

[0044] After the material is completely solidified, the stepper motor is controlled to rise, and the servo rotates back to the heating position at the same time. At this point, a complete cycle is completed, the number of cycles is automatically increased by 1, and the next cycle begins until all the set number of cycles are completed.

[0045] To better demonstrate the usage and advantages of this invention patent, we take paraffin wax with a phase transition temperature of 44°C as an example. The detailed process is as follows:

[0046] (1) The temperature of the high-temperature water bath was set to 80°C, and the temperature of the low-temperature water bath was set to 20°C. The liquid levels of the high-temperature water bath and the low-temperature water bath were kept approximately the same. To ensure the constant temperature of the low-temperature water bath, a copper container was used to hold 1.5 L of water, and an axial flow fan was used to dissipate heat from the container at a speed of 1000 rpm.

[0047] (2) Weigh approximately 1g of paraffin sample and place it in a container. Connect the host computer to the microcontroller 302, and use the dual-channel DC power supply to power the servo 105 and the stepper motor respectively. Open the serial port program of the host computer, enter the parameters such as the high-temperature water bath angle, low-temperature water bath angle, rotation speed, phase change material melting point, number of cycles, and descent height, and click the start button.

[0048] The servo 105 rotates from the initial angle to the high-temperature water bath angle, and the slide descends into the high-temperature water bath to start heating. The descending time is 10 seconds. According to the real-time temperature feedback measured by the thermocouple, the time to ensure that the paraffin is completely melted is 35 seconds. After complete melting, the slide rises to the initial height, and then rotates to the low-temperature water bath angle. The slide descends into the low-temperature water bath. According to the real-time temperature feedback measured by the thermocouple, the time to ensure that the paraffin is completely solidified is 45 seconds. After complete solidification, the slide rises to the initial height, and the servo rotates to the high-temperature water bath angle to complete one cycle. The total time is 130 seconds. If the cycle is repeated 100 times, the total time is 3.6 hours.

[0049] Although the present invention has been described above with reference to preferred embodiments, this is not intended to limit the present invention. Persons skilled in the art will readily appreciate that various modifications and variations may be made without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A device for realizing a phase change material melting-solidification cycle experiment, comprising: Base, rotating assembly, lifting assembly, telescopic assembly and electronic control assembly; The rotating assembly is installed on the top of the base, the lifting assembly is installed on the top of the rotating assembly, and the telescopic assembly is installed laterally on the side end of the lifting assembly. The base, rotating assembly, lifting assembly and telescopic assembly form an "L"-shaped spatial structure; the characteristics are: The rotating assembly includes a turntable and a rotating platform; the turntable is mounted on the base, the rotating platform is mounted on the turntable, a steering gear is installed between the two, the steering gear body is fixed to the turntable, the output shaft is connected to the rotating platform through a flange, and the rotating platform is driven by the steering gear to rotate along a vertical axis perpendicular to the turntable; The lifting assembly includes a stepper motor bracket, a stepper motor and a linear screw slide; the stepper motor bracket is fixed to the rotating platform; the stepper motor is fixedly mounted on the stepper motor bracket, and its output shaft is coaxially connected to the linear screw slide; under the drive of the stepper motor, the linear screw slide can perform reciprocating linear motion in the vertical direction; The telescopic assembly includes a guide shaft bracket, a sleeve, a single-head external threaded cylindrical pin and a telescopic rod; the guide shaft bracket is fixed on the linear screw slide; the sleeve is fixedly connected to the guide shaft bracket; one end of the telescopic rod and the sleeve are assembled with a clearance fit, and the radial fixation of the two is achieved by the single-head external threaded cylindrical pin; a bracket for fixing the phase change material container is installed at the other end, and a threaded hole is provided on the telescopic rod; the single-head external threaded cylindrical pin is screwed into the threaded hole of the telescopic rod, and its end abuts the inner wall of the sleeve to achieve locking; the container bracket is perpendicular to the telescopic direction, and a clamp is installed on the end of the container bracket close to the telescopic rod, and a container is installed on the end away from the telescopic rod; The thermocouple is fixed to the container holder by a clamp, and its working end is placed in the container; When length adjustment is required, first loosen the single-head external thread cylindrical pin and rotate it 90° to release the radial constraint. At this time, slide the telescopic rod axially to the desired position, then rotate the single-head external thread cylindrical pin 90° in the opposite direction and lock it. When sampling is required and the phase change material is kept in a molten state, loosen the single-head external thread cylindrical pin and then rotate it to the set angle to release the constraint.

2. The device for realizing a phase change material melting-solidification cycle experiment according to claim 1, characterized in that: The device also includes an electronic control component, which consists of a fixed plate, a single-chip, a stepper motor driver, a breadboard and a host computer. The single-chip, the stepper motor driver and the breadboard are all arranged on the fixed plate. The single-chip is connected to the servo, the host computer and the stepper motor driver respectively through the breadboard, and the stepper motor driver is connected to the stepper motor.

3. The device for realizing a phase change material melting-solidification cycle experiment according to claim 1, characterized in that: The container bracket is fixed to the telescopic rod by screws. A clamp for clamping a thermocouple is installed at one end of the container bracket close to the telescopic rod, and a phase change material container is installed at the other end away from the telescopic rod.

4. The device for realizing a phase change material melting-solidification cycle experiment according to claim 1, characterized in that: The base and the stepper motor bracket are both countersunk.

5. The device for realizing a phase change material melting-solidification cycle experiment according to claim 1, characterized in that: The base and the turntable are connected by bolts, and a gasket is provided between the two.

6. The device for realizing a phase change material melting-solidification cycle experiment according to claim 1, characterized in that: The required rotation angle range of the single-head external thread cylindrical pin is 0-180°. By rotating the single-head external thread cylindrical pin, the container connected to the telescopic rod is driven to rotate, thereby realizing convenient collection of samples during the circulation process.

7. The device for realizing a phase change material melting-solidification cycle experiment according to any one of claims 1 to 6, characterized in that: The motion trajectory of the container after rising 10 cm is synthesized by the vectors of the rotating part and the lifting part.

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