A kind of tooling and method for testing heat transfer performance of temperature averaging plate

Abstract

This invention discloses a testing fixture and method for the heat transfer performance of a vapor chamber. The testing fixture includes a testing jig, an upper cooling plate, a lower cooling plate, a fan assembly, a heating resistor, a first thermocouple, and a second thermocouple. The testing jig includes a first clamp component and a second clamp component. The vapor chamber under test is fixed between the first clamp component and the second clamp component. The upper and lower cooling plates are respectively fixed at the top and bottom of the first and second clamp components. The fan assembly is fixed to the upper cooling plate. The heating resistor is installed at the center of the vapor chamber under test. The first thermocouple is fixed at the center of the heating resistor, and the second thermocouple is fixed at the middle of the ribs of the testing jig. This application designs a device suitable for testing structurally and functionally integrated vapor chambers manufactured through additive manufacturing in electronic devices, enabling the vapor chamber to operate under high power consumption and high heat flux density conditions, thus achieving the purpose of testing under liquid cooling and air cooling conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic equipment thermal management, and in particular to a temperature homogenizing plate heat transfer performance testing tool and a testing method. Background Art

[0002] With the rapid development of technology, the heat consumption and heat flux density of electronic equipment / electronic modules / electronic devices / batteries have gradually increased. In order to effectively control the heat transfer temperature difference between the heat source and the heat sink, a variety of materials or methods for enhancing heat transfer have been developed. The core purpose of these materials or methods is to significantly increase the characteristic thermal conductivity of the heat transfer structure to reduce the structural heat transfer temperature difference under high heat consumption and high heat flux conditions.

[0003] Circulating phase change heat transfer technology is a process in which a liquid working medium absorbs heat at the hot end and evaporates into a gaseous working medium. It is cooled at the cold end and releases heat to condense into a liquid working medium. The liquid working medium eventually flows back to the hot end through a capillary structure or gravity, achieving rapid diffusion and transfer of heat between the hot end and the cold end. The heat spreader uses low-pressure phase change heat transfer technology and consists of a sealed shell, a capillary layer attached to the shell, and a working medium. The liquid working medium is heated and vaporized at the heating part, and the gas rapidly expands to the entire cavity. The gas is liquefied at the cooling part, and the liquid returns to the heating part through the capillary wick. In this way, heat transfer is achieved. The structure of the capillary wick is one of the core technologies of the heat spreader. The structural forms of the wick are usually groove type, screen type, powder sintering type, etc. The common feature of the above forms is that the wick structure design is subject to the production process, and it is difficult to achieve a higher heat transfer capacity. The wick produced using additive manufacturing technology can achieve higher heat transfer capabilities and can be used in electronic equipment / electronic modules / electronic devices / battery cooling systems with higher heat consumption and greater heat flux density than ordinary vapor chambers.

[0004] The performance of the temperature spreader can be expressed by the characteristic thermal conductivity, which shows the actual heat conduction capacity of the temperature spreader. After the temperature spreader is produced, it needs to be thermally tested to obtain the characteristic thermal conductivity. For ordinary temperature spreaders, the test is generally carried out by loading a heat source in the middle, loading a cold source at both ends or on the back of the temperature spreader, and obtaining the temperature rise of the heat source. For additively manufactured temperature spreaders, due to their higher heat transfer capacity, the above test method is difficult to judge the advantages of the temperature spreader under high heat consumption conditions. A new thermal performance test device is needed to test the heat transfer characteristics of additively manufactured temperature spreaders. Summary of the invention

[0005] The main purpose of the present invention is to provide a heat transfer performance testing tool for a temperature equalizing plate, aiming to solve the technical problem that the current heat transfer performance testing method for a temperature equalizing plate is not applicable to a temperature equalizing plate manufactured by additive manufacturing.

[0006] To achieve the above object, the present invention provides a heat transfer performance test tool for a temperature homogenizing plate, comprising:

[0007] A test fixture, the test fixture comprising a first fixture component and a second fixture component arranged opposite to each other, the first fixture component and the second fixture component are provided with wedge-shaped locking strips on the outside, and the temperature equalizing plate to be tested is fixed between the first fixture component and the second fixture component;

[0008] An upper cold plate and a lower cold plate, wherein the upper cold plate and the lower cold plate are respectively fixedly disposed on the top and the bottom of the first fixture component and the second fixture component;

[0009] A fan assembly, wherein the fan assembly is fixedly disposed on the upper cold plate;

[0010] A heating resistor, a first thermocouple and a second thermocouple, wherein the heating resistor is installed at the center of the temperature averaging board to be tested, the first thermocouple is fixed at the center of the heating resistor, and the second thermocouple is fixed at the middle of the rib of the test fixture.

[0011] Optionally, the upper cold plate and the lower cold plate are respectively provided with a coolant flow channel and an air duct.

[0012] Optionally, the fan assembly includes a fan cover and a fan disposed on the fan cover.

[0013] Optionally, the upper cold plate and the lower cold plate are screwed to the test fixture.

[0014] Optionally, the fan assembly is screwed onto the upper cold plate.

[0015] Optionally, the tooling further includes a heat source pressing block, which is threadedly connected to the temperature averaging plate to be measured to fix the heating resistor.

[0016] In addition, in order to achieve the above-mentioned purpose, the present application also provides a method for testing the heat transfer performance of a temperature vapor chamber, which is used for the heat transfer performance testing tool of the temperature vapor chamber as described above, and the method comprises:

[0017] S1: Use a wedge-shaped locking strip to install the temperature equalizing board with the heating resistor and the first thermocouple in the test fixture, and fix the second thermocouple in the middle of the rib of the test fixture;

[0018] S2: Turn on the liquid cooling system to supply liquid to the test fixture;

[0019] S3: Connect the heating resistor to the DC power supply, heat the heating resistor and wait for the temperature data detected by the two thermocouples to stabilize, and record the data;

[0020] S4: Calculate the temperature difference between the first thermocouple and the second thermocouple, and calculate the characteristic thermal conductivity λ of the measured structural function integrated temperature plate through the temperature difference c ; Among them, λ c =q"·l w / ΔT, where q" is the heat flux density of the heating resistor, l w is the distance between the two thermocouple installation locations, and ΔT is the temperature difference between the two thermocouples.

[0021] Compared with the existing lattice structure, the present invention has the following beneficial effects:

[0022] 1) Improved testing efficiency

[0023] In the traditional test method, before each test, the liquid cooling tube needs to be pressed on both sides of the tested temperature equalizer. In the method of the present invention, each test only needs to install the tested temperature equalizer on the rib of the test fixture using a wedge-shaped locking strip, which is simple and convenient, and has high test efficiency.

[0024] 2) Close to the application scenario

[0025] In the traditional test method, the liquid cooling tube is in direct contact with the temperature averaging board under test, and the heat path is excellent, but there is a certain gap with the actual application scenario. In actual application, the cold end of the temperature averaging board is generally not in direct contact with the liquid cooling tube, but is conducted to the heat sink such as the liquid cooling tube through the heat transfer path such as the locking strip. Therefore, there is a conduction thermal resistance between the cold end of the temperature averaging board and the final heat sink. In this case, if the traditional test method is used to directly contact the temperature averaging board with the cold end, the problem of conduction thermal resistance will be avoided during the test process, resulting in a certain gap between the test effect and the actual effect. In the method of the present invention, the temperature averaging board under test is in contact with the ribs of the test fixture through the heat transfer path of the wedge-shaped locking strip, and then heat is transferred to the liquid cooling tube through the ribs, which completely simulates the actual application scenario. Its conduction thermal resistance is very close to the actual situation, and the real heat transfer characteristics of the temperature averaging board under test can be better reflected during the test process.

[0026] 3) Enriched heat sink types

[0027] In traditional testing methods, usually only liquid cooling tubes can be used as heat sinks for the tested vapor chamber. In the method of the present invention, fans can be used to force air as a heat sink. In some application scenarios, the vapor chamber does not have liquid cooling resources, and only forced air can be used as a heat sink. At this time, the heat transfer path of the heat source is: heat source-the surface of the vapor chamber in contact with the heat source-the surface of the vapor chamber in contact with the cooling air-forced air. This path is different from the liquid cooling condition: under liquid cooling conditions, the heat transfer performance of the vapor chamber is mainly reflected in the temperature difference between the heat source and the ribs of the test fixture; under air cooling conditions, the heat transfer performance of the vapor chamber is mainly reflected in the temperature difference between the heat source and the air-cooled heat dissipation surface of the vapor chamber. Therefore, the method of the present invention enriches the types of heat sinks, so that the heat transfer characteristics of the vapor chamber can be tested more comprehensively.

[0028] 4) Improved the maximum heat consumption and maximum heat flux density of the test

[0029] In the traditional test method, since it is necessary to use a relatively simple method to press the liquid cooling tube onto the temperature averaging plate to be tested, a small-diameter hose is generally used for testing, so the liquid supply flow rate is small and cannot meet the test requirements under high heat consumption conditions. In the method of the present invention, since the metal liquid cooling plate and the test fixture are integrated into a design, there is no need to clamp the cooling part, so a low-flow resistance liquid cooling plate suitable for a higher flow rate can be designed, which improves the maximum heat consumption and maximum heat flux density of the heat source on the temperature averaging plate to be tested, making it more suitable for the heat transfer characteristics test of the additively manufactured temperature averaging plate.

[0030] 5) Improved the reliability of the test system

[0031] In the method of the present invention, the cooling part has been pre-installed in the test fixture, the simplicity of the test system is improved, and there is no need to operate the components of the cooling system during the test, so the reliability is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is an overall schematic diagram of the heat transfer performance testing tool of the temperature equalizing plate of the present invention.

[0033] Figure 2 It is a cross-sectional schematic diagram of the upper cold plate.

[0034] Figure 3 It is the installation diagram of the measured temperature averaging board and heating resistor.

[0035] Figure 4 It is a schematic flow chart of a method for testing the heat transfer performance of a temperature equalizing plate of the present invention.

[0036] Description of the accompanying figures: 1-fan cover, 2-upper cold plate, 3-lower cold plate, 4-temperature averaging plate to be measured, 5-fan, 6-coolant flow channel, 7-air duct, 8-heating resistor, 9-heat source pressing block, 10-first thermocouple, 11-second thermocouple.

[0037] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0038] It should be understood that the specific embodiments described herein are only used to explain the invention, and are not used to limit the invention.

[0039] The following will be combined with the drawings in the embodiments of the invention to clearly and completely describe the technical solutions in the embodiments of the invention. Obviously, the described embodiments are only part of the embodiments of the invention, not all of the embodiments. Based on the embodiments in the invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the invention.

[0040] It should be noted that all directional indications in the embodiments of the invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0041] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that they can be implemented by ordinary technicians in the field. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection required by the invention.

[0042] It should be noted that, through additive manufacturing, the steam chamber of the heat spreader can be processed into a shape that best conforms to the principles of heat transfer (for example, in the LRM module, a special-shaped steam chamber can be processed and extended to the heat transfer ribs of the module), further reducing the heat transfer thermal resistance and forming a heat spreader with integrated structure and heat transfer functions. The structure and shape of the heat spreader with integrated structure and function are more complex than those of the traditional flat heat spreader, and the heat diffusion and heat transport paths are more complex. Therefore, its thermal characteristic parameters are also more complex, and are closely related to the constraints and boundary conditions such as the total heat transfer power, ambient temperature, secondary heat exchange method, secondary heat exchange capacity, installation and use method and orientation, and exhibit complex nonlinear characteristics. Therefore, it is necessary to simulate the actual working boundary and the real working environment, and even to test the electronic equipment, modules, and units containing the heat spreader with integrated structure and function as a whole, in order to accurately grasp its thermal characteristic parameters and obtain its actual working performance. Therefore, for the heat spreader with integrated structure and function, the heat transfer performance can be tested using tooling according to its characteristics.

[0043] Under the above working conditions, liquid cooling or air cooling is usually used as the final heat sink of the heat transfer system. The thermal performance test device for additive manufacturing heat spreader can adapt to both liquid cooling and air cooling, two mainstream forced cooling forms, and is suitable for thermal performance testing of additive manufacturing heat spreaders.

[0044] At present, in the relevant technical field, the existing heat transfer performance testing method of the temperature equalizer is not applicable to the temperature equalizer manufactured by additive manufacturing.

[0045] In order to solve this problem, various embodiments of the heat transfer performance test fixture and test method of the heat spreader of the present invention are proposed. The heat transfer performance test fixture of the heat spreader provided by the present invention is designed to be suitable for testing the structure-function integrated heat spreader of additive manufacturing in electronic equipment / electronic modules / electronic devices / battery systems, so that the heat spreader can work under high power consumption and high heat flux density conditions, so as to achieve the purpose of testing the structure-function integrated heat spreader of additive manufacturing under liquid cooling and air cooling conditions, and judge whether the heat transfer characteristics of the heat spreader meet the requirements through testing.

[0046] This embodiment provides a method for performing a test using a vapor chamber heat transfer performance test tool, which includes the following steps:

[0047] First, a fixture is designed to clamp the standard-sized structural and functional integrated temperature-maintaining plate with a wedge-shaped locking strip.

[0048] Second, a liquid cooling plate, a fan assembly and an air duct are designed in the fixture. When designing the air duct in the liquid cooling plate, care should be taken to avoid the liquid cooling flow channel so that the fixture can use both liquid cooling and air cooling.

[0049] Third, fix the heating resistor on the measured temperature averaging board, and fix the temperature sensor on the heating resistor.

[0050] Fourth, use a wedge-shaped locking strip to clamp the temperature equalizing board to be tested in the fixture, and fix the temperature sensor to the rib of the test fixture.

[0051] Fifth, provide cooling liquid to the liquid cooling plate of the test fixture (or turn on the fan on the top of the test fixture to provide cooling air).

[0052] Sixth, power the heating resistor and adjust the heating power by controlling the voltage. The heating power should be adjusted to the maximum heat transfer design value of the additive manufacturing temperature evaporator under test.

[0053] Seventh, record the temperature of the two thermocouples and calculate the temperature difference. The characteristic thermal conductivity λ of the measured temperature equalization plate is calculated by the temperature difference. c According to Fourier's law of heat conduction, the calculation formula is: c =q"·l w / ΔT, where q" is the heat flux density of the heating resistor, l w It is the distance between the two thermocouple installation locations (equivalent to half the width of the measured temperature equalization plate), and ΔT is the temperature difference between the two thermocouples.

[0054] In order to explain the present application more clearly, a specific example of the heat transfer performance test of the temperature homogenizing plate is provided below.

[0055] See also Figure 1 The present embodiment provides a tool for testing the heat transfer performance of a temperature equalizing plate. When designing and processing the cold plate of the test fixture, the fan 5 is installed in the fan cover 1 to form a fan assembly, the upper cold plate 2 and the lower cold plate 3 are screwed to the test fixture body, and the fan assembly is screwed to the upper cold plate 2 to form a complete test fixture.

[0056] Reference Figure 2 According to the standard LRM structure and function integrated module structure dimensions, the coolant flow channel 6 and the air duct 7 are designed; wherein, the coolant flow channel 6 and the air duct 7 cannot produce structural interference.

[0057] Reference Figure 3 , install the heating resistor 8 at the center position of the tested temperature equalizing plate 4, fix the first thermocouple 10 at the center position of the heating resistor 8, fix the second thermocouple 11 at the middle position of the test fixture rib, and connect the heating resistor 8 to the DC power supply.

[0058] After that, the resistor is screwed and fixed using the heat source pressing block 9. The heat source pressing block 9 should be processed with a low thermal conductivity material (such as polytetrafluoroethylene, etc.) to avoid heat conduction through the pressing block as much as possible.

[0059] Reference Figure 4 This embodiment provides a method for testing the heat transfer performance of a vapor chamber, which is used in the above vapor chamber heat transfer performance testing tool. The testing method includes the following steps:

[0060] S1: Use a wedge-shaped locking strip to install the temperature equalizing board with the heating resistor and the first thermocouple in the test fixture, and fix the second thermocouple in the middle of the rib of the test fixture;

[0061] S2: Turn on the liquid cooling system to supply liquid to the test fixture;

[0062] S3: Connect the heating resistor to the DC power supply, heat the heating resistor and wait for the temperature data detected by the two thermocouples to stabilize, and record the data;

[0063] S4: Calculate the temperature difference between the first thermocouple and the second thermocouple, and calculate the characteristic thermal conductivity λ of the measured structural function integrated temperature plate through the temperature difference c ; Among them, λ c =q"·l w / ΔT, where q" is the heat flux density of the heating resistor, l w is the distance between the two thermocouple installation locations, and ΔT is the temperature difference between the two thermocouples.

[0064] In this embodiment, a method for testing the thermal performance of an additively manufactured temperature vapor chamber is provided. By using the method provided in this application, the thermal characteristics of the additively manufactured temperature vapor chamber can be effectively tested (including thermal performance under different cooling heat sink conditions such as liquid cooling and air cooling, as well as thermal performance suitable for additively manufactured temperature vapor chambers such as high heat consumption and high heat flux density), providing a new solution.

[0065] In this embodiment, the comprehensive competitiveness of electronic equipment / electronic modules / electronic devices / batteries is also improved. In the process of developing temperature spreaders for additive manufacturing of electronic equipment / electronic modules / electronic devices / batteries, after applying the present invention, on the one hand, the test efficiency can be significantly improved, thereby reducing the test cost, and on the other hand, thermal performance data that is more suitable for temperature spreaders for additive manufacturing can be obtained through testing, and the thermal performance parameters of the temperature spreaders under various cooling methods can also be obtained, which effectively promotes the application of temperature spreaders for additive manufacturing in various cooling scenario products, thereby improving the comprehensive competitiveness of the products.

[0066] The above are only preferred embodiments of the invention, and are not intended to limit the patent scope of the invention. Any equivalent structure or equivalent process transformation made using the contents of the invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the invention.

Claims

1. A tool for testing the heat transfer performance of a temperature equalizing plate, characterized in that: include: A test fixture, the test fixture comprising a first fixture component and a second fixture component which are arranged opposite to each other, the first fixture component and the second fixture component are provided with wedge-shaped locking strips on the outside, and the temperature equalizing plate (4) to be tested is fixed between the first fixture component and the second fixture component; An upper cold plate (2) and a lower cold plate (3), wherein the upper cold plate (2) and the lower cold plate (3) are respectively fixedly arranged on the top and the bottom of the first fixture component and the second fixture component; A fan assembly, the fan assembly being fixedly arranged on the upper cold plate (2); A heating resistor (8), a first thermocouple (10) and a second thermocouple (11), wherein the heating resistor is installed at the center position of the temperature averaging plate (4) to be tested, the first thermocouple (10) is fixed at the center position of the heating resistor (8), and the second thermocouple (11) is fixed at the middle position of the rib of the test fixture; The upper cold plate (2) and the lower cold plate (3) are respectively provided with a coolant flow channel (6) and an air duct (7); the coolant flow channel (6) and the air duct (7) cannot cause structural interference; The tooling also includes a heat source pressing block (9), which is threadedly connected to the measured temperature averaging plate (4) to fix the heating resistor (8).

2. The heat transfer performance testing tool for a temperature homogenizing plate according to claim 1, characterized in that: The fan assembly comprises a fan cover (1) and a fan (5) arranged on the fan cover (1).

3. The heat transfer performance testing tool for a temperature homogenizing plate according to claim 1, characterized in that: The upper cold plate (2) and the lower cold plate (3) are screwed onto the test fixture.

4. The heat transfer performance testing tool for a temperature homogenizing plate according to claim 1, characterized in that: The fan assembly is screwed onto the upper cold plate (2).

5. A method for testing the heat transfer performance of a temperature equalizing plate, characterized in that: A tool for testing heat transfer performance of a temperature homogenizing plate according to any one of claims 1 to 4, the method comprising: S1: Use a wedge-shaped locking strip to install the temperature equalizing board with the heating resistor and the first thermocouple in the test fixture, and fix the second thermocouple in the middle of the rib of the test fixture; S2: Turn on the liquid cooling system to supply liquid to the test fixture; S3: Connect the heating resistor to the DC power supply, heat the heating resistor and wait for the temperature data detected by the two thermocouples to stabilize, and record the data; S4: Calculate the temperature difference between the first thermocouple and the second thermocouple, and calculate the characteristic thermal conductivity λ of the measured structural function integrated temperature plate through the temperature difference c ;in, in, is the heat flux density of the heating resistor, l w is the distance between the two thermocouple installation locations, and ΔT is the temperature difference between the two thermocouples.

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