CN201252709Y - Heat pipe and phase-change material combined thermal control device - Google Patents

Abstract

The utility model discloses a thermal control device combined with a heat pipe and a phase change material, which comprises a heat sink structure with a phase change material encapsulated inside. Exchanged heat pipes with heat medium inside; the heat pipes of the thermal control device of the present invention are connected together by heat conduction with the heat sink structure encapsulated with phase change materials inside, and the heat generated by the chip is mainly transferred out by the heat pipes. When the heat pipe temperature rises and reaches the phase change temperature of the heat pipe medium, the phase change material in the heat sink begins to absorb heat and undergo a phase change. The temperature of the thermal control device and the chip will remain at the phase change temperature of the phase change material instead of continuing The temperature rises, so as to achieve the purpose of overheating protection for the chip and the heat pipe; when the power of the chip drops, the heat pipe will take away the heat generated by the chip and the heat stored in the phase change material at the same time, so that the phase change material There will be a phase transition again and return to normal.

Description

Thermal control device combined with heat pipe and phase change material

technical field

The utility model relates to the technical field of thermal control devices, in particular to a combined thermal control device of a heat pipe and a phase change material.

Background technique

With the rapid development of microelectronics technology, the total power density and calorific value of electronic components per unit volume have increased significantly, and it has been reported that more than 55% of electronic equipment failure forms are caused by excessive temperature, so the heat of electronic components Control design plays a pivotal role in the development of electronic components. At present, the relatively mature thermal control system has various heat sink radiators; such as fans, pumps, and various heat-conducting solids or liquids. In order to adapt to the development of electronic technology, high-efficiency thermal control technologies such as phase change cooling (heat pipes, phase change materials, etc.) have been produced.

A heat pipe is a heat conductor that utilizes phase change heat transfer with high efficiency. One end of the heat pipe is an evaporation section, and the other end is a condensation section. The tube contains a liquid that transfers a large amount of heat during evaporation and a liquid-absorbing wick (capillary suction) that brings the liquid back to the starting point during condensation. Due to the small heat transfer temperature difference and large heat transfer capacity, the heat pipe does not need to pump the heat transfer medium, so it has been widely used in the field of thermal control of electronic components. At present, there are two thermal control methods for heat pipes used in electronic components: 1. Direct heat pipe, that is, the heat pipe is directly connected to the chip. This method is very convenient for processing and installation, but this method cannot fully exert the powerful heat exchange capacity of the heat pipe; 2. The heat sink and the heat pipe are combined. The heat sink, heat sink and heat pipe composite type is to bond the heat pipe and heat sink together and install it on the chip, bend the heat insulating section of the heat pipe so that the condensation section of the heat pipe is located at the other end of the heat sink, and install a fan on the top. This form of heat pipe can increase the heat exchange area of the heat pipe, and is excellent in the thermal control of high-power chips, especially CPU chips, so it is widely used. However, the condensation section and the evaporation section are on the same heat sink, which will cause the temperature of the heat sink to be too high, thereby affecting the life of the heat pipe and the electronic chip and the heat exchange efficiency of the heat pipe. Moreover, relying on fans to enhance heat dissipation not only increases energy consumption, but once the fan fails, there is a risk of burning out the heat pipe and electronic chips.

Solid-liquid phase change materials have the advantages of small volume, high heat storage density and constant temperature release heat. When the solid phase change material absorbs heat, it becomes a liquid; when the power of the electronic component is reduced, the phase change material dissipates heat to the environment and returns to a solid state. Therefore, the phase change process of the phase change material can be used to absorb the heat generated by the electronic components operating within a certain period of time, thereby protecting the electronic components. Since the phase change material can maintain a constant temperature during the phase change process, the phase change material has a good application prospect in the thermal protection of electronic components. At present, phase change materials are used in thermal control systems mainly by encapsulating phase change materials inside heat sinks, but the biggest problem in thermal control systems with pure phase change materials is that after all phase change materials in the heat sink are melted, the system temperature will drop. Continue to rise, and then lose the protection function of electronic components.

Utility model content

The purpose of this utility model is to provide a heat sink and its phase change material which can conduct heat exchange with the heat pipe outside the heat sink, store heat by the phase change material and protect the heat pipe thermal control device combined with the heat pipe and phase change material.

The technical solution of the utility model is: a thermal control device combined with a heat pipe and a phase-change material, including a heat sink structure with a phase-change material encapsulated inside, and at least one heat sink structure connected to the inside or outside of the heat sink structure. The phase change material in the structure conducts heat exchange, and the heat pipe with heat medium inside.

The heat sink structure is fixed on the base, the evaporation section of the heat pipe is embedded in the base, and the condensation section of the heat pipe extends out of the base.

The base is a copper base.

The heat sink structure is a closed cavity heat sink structure, and vertical fins are arranged inside the cavity heat sink structure, and a phase change material filling cavity is formed between the inner wall of the cavity heat sink structure and each fin , the phase change material is filled in each phase change material filling cavity, and the top of each phase change material filling cavity leaves a space for the expansion and contraction of the phase change material.

The height of the phase change material filled in each filling cavity is 80% of the fin height.

The phase change temperature of the phase change material is 3-4°C higher than the phase change temperature of the medium in the heat pipe.

The heat pipe of the thermal control device of the utility model is thermally connected with the heat sink structure with the phase change material packaged inside. Taking CPU heat dissipation as an example, the phase change material in the utility model is a solid-liquid phase change material. When the chip starts When the power of the chip suddenly increases or the heat pipe fails for some reason, the temperature of the heat sink and the heat pipe will rise further and reach the phase change temperature of the heat pipe medium, and the phase change in the heat sink will The material starts to absorb heat and melts in phase change, the temperature of the thermal control device and the chip will be maintained at the phase change temperature of the phase change material, and will not continue to heat up, so as to achieve the purpose of overheating protection for the chip and heat pipe; when the power of the chip drops , while the heat pipe takes away the heat generated by the chip, it will also take away the heat stored in the phase change material, so that the phase change material will solidify again and return to a solid state.

In addition, the evaporation section of the heat pipe of the present invention is buried inside the base, the condensation section is located outside the base, the cavity heat sink structure is fixed on the upper part of the base, and the base can choose a copper base with good thermal conductivity, so that the thermal control The overall structure of the device is solid and the heat exchange efficiency is high.

In addition, the phase change material of the utility model is filled in the cavity in the closed heat sink, and the top of the cavity where the phase change material is located has a phase change expansion space reserved for expansion and expansion when the phase change material absorbs heat and releases heat. Shrinkage, the phase change temperature of the phase change material used is 3-4°C higher than the phase change temperature of the medium inside the heat pipe, so that the phase change material can achieve overheating protection within a certain temperature range.

Compared with the existing technologies such as heat pipe heat sink and heat sink with internal sealing phase change material, the utility model combines phase change material, heat sink and heat pipe to form a joint heating system of heat pipe and phase change material . The thermal protection of electronic components is achieved by using the constant temperature characteristics of phase change materials and the high-efficiency heat conduction capacity of heat pipes. While the heat pipes conduct heat efficiently, the phase change materials also provide thermal protection for heat pipes, thereby prolonging the service life of heat pipes. Using the utility model can control the working temperature of the electronic components below a certain temperature point, and has high heat exchange efficiency and stability. Therefore, the external fan can be eliminated, and the noise and vibration of the fan can be fundamentally eliminated. Component performance impact. In addition, the heat pipe in the utility model can also share a condensing section with other heat pipes in the electronic device, such as sharing a condensing section with the heat pipes for cooling the CPU chip, the north-south bridge chip, the graphics card chip, and the electronic devices in the power supply, so that the system The thermal control is further optimized to achieve the purpose of saving the overall cost.

Description of drawings

Fig. 1 is a structural representation of the utility model;

Fig. 2 is the BB sectional view of Fig. 1;

Fig. 3 is a sectional view taken along line A-A of Fig. 1 .

Detailed ways

As shown in Fig. 1, Fig. 2 and Fig. 3, the combined thermal control device of the present invention includes a copper base 6, and two heat pipes 5 with heat medium are fixed inside the base 6, and the two heat pipes 5 One end protrudes from the inside of the base 6 , wherein the evaporation section of the heat pipe 5 is buried inside the base 6 , and the condensation section is located outside the base 6 . A closed cavity heat sink structure 1 is fixedly attached to the upper surface of the base 6. The material of the cavity heat sink structure 1 is aluminum, and vertical aluminum fins are arranged inside the cavity heat sink structure 1. 4. A phase change material filling cavity is formed between the inner wall of the cavity heat sink structure 1 and each fin 4. The phase change material filling cavity is filled with a solid-liquid phase change material 3, and the top of each phase change material filling cavity 6 is uniform. There is space 2 for the expansion and contraction of the phase change material 3. The height of the phase change material filled in each filling cavity is 80% of the height of the ribs 4. The phase change temperature of the phase change material 3 requires a higher temperature than that of the medium in the heat pipe 5. The phase transition temperature is 3-4°C higher, and has a higher phase transition latent heat.

The heat pipe 5 in the above embodiments can also be arranged on the side or middle of the heat sink.

Claims (5)

1. A heat control device combined with a heat pipe and a phase-change material, characterized in that it includes a heat sink structure with a phase-change material encapsulated inside, and at least one wire connected to the inside or outside of the heat sink structure can be connected to the heat sink structure. A heat pipe with a heat medium inside for heat exchange using a phase change material. 2. The combined thermal control device of heat pipe and phase change material according to claim 1, characterized in that: the heat sink structure is fixed on the base, the evaporation section of the heat pipe is buried in the base, and the condensation section of the heat pipe protrudes outside the base. 3. The combined thermal control device of heat pipe and phase change material according to claim 2, wherein the base is made of copper. 4. The combined thermal control device of heat pipe and phase change material according to claim 1, 2 or 3, characterized in that: the heat sink structure is a closed cavity heat sink structure, and inside the cavity heat sink structure Vertical fins are provided, and a phase change material filling cavity is formed between the inner wall of the cavity heat sink structure and each fin, and the phase change material is filled in each phase change material filling cavity, and each phase change material filling cavity There is a space on the top to accommodate the expansion and contraction of the phase change material. 5. The combined thermal control device of heat pipe and phase change material according to claim 4, characterized in that: the height of the phase change material filled in each filling cavity is 80% of the height of the fins.

Images