CN105737432A - Thermoelectric refrigerator for loop heat pipe - Google Patents

Abstract

The invention relates to a thermoelectric refrigerator for loop heat pipes. The invention belongs to the field of thermoelectric technology. A thermoelectric refrigerator for a loop heat pipe, which is characterized in that: the thermoelectric refrigerator for a loop heat pipe includes a hot-side ceramic sheet, a cold-side ceramic sheet, a P-type thermoelectric element, an N-type thermoelectric element, and a flow guide The thermoelectric refrigerator has a square structure, the square structure hot surface ceramic sheet and the square structure cold surface ceramic sheet have a solder layer treated by immersion tin surface treatment, the square structure hot surface ceramic sheet and the square structure There are 71 pairs of P-type thermoelectric elements and N-type thermoelectric elements evenly arranged between the cold-faced ceramic sheets. The P-type thermoelectric elements and N-type thermoelectric elements are connected in series by the deflectors in sequence, leading to positive and negative wires. The invention has the characteristics of small size, high power, high heat flux density, etc., is suitable for starting the loop heat pipe, effectively ensures the normal and effective thermal driving of the loop heat pipe, and maintains the normal operation of the loop heat pipe.

Description

Thermoelectric cooler for loop heat pipe

technical field

The invention belongs to the field of thermoelectric technology, in particular to a thermoelectric refrigerator for a loop heat pipe.

Background technique

At present, with the rapid development of science and technology, many electronic products have a trend of miniaturization and refinement, but the performance requirements are getting higher and higher, and the relative power used must be higher and higher. In this way, the heating density on the surface of electronic components will increase rapidly, and the corresponding heat treatment problems will become very acute. Such as computer CPU, VGA, north and south bridge chipset or communication component PA, etc. How to solve this kind of heat dissipation problem in a limited space and ensure the normal function of electronic products has become a key technical problem and commercial demand that needs to be solved urgently.

Loop Heat Pipe (Loop Heat Pipe) is a high-efficiency phase change heat transfer device. It is composed of evaporator, compensator, and condenser. It is connected into a loop through a gas-liquid transmission pipeline. Phase change heat transfer from heat source to heat sink. The loop heat pipe has the structural characteristics of separation of gas-liquid pipelines and integration of evaporator and compensator, which determines its heat transfer characteristics of small gas-liquid carrying resistance, fast and flexible start-up, multi-directional long-distance heat transfer, and has become an aviation heat pipe. The heat transfer element of choice for control systems is also playing an increasingly important role in cooling systems for ground electronics.

The heat transfer performance of the loop heat pipe consists of four key technical indicators, the minimum starting power, the maximum operating power, the stable operating temperature and the thermal resistance of the circuit. The cooler can effectively solve the problem of starting the heat pipe.

Contents of the invention

The invention provides a thermoelectric refrigerator for a loop heat pipe to solve the technical problems existing in the known technology.

The purpose of the present invention is to provide a loop that has the characteristics of small size, high power, high heat flux density, etc., is suitable for the start-up of the loop heat pipe, effectively ensures the normal and effective thermal drive of the loop heat pipe, and maintains the normal operation of the loop heat pipe Thermoelectric cooler for heat pipe.

The thermoelectric refrigerator for a loop heat pipe of the present invention is composed of a hot-surface ceramic sheet, a cold-surface ceramic sheet, a P-type thermoelectric element, an N-type thermoelectric element, a guide plate, a positive wire, and a negative wire.

The number of pairs of thermoelectric elements is 71; the geometric size of the thermoelectric elements is 1.05mmX1.05mmX2.0mm; the distance between the thermoelectric elements is 0.6mm. The ceramic sheet is a metallized pattern sintered by W-Mn alloy, and the geometric size of the ceramic sheet is (23.0±0.05)mmX(23.0±0.05)mmX(0.65±0.05)mm. The material of the deflector is T2Y2 copper plate, the purity is ≥99.90%, and the thickness is 0.3mm. The positive and negative leads of the refrigerator are AWG22 wires, which meet the overcurrent requirements;

The surge current detection technology is introduced for the first time, there is no surge phenomenon during the start-up process of the refrigerator, and there is no electronic impact on its upper-level DC-DC module.

The lead wire welding technology of non-disturbance welding is adopted to avoid stress introduction during the test process and improve welding reliability. The non-disturbance welding system consists of a bracket, a screw mechanism and a spring. The bracket of the non-disturbance welding system is made of stainless steel, which is processed by wire cutting and milling to ensure the strength and rigidity, while ensuring the parallelism of the bottom plate part of the bracket and the screw mechanism part and their perpendicularity to the side plate; the non-disturbance welding system The material of the screw mechanism is 6061 aluminum alloy, the flatness of the ground is less than 0.02mm, and the parallelism is ≤0.03mm; the material of the spring mechanism of the non-disturbance welding system is made of high-performance 60Si2CrVA alloy.

Thermoelectric cooler for loop heat pipe, maximum temperature difference ΔTmax: ≥68°C; maximum temperature difference voltage Umax: 8.2V±0.8V; maximum temperature difference current Imax: 3A±0.3A; maximum cooling power Qcmax: ≥14W.

The technical scheme adopted by the loop heat pipe thermoelectric refrigerator of the present invention is:

A thermoelectric refrigerator for a loop heat pipe, which is characterized in that: the thermoelectric refrigerator for a loop heat pipe includes a hot-side ceramic sheet, a cold-side ceramic sheet, a P-type thermoelectric element, an N-type thermoelectric element, and a flow guide The thermoelectric refrigerator has a square structure, the square structure hot surface ceramic sheet and the square structure cold surface ceramic sheet have a solder layer treated by immersion tin surface treatment, the square structure hot surface ceramic sheet and the square structure There are 71 pairs of P-type thermoelectric elements and N-type thermoelectric elements evenly arranged between the cold-faced ceramic sheets. The P-type thermoelectric elements and N-type thermoelectric elements are connected in series by the deflectors in sequence, leading to positive and negative wires.

The thermoelectric refrigerator for the loop heat pipe of the present invention can also adopt the following technical scheme:

The thermoelectric refrigerator for the loop heat pipe is characterized in that: the square structure hot surface ceramic sheet and the square structure cold surface ceramic sheet have strong consistency in thickness, and the thickness of the solder layer of the ceramic sheet after grinding is 0.15 ± 0.05 mm.

The thermoelectric refrigerator for the loop heat pipe is characterized in that the geometric dimensions of the square-structured hot-faced ceramic sheet and the square-shaped cold-faced ceramic sheet are 23.0±0.05mm, 23.0±0.05mm, and 0.65mm respectively. ±0.05mm.

The thermoelectric refrigerator for the loop heat pipe is characterized in that: the geometric dimensions of the P-type thermoelectric element and the N-type thermoelectric element are 1.05mmX1.05mmX2.0mm; the P-type thermoelectric element and the N-type thermoelectric element The pitch is 0.6mm.

The present invention has the following characteristics:

1. For the first time, the non-disturbance welding technology is introduced, and the lead wire and the pad are kept in an absolutely static state by designing a special lead wire welding tool, so as to avoid the existence of mechanical stress and improve reliability;

2. Use grinding technology to treat the surface of the ceramic chip after dipping in tin to obtain a surface with a strong consistency in the thickness of the solder layer. The thickness of the solder layer of the ceramic chip after grinding is controlled at 0.15±0.05mm;

3. For the first time, X-ray detection technology was introduced, and 100% inspection was carried out by X-ray detection technology on the polished ceramic sheet. The test results showed that the wettability of the welded area exceeded 95%, which was much higher than the requirement of the wetted area ≥ 75%;

4. The inrush current detection technology was introduced for the first time to detect the inrush current during the start-up process of the refrigerator and its influence on the power supply DC-DC module;

5. Adopt the high-efficiency working mode, and the maximum efficiency of the refrigerator supporting the loop heat pipe can reach more than 85%;

6. The refrigerator has excellent performance in durability, temperature environment and space radiation environment.

The advantages and positive effects that the present invention has are:

The thermoelectric refrigerator for loop heat pipe adopts the brand-new technical solution of the present invention. Compared with the prior art, the present invention has the following characteristics:

1. The brand-new thermoelectric refrigerator for loop heat pipes of the present invention has the characteristics of small size, high power, and high heat flux density, and is suitable for the start-up of loop heat pipes, effectively ensuring the normal and effective thermal driving of loop heat pipes , Keep the loop heat pipe running normally.

2. The thermoelectric cooler for the loop heat pipe can effectively solve the start-up tube technology of the loop heat pipe. It has laid a solid foundation for the industrialization and engineering of loop heat pipe space and ground military and civilian fields. It is of great significance to expand the application field of refrigerators to promote the development of thermoelectric technology.

Description of drawings

Fig. 1 is a structural schematic diagram of a thermoelectric cooler for a loop heat pipe;

In the figure, 1-hot surface ceramic sheet, 2-cold surface ceramic sheet, 3-P-type thermoelectric element, 4-N-type thermoelectric element, 5-flow deflector, 6-positive wire, 7-negative wire;

Fig. 2 is a top view structural diagram of the thermoelectric cooler for the loop heat pipe in Fig. 1;

Fig. 3 is a structural schematic diagram of a thermoelectric cooler without disturbance welding system for a loop heat pipe;

Fig. 4 is a top view structural diagram of the non-disturbance welding system of the thermoelectric cooler for the loop heat pipe in Fig. 3 .

In the figure, 8-thermoelectric refrigerator, 9-support, 10-screw mechanism, 11-spring.

detailed description

In order to further understand the invention content, characteristics and effects of the present invention, the following examples are given, and detailed descriptions are as follows in conjunction with the accompanying drawings:

Example 1

Refer to accompanying drawing 1, Fig. 2 Fig. 3 and Fig. 4.

A thermoelectric refrigerator for a loop heat pipe, comprising a hot-surface ceramic sheet, a cold-surface ceramic sheet, a P-type thermoelectric element, an N-type thermoelectric element, a deflector, a positive lead wire and a negative lead wire, and the thermoelectric refrigerator It is a square structure, the square structure hot surface ceramic sheet and the square structure cold surface ceramic sheet have a solder layer that has been dipped in tin, and there are 71 pairs of P-type ceramic sheets evenly arranged between the square structure hot surface ceramic sheet and the square structure cold surface ceramic sheet The thermoelectric element and the N-type thermoelectric element, the P-type thermoelectric element, and the N-type thermoelectric element are serially connected in series by the deflector, leading out the positive electrode wire and the negative electrode wire.

The surface of the square structure hot surface ceramic sheet and the square structure cold surface ceramic sheet have strong thickness consistency, and the thickness of the solder layer of the ceramic sheet after grinding is 0.15±0.05mm. The geometric dimensions of the square-structured hot-faced ceramic sheet and the square-shaped cold-faced ceramic sheet are 23.0±0.05mm, 23.0±0.05mm, and 0.65±0.05mm, respectively. The geometric size of the thermoelectric element is 1.05mmX1.05mmX2.0mm; the distance between the thermoelectric elements is 0.6mm.

During the preparation of this embodiment, the loop heat pipe uses a thermoelectric refrigerator, and the thickness of the tin layer of the ceramic sheet is treated by grinding technology to treat the surface of the ceramic sheet after soaking in tin, so as to obtain a surface with a strong consistency in the thickness of the solder layer. The thickness of the ceramic solder layer is controlled at 0.15±0.05mm.

The thermoelectric refrigerator for the loop heat pipe introduces X-ray detection technology, and conducts 100% inspection on the ceramic sheet after grinding. The test results show that the wettability of the welded area exceeds 95%, which is much higher than the wetted area. ≥75% requirement.

The loop heat pipe uses a thermoelectric cooler, and the surge current detection technology is introduced. There is no surge phenomenon during the start-up process of the cooler, and there is no electronic influence on the DC-DC module of its superior.

The non-disturbance welding system of a thermoelectric refrigerator for a loop heat pipe is composed of a bracket, a screw mechanism and a spring. The bracket provides a platform for welding, and a groove with a depth of 2.0mm is opened on the bottom plate according to the size of the refrigerator, and the groove width is 24.5mmX24.5mm, which is used to fix the semi-finished product of the refrigerator; the product of the refrigerator is compressed and fastened by a screw mechanism The power is provided by a spring with sufficient strength; the right side of the bottom plate is located at the outlet position of the lead wire (positive and negative pole positions), and a groove is opened to the right side, the groove depth is 1mm, the groove width is Φ1.2mm, the upper part of the groove and the diameter Consistent, open type; when there is no disturbance welding, put the prepared lead wire into the groove and fix it, then use an electric soldering iron to weld the solder joints of the lead wire. There is no relative movement of the lead wire, ceramic sheet, and welding system during the welding process. Ensure welding quality.

The thermoelectric refrigerator for the loop heat pipe in this embodiment has positive effects such as small size, high power, high heat flux density, excellent mechanical resistance, performance in temperature environment and space radiation environment. It is suitable for the start-up of the loop heat pipe, effectively ensuring the normal and effective thermal drive of the loop heat pipe and maintaining the normal operation of the loop heat pipe. It has laid a solid foundation for the industrialization and engineering of loop heat pipe space and ground military and civilian fields.

Claims (4)

1. A thermoelectric cooler for a loop heat pipe is characterized in that: the thermoelectric cooler for a loop heat pipe comprises a hot surface ceramic sheet, a cold surface ceramic sheet, a P-type thermoelectric element, an N-type thermoelectric element, The deflector, the positive lead wire and the negative lead wire, the thermoelectric cooler has a square structure, the square structure hot surface ceramic sheet and the square structure cold surface ceramic sheet have a solder layer treated by immersion tin surface treatment, the square structure hot surface ceramic sheet and There are 71 pairs of P-type thermoelectric elements and N-type thermoelectric elements evenly arranged between the square-shaped cold surface ceramic sheets. wire. 2. The thermoelectric cooler for loop heat pipe according to claim 1, characterized in that: the square structure hot surface ceramic sheet and the square structure cold surface ceramic sheet have a strong surface thickness consistency, and the ceramic sheet solder after grinding The layer thickness is 0.15±0.05mm. 3. The thermoelectric cooler for loop heat pipe according to claim 1, characterized in that: the geometric dimensions of the square-structured ceramic sheet on the hot surface and the square-structured cold-surface ceramic sheet are respectively 23.0 ± 0.05mm, 23.0 ± 0.05mm, 23.0±0.05mm, 0.65±0.05mm. 4. The thermoelectric cooler for loop heat pipe according to claim 1, characterized in that: the geometric dimensions of the P-type thermoelectric element and the N-type thermoelectric element are 1.05mmX1.05mmX2.0mm; the P-type thermoelectric element , N-type thermoelectric element spacing is 0.6mm.