CN113163672B

CN113163672B - Phase change heat storage type radiator utilizing thermal expansion of phase change material

Info

Publication number: CN113163672B
Application number: CN202110256092.XA
Authority: CN
Inventors: 丁斌; 冯文创; 巩亮; 方健
Original assignee: China University of Petroleum East China
Current assignee: China University of Petroleum East China
Priority date: 2021-03-09
Filing date: 2021-03-09
Publication date: 2022-06-07
Anticipated expiration: 2041-03-09
Also published as: CN113163672A

Abstract

The invention discloses a phase change heat storage type radiator utilizing the thermal expansibility of a phase change material, which comprises a top cover, a negative pressure region, a packaging base body, a composite channel pipe, an organic phase change material and a cold plate, wherein the cold plate is arranged at the bottom of the packaging base body; the high-temperature liquid phase-change material close to the bottom heat source is released to the top position by utilizing the high pressure generated by the thermal expansion of the phase-change material, so that the efficiency of phase-change energy storage can be effectively improved, the heat dissipation performance is improved, and the effective protection time of special electronic equipment such as missile-borne equipment is prolonged. And the serious consequence that the phase-change material cannot normally operate due to leakage of the phase-change material caused by the fact that the expansion volume is enlarged and the internal pressure is rapidly increased after the phase-change material is melted is effectively solved.

Description

Phase change heat storage type radiator utilizing thermal expansion of phase change material

Technical Field

The invention relates to the technical field of heat dissipation of electronic equipment, in particular to a phase change heat storage type heat radiator utilizing thermal expansibility of a phase change material.

Background

Along with the rapid development of society, electronic circuits become more complex, the operation load is continuously increased and the miniaturization is developed, the local heat flux density of equipment in the working process becomes larger and larger along with the improvement of integration level, and the heat dissipation problem is increasingly prominent. For the missile-borne electronic equipment, more heat can be released in a short time, if the heat dissipation can not be reasonably optimized, the temperature of an electronic device can be rapidly increased, certain damage is caused to a missile-borne system, and the normal operation of the missile-borne electronic equipment is seriously influenced. When the temperature exceeds a certain critical value, some electronic devices can completely fail, which has a great influence on the battle mission and even the national defense safety.

At present, the thermal design of missile-borne electronic equipment is mostly a passive heat dissipation technology of sensible heat energy storage or latent heat energy storage. Sensible heat energy storage rises through the temperature of missile-borne equipment self material and comes the stored energy, utilizes sensible heat energy storage technique to dispel the heat, and the material temperature constantly changes, and the energy storage density of material is lower, needs comparatively huge device during the use, receives the restriction of entire system weight and volume, and sensible heat energy storage heat dissipation technique can't satisfy electronic equipment's heat dissipation demand gradually. The phase-change material basically keeps the temperature unchanged in the phase-change process and can absorb a large amount of heat, so the phase-change energy-storage heat dissipation technology using the phase-change material has great attraction on solving the heat dissipation problem of the missile-borne electronic device. At present, phase change energy storage materials are mainly classified into gas-liquid phase change materials, solid-gas phase change materials and solid-liquid phase change materials according to phase change forms and phase change processes. Gas exists in the phase change process of gas-liquid phase change and solid-gas phase change, and the volume occupied by the gas is too large, so that the gas is less adopted in practical application. Solid-liquid phase transition is widely focused because it has advantages such as a much larger latent heat of vaporization than that of sensible heat, a low cost, and a wide phase transition temperature range, although much smaller than that of vaporization. The solid-liquid phase change material is divided into an organic phase change material and an inorganic phase change material, wherein the organic phase change material represented by paraffin has the advantages of large latent heat of fusion, low density, low cost, stable physicochemical property and wide melting point range, so the application is the most extensive. However, organic phase change materials such as paraffin have a relatively large thermal expansion coefficient near the melting point, and the volume of the organic phase change materials is rapidly increased in the phase change process, so that the internal pressure is rapidly increased, and finally the phase change materials are leaked. Most studies at present consider that the method is a big disadvantage in practical application.

Disclosure of Invention

The invention aims to provide a phase-change heat storage type radiator utilizing the thermal expansion property of a phase-change material, which is used for solving the problems in the prior art, and the high-temperature liquid phase-change material close to a bottom heat source is released to a specified position by utilizing the high pressure generated by the thermal expansion of the phase-change material, so that the phase-change energy storage efficiency can be effectively improved, the heat dissipation performance is improved, and the effective protection time of special electronic equipment such as missile-borne equipment is prolonged. And the serious consequence that the phase-change material cannot normally operate due to leakage of the phase-change material caused by the fact that the expansion volume is enlarged and the internal pressure is rapidly increased after the phase-change material is melted is effectively solved.

In order to achieve the purpose, the invention provides the following scheme:

the invention provides a phase change heat storage radiator utilizing the thermal expansion of a phase change material, which comprises a top cover, a negative pressure area, a packaging base body, a composite channel pipe, an organic phase change material and a cold plate, the top cover is arranged on the top of the packaging base body and is provided with a vacuum slot hole which is used for connecting a vacuum pump, the vacuum pump is used for pumping out air at the bottom of the top cover to form the negative pressure area, the cold plate is arranged at the bottom of the packaging base body, the packaging substrate is internally provided with a composite channel pipe which is enclosed by a heat conduction pipe and a heat insulation pipe, the heat conduction pipe is arranged on the inner layer of the heat insulation pipe, the packaging base body at the bottom of the negative pressure area is filled with the organic phase change material, the part of the bottom of the heat conduction pipe protruding out of the heat insulation pipe is fixed on the cold plate, and the heat conducting pipe of the part is axially provided with a cross groove, and the part of the top of the heat conducting pipe, which protrudes out of the heat insulation pipe, is positioned in the negative pressure area.

Preferably, the inner heat insulation pipe and the packaging base body are made of polytetrafluoroethylene materials.

Preferably, the heat conduction pipe and the cold plate are made of red copper materials, and the heat conduction pipe is welded on the cold plate.

Preferably, the cross groove is a cross groove hole formed on the bottom tube body of the heat conduction tube.

Preferably, the cold plate is in direct contact with the heat dissipation surface of the electronic device and is coated with a thermally conductive silicone grease.

Compared with the prior art, the invention has the following beneficial technical effects:

the phase change heat storage type radiator utilizing the thermal expansibility of the phase change material provided by the invention utilizes the thermal expansibility of the organic phase change material to convey the high-temperature liquid phase change material at the bottom of the heat exchanger to the top, thereby achieving the purposes of reducing the temperature at the bottom, dispersing heat to the top and simultaneously conducting heat transfer from the bottom and the top of the heat exchanger, and finally achieving the purposes of strengthening the performance of the heat exchanger and prolonging the effective protection time of electronic equipment. Meanwhile, the design scheme of the invention can effectively solve the problem of leakage of the phase-change material and improve the operation stability of the radiator. The solar heat-dissipating device has a very wide application prospect in the aspects of cooling of short-time heat-dissipating devices such as missile-borne electronic equipment and the like, solar heat storage and the like, and can be used as a standby heat-dissipating device when sudden conditions occur in active heat dissipation.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic perspective view illustrating a phase change thermal storage heat sink according to the present invention, which utilizes thermal expansion of a phase change material;

FIG. 2 is a partial enlarged view of a cross-shaped groove at the bottom A of the heat conductive pipe according to the present invention;

FIG. 3 is a top sectional view of a phase change thermal storage heat sink utilizing thermal expansion of a phase change material according to the present invention;

in the figure: 1-top cover, 2-vacuum slot, 3-negative pressure area, 4-packaging base body, 5-heat insulation pipe, 6-heat conduction pipe, 7-organic phase change material, 8-cross slot and 9-cold plate.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention aims to provide a phase change heat storage type heat radiator utilizing the thermal expansion property of a phase change material, so as to solve the problems in the prior art.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

The phase change heat storage type heat sink using thermal expansion of phase change material in this embodiment, as shown in fig. 1-3, includes a top cap 1, a negative pressure region 3, a packaging base 4, a composite channel tube, an organic phase change material 7, and a cold plate 9, where the top cap 1 is disposed on the top of the packaging base 4 and is provided with a vacuum slot 2, the vacuum slot 2 is used to connect a vacuum pump (not shown in the figure), the vacuum pump is used to pump out air at the bottom of the top cap 1 to form the negative pressure region 3, the cold plate 9 is disposed at the bottom of the packaging base 4, the packaging base 4 is provided with the composite channel tube surrounded by a heat pipe 6 and a heat insulation tube 5, the heat pipe 6 is disposed at an inner layer of the heat insulation tube 5, the packaging base 4 at the bottom of the negative pressure region 3 is filled with the organic phase change material 7, a portion of the heat pipe 6 protruding from the heat insulation tube 5 is fixed on the cold plate 9, and a cross groove is axially formed on the heat pipe 6 at this portion, the cross groove is a cross groove hole 8 formed on the bottom pipe body of the heat conduction pipe 6, and the cross groove hole 8 enables the phase change material to flow into the heat conduction pipe 6 from the cross groove upwards after being melted. The portion of the top of the heat pipe 6 protruding from the heat insulating pipe 5 is located in the negative pressure region 3.

In this embodiment, the inner insulating tube packaging substrate 4 is made of teflon; the heat conduction pipe 6 and the cold plate 9 are made of red copper materials, and the heat conduction pipe 6 is welded on the cold plate 9.

In this embodiment, the cold plate 9 is in direct contact with the heat dissipation surface of the electronic device and is coated with thermal grease to prevent a large thermal contact resistance. The arrangement position and the number of the composite channel pipes are designed according to the distribution and the size of the heat flux density, and the inner diameters and the wall thicknesses of the heat insulation pipes and the heat conduction pipes are designed according to the material properties and the heat flux density.

The working process of the invention is as follows:

the heat that electronic equipment produced transmits to cold drawing 9 through heat conduction silicone grease rapidly, because the red copper that heat pipe 6 used has higher coefficient of heat conduction, the heat can be passed through cold drawing 9 and upwards transmits along heat pipe 6 rapidly, because there is the heat insulating tube 5 that coefficient of heat conduction is lower outside the heat pipe 6, consequently the heat can only upwards reach the organic phase change material transmission in the passageway that heat pipe 6 enclosed, the organic phase change material in the passageway can melt fast, after the organic phase change material melts completely in the passageway, the heat exchanger bottom communicates with top negative pressure zone 3. Meanwhile, the organic phase change material in direct contact with the cold plate 9 is also melted, the organic phase change material is further melted along with the transfer and absorption of heat, the volume is increased after the melting, the internal pressure of the liquid phase change material at the bottom of the heat exchanger begins to increase, when the pressure difference between the internal pressure of the liquid phase change material at the bottom of the heat exchanger and the negative pressure zone 3 can overcome the gravity of the liquid phase change material, the liquid phase change material begins to flow to the negative pressure zone 3 along the composite channel through the cross-shaped slotted hole 8, when the liquid phase change material flows to the highest position of the heat conduction pipe 6, the high-temperature organic phase change material flows downwards to the bottom of the negative pressure zone 3 along the pipe wall, the flowing high-temperature fluid can transfer heat to the solid phase change material downwards, and the phase change material cannot be solidified to cause blockage at the outlet of the composite channel because no heat insulation pipe covers the top of the heat conduction pipe 6 of the negative pressure zone 3. Until the organic phase-change material is melted to be communicated with the negative pressure region 3, the phase-change material is melted basically and completely, and the heat storage is basically completed.

The principle and the implementation mode of the invention are explained by applying specific examples, and the description of the above examples is only used for helping understanding the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In summary, this summary should not be construed to limit the present invention.

Claims

1. A phase change heat storage type radiator utilizing thermal expansibility of a phase change material is characterized in that: comprises a top cover, a negative pressure region, a packaging matrix, a composite channel tube, an organic phase change material and a cold plate, wherein the top cover is arranged at the top of the packaging matrix and is provided with a vacuum slot hole, the vacuum slot is used for connecting a vacuum pump, the vacuum pump is used for pumping out air at the bottom of the top cover to form the negative pressure area, the cold plate is arranged at the bottom of the packaging base body, a composite channel pipe enclosed by a heat conduction pipe and a heat insulation pipe is arranged in the packaging base body, the heat conduction pipe is arranged on the inner layer of the heat insulation pipe, the packaging matrix at the bottom of the negative pressure area is filled with the organic phase change material, the part of the bottom of the heat conduction pipe, which protrudes out of the heat insulation pipe, is fixed on the cold plate, a cross groove is axially formed in the heat conduction pipe of the part, and the part, protruding out of the heat insulation pipe, of the top of the heat conduction pipe is located in the negative pressure area;

heat generated by the electronic equipment is transferred to the cold plate through the heat-conducting silicone grease, the heat is transferred upwards along the heat-conducting pipe through the cold plate, so that the organic phase-change material in the heat-conducting pipe is melted, and after the organic phase-change material in the heat-conducting pipe is completely melted, the bottom of the packaging base body is communicated with the negative pressure region at the top; meanwhile, the organic phase-change material in direct contact with the cold plate is also melted, the organic phase-change material is further melted along with the transfer and absorption of heat, the volume of the organic phase-change material is increased after the organic phase-change material is melted, the internal pressure of the liquid phase-change material at the bottom of the packaging substrate begins to increase, when the pressure difference between the internal pressure of the liquid phase-change material at the bottom of the packaging substrate and the negative pressure zone can overcome the gravity of the liquid phase-change material, the liquid phase-change material begins to flow to the negative pressure zone along the inside of the heat conduction pipe through the bottom of the heat conduction pipe, when the liquid phase-change material flows to the highest position of the heat conduction pipe, the liquid phase-change material flows downwards to the bottom of the negative pressure zone along the pipe wall of the heat insulation pipe, at the moment, the inflowing high-temperature fluid can transfer heat to the solid phase-change material downwards, no heat insulation pipe is arranged at the top of the negative pressure zone, and the liquid phase-change material cannot be solidified at the outlet of the composite channel pipe to cause blockage, until the organic phase change material melts into communication with the negative pressure zone.

2. The phase-change thermal storage heat sink using thermal expansion of a phase-change material according to claim 1, wherein: the heat insulation pipe and the packaging base body are made of polytetrafluoroethylene materials.

3. The phase-change thermal storage heat sink using thermal expansion of a phase-change material according to claim 1, wherein: the heat conduction pipe and the cold plate are made of red copper materials, and the heat conduction pipe is welded on the cold plate.

4. The phase-change thermal storage heat sink using thermal expansion of a phase-change material according to claim 1, wherein: the cross groove is a cross groove hole formed on the bottom pipe body of the heat conduction pipe.

5. The phase-change thermal storage heat sink using thermal expansion of a phase-change material according to claim 1, wherein: the cold plate is in direct contact with the radiating surface of the electronic equipment and is coated with heat-conducting silicone grease.