CN114152132B - Micro-channel heat exchanger based on Dien vortex - Google Patents
Micro-channel heat exchanger based on Dien vortex Download PDFInfo
- Publication number
- CN114152132B CN114152132B CN202111385908.5A CN202111385908A CN114152132B CN 114152132 B CN114152132 B CN 114152132B CN 202111385908 A CN202111385908 A CN 202111385908A CN 114152132 B CN114152132 B CN 114152132B
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- China
- Prior art keywords
- liquid supply
- plate
- channel
- channels
- corrugated
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- RPNUMPOLZDHAAY-UHFFFAOYSA-N Diethylenetriamine Chemical compound NCCNCCN RPNUMPOLZDHAAY-UHFFFAOYSA-N 0.000 title description 6
- 239000007788 liquid Substances 0.000 claims abstract description 123
- 238000000034 method Methods 0.000 claims abstract description 16
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 8
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 8
- 239000010703 silicon Substances 0.000 claims abstract description 8
- 238000007599 discharging Methods 0.000 claims description 8
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 7
- 229910052802 copper Inorganic materials 0.000 claims description 7
- 239000010949 copper Substances 0.000 claims description 7
- 238000005530 etching Methods 0.000 claims description 4
- 239000000758 substrate Substances 0.000 claims description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims 2
- 229910052760 oxygen Inorganic materials 0.000 claims 2
- 239000001301 oxygen Substances 0.000 claims 2
- 230000006835 compression Effects 0.000 claims 1
- 238000007906 compression Methods 0.000 claims 1
- 239000012530 fluid Substances 0.000 abstract description 12
- 238000005520 cutting process Methods 0.000 abstract description 7
- 239000002184 metal Substances 0.000 abstract 2
- 230000000694 effects Effects 0.000 description 5
- 230000004907 flux Effects 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 244000137852 Petrea volubilis Species 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000002848 electrochemical method Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F13/00—Arrangements for modifying heat-transfer, e.g. increasing, decreasing
- F28F13/06—Arrangements for modifying heat-transfer, e.g. increasing, decreasing by affecting the pattern of flow of the heat-exchange media
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
- F28D2021/0019—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for
- F28D2021/0028—Other heat exchangers for particular applications; Heat exchange systems not otherwise provided for for cooling heat generating elements, e.g. for cooling electronic components or electric devices
- F28D2021/0029—Heat sinks
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
Abstract
The invention discloses a micro-channel heat exchanger based on dean vortex, which comprises a cover plate, a corrugated micro-channel plate, an isobaric liquid supply and discharge loop plate and a bottom plate. The cover plate is a straight high-heat-conductivity metal plate; the corrugated microchannel plate is a silicon plate etched with corrugated microchannels; the isobaric liquid supply and discharge loop plate is a silicon plate which is processed by linear cutting and provided with a liquid supply and discharge loop; the bottom plate is a metal plate welded with a liquid supply joint. The cover plate, the corrugated microchannel plate, the isobaric liquid supply and discharge loop plate and the bottom plate are electrostatically adsorbed together through a bonding process to form the microchannel heat exchanger. The corrugated structure in the micro-channel heat exchanger can induce dean vortex, promote the heat transfer process of fluid in the micro-channel heat exchanger, and reduce the flow pressure loss of the micro-channel heat exchanger.
Description
Technical Field
The invention belongs to the field of enhanced heat exchange, and particularly relates to a micro-channel heat exchanger based on a Dien vortex effect.
Background
The micro-channel heat exchanger is an efficient heat exchanger with the diameter of a fluid channel of 0.3-2 mm, and can provide a very large heat exchange area in a small space so as to realize a high heat flux heat transfer process. And because the fluid molecules in the micro-channel are regularly distributed, the heat transfer process is more efficient than the pipeline fluid heat transfer process, and the method has great development potential. The currently provided microchannel heat exchangers, such as the microchannel heat exchangers of patent numbers CN111900143A and CN209896047U, adopt a flat microchannel heat exchange structure, have the advantages of general heat transfer effect, large working medium flow velocity and large flowing work loss, and are difficult to meet the surface heat flux density of 1000W/cm of a high-power laser and electronic equipment 2 The above heat exchange is required.
Disclosure of Invention
The invention aims to provide a micro-channel heat exchanger based on the Dien vortex effect. Dean vortex is a vortex generated by the influence of curvature effect when fluid flows in a curved flow channel, and the vortex redistributes the velocity field and the pressure field of the fluid, so that the heat and mass transfer performance of the fluid is improved. The invention uses the ripple micro-channel and the isobaric liquid supply and discharge loop to induce dean vortex in the micro-channel, so as to meet the high heat flux density heat exchange requirement of the surface of the micro-channel heat exchanger under low flow resistance and maintain the normal operation of heating equipment.
The technical solution for realizing the purpose of the invention is as follows:
a micro-channel heat exchanger based on Dien vortex comprises a cover plate, a corrugated micro-channel plate, an isobaric liquid supply and discharge loop plate and a base plate which are sequentially arranged;
the corrugated microchannel plate is provided with a plurality of corrugated microchannels which are arranged in parallel at equal intervals and are used for generating dean vortex;
a plurality of groups of main liquid supply channels and main liquid discharge channels which are parallel to each other are respectively arranged on the isobaric liquid supply and discharge loop board;
the main liquid supply channels and the main liquid discharge channels are arranged in a staggered mode at intervals, and the interval distance between the adjacent main liquid supply channels and the adjacent main liquid discharge channels is one fluctuation period of the corrugated micro-channels;
the main liquid supply channel and the main liquid discharge channel are intersected with the corrugated micro-channel;
a plurality of liquid supply sub-channels are arranged on each main liquid supply channel at equal intervals, and the liquid supply sub-channels sequentially lengthen towards the direction away from the liquid supply port of the main liquid supply channel;
a plurality of liquid discharge sub-channels are arranged on each main liquid discharge channel at equal intervals, and the liquid discharge sub-channels sequentially lengthen towards a liquid outlet port far away from the main liquid discharge channel;
the spacing distance between the adjacent liquid supply sub-channels and the adjacent liquid discharge sub-channels is the spacing distance between the adjacent corrugated micro-channels;
the liquid supply sub-channel and the liquid discharge sub-channel are intersected with the corrugated micro-channel, and the intersection positions are the straight section positions of the corrugated micro-channel and are parallel to the liquid flow direction in the straight section;
the substrate is used for liquid supply and liquid discharge.
Compared with the prior art, the invention has the remarkable advantages that:
(1) The invention induces dean vortex of fluid in the micro-channel through the corrugated micro-channel structure, and obtains better heat transfer effect under the same pressure loss;
(2) Through the isobaric liquid supply and discharge loop, the liquid supply pressure at two ends of the corrugated micro-channel is consistent, dean vortex with the same strength is generated in the micro-channel heat exchanger, and the heat exchange capacity of the micro-channel heat exchanger is evenly distributed.
Drawings
Fig. 1 is an isometric view of a cover plate of a microchannel heat exchanger.
Fig. 2 is an isometric view of a corrugated microchannel plate of a microchannel heat exchanger.
Fig. 3 is an isometric view and top view of a microchannel heat exchanger isopiestic liquid supply and drain circuit board.
Fig. 4 is a diagram of the relative positions of a corrugated microchannel plate and an isobaric liquid supply and discharge circuit plate of the microchannel heat exchanger.
Fig. 5 is an isometric view of a microchannel heat exchanger substrate.
Fig. 6 is an exploded view and an assembled view of a microchannel heat exchanger.
FIG. 7 is a graph of cloud and pressure gradient of pressure distribution in a micro-channel after Dien vortex induction.
Fig. 8 is a graph of the temperature of the bottom surface of the microchannel heat sink during operation.
Description of the embodiments
The invention is further described with reference to the drawings and specific embodiments.
Referring to fig. 1-6, the invention discloses a micro-channel heat exchanger based on dean vortex, which comprises a cover plate 1, a corrugated micro-channel plate 2, an isobaric liquid supply and discharge loop plate 3 and a base plate 4 which are sequentially arranged; the cover plate 1 is a flat oxygen-free copper sheet; the corrugated microchannel plate 2 is a thin silicon plate, a plurality of corrugated microchannels which are arranged in parallel at equal intervals are processed by an etching process, the corrugated microchannel structure is an equal-width microchannel with the central line of a wavy line formed by a plurality of groups of elbow sections which are distributed at intervals and straight sections, and the straight sections are connected with adjacent elbow sections and are processed by the etching process. The isobaric liquid supply and discharge loop plate 3 is a thick silicon plate, a linear cutting process is adopted for cutting out a plurality of groups of main liquid supply channels 5 and main liquid discharge channels 6 which are parallel to each other, the main liquid supply channels 5 and the main liquid discharge channels 6 are arranged in a staggered mode at intervals, and the interval distance between every two adjacent main liquid supply channels 5 and main liquid discharge channels 6 is one fluctuation period distance of the corrugated micro-channels. The main liquid supply channel 5 and the main liquid discharge channel 6 are intersected with the corrugated micro-channel, and the flow directions of the main liquid supply channel 5 and the main liquid discharge channel 6 are perpendicular to the whole length direction of the corrugated micro-channel. A plurality of liquid supply sub-channels 7 are arranged on each main liquid supply channel 5 at equal intervals, and the liquid supply sub-channels 7 sequentially lengthen towards the direction of the liquid supply port far away from the main liquid supply channel 5. The spacing distance between adjacent liquid supply sub-channels 7 is the spacing distance between adjacent corrugated micro-channels. A plurality of liquid discharging sub-channels 8 are arranged on each main liquid discharging channel 6 at equal intervals, and the liquid discharging sub-channels 8 sequentially lengthen towards a liquid outlet port far away from the main liquid discharging channel 6. The spacing distance of adjacent liquid discharge sub-channels 8 is the spacing distance of adjacent corrugated micro-channels. The liquid supply sub-channel 7 and the liquid discharge sub-channel 8 are intersected with the corrugated micro-channel. The liquid supply sub-channel 7 and the liquid discharge sub-channel 8 are arranged at the middle position (namely the straight section position) of the wave crest and the wave trough of the corrugated micro-channel and are parallel to the liquid flow direction at the middle position. The base plate 4 is an oxygen-free copper plate, two sides of the plate are respectively provided with a liquid supply channel and a liquid discharge channel, the liquid supply channel and the liquid discharge channel are welded with pipeline joints, and the pipeline joints are respectively connected with a plurality of main liquid supply channels 5 and a plurality of main liquid discharge channels 6 through the liquid supply channels and the liquid discharge channels to supply liquid and discharge liquid.
Further, the cover plate 1, the corrugated microchannel plate 2, the isobaric liquid supply and drainage loop plate 3 and the base plate 4 are formed by pressing through a bonding process, and a complete runner structure is formed.
Furthermore, in the working process of the microchannel heat exchanger, fluid is input from the base plate 4 and is input into the corrugated microchannel plate 2 through the main liquid supply channel 5 on the isobaric liquid supply and discharge loop plate 3, the liquid supply pressure of the main liquid supply channel 5 near the liquid inlet port is large, but the liquid supply flow and the liquid supply pressure of each corrugated microchannel are similar through the throttling of the liquid supply sub-channel 7 with the shorter liquid supply channel near end. Referring to fig. 7, fluid flowing into the corrugated microchannel creates dean vortices at the corners of the corrugations, redistributes the pressure field of the fluid and promotes the heat transfer process, and the dean vortices gradually fade as they flow between the corners until re-intensification at the next corner. The fluid discharged from the corrugated microchannel plate 2 is throttled by liquid discharge sub-channels 8 with different lengths to form a flow field with similar pressure and is discharged, so that the phenomenon that the liquid discharge pressure between different corrugated microchannels is inconsistent to generate countercurrent is avoided.
Examples
The present embodiment is implemented on the premise of the technical scheme of the present invention, and a detailed implementation manner and a specific operation process are given, but the protection scope of the present invention is not limited to the following examples.
(1) Cutting an oxygen-free copper plate with the thickness of 1 mm to manufacture a cover plate, deburring, flattening and polishing the surface of the cover plate to be smooth by using fine sand paper;
(2) Selecting a P-type silicon wafer with the thickness of 3 mm, and etching the corrugated microchannel structure with the width of 0.5 mm by using an electrochemical method to obtain a corrugated microchannel plate with the thickness of 2 mm;
(3) Selecting a silicon wafer with the thickness of 10 mm, and cutting a liquid supply and discharge channel with the width of 1 mm and a liquid supply and discharge sub-channel with the width of 0.5 mm by using a linear cutting method to obtain an isobaric liquid supply and discharge loop board with the thickness of 10 mm;
(4) Cutting 2 oxygen-free copper plates with the thickness of 5 and mm to manufacture a bottom plate, milling liquid supply channels and bonding channels on two sides of the copper plates, and welding liquid supply connecting pipes to form the bottom plate;
(5) The cover plate, the corrugated microchannel plate, the isobaric liquid supply and discharge loop plate and the bottom plate are sequentially cleaned by sodium hydroxide, ethanol and deionized water, the 4 plates are connected together by adopting a bonding process, and the four plates are tightly connected under electrostatic adsorption;
(6) Numerical simulations of the corrugated microchannel heat exchanger showed that the microchannel heat exchanger produced a non-uniform pressure field under the influence of dean vortex (FIG. 7), at 50W/cm 2 The highest temperature of the bottom surface of the heat sink was 121 c (fig. 8) at the high heat flux.
Claims (8)
1. The micro-channel heat exchanger based on dean vortex is characterized by comprising a cover plate, a corrugated micro-channel plate, an isobaric liquid supply and discharge loop plate and a base plate which are sequentially arranged;
the corrugated microchannel plate is provided with a plurality of corrugated microchannels which are arranged in parallel at equal intervals and are used for generating dean vortex;
a plurality of groups of main liquid supply channels and main liquid discharge channels which are parallel to each other are respectively arranged on the isobaric liquid supply and discharge loop board;
the main liquid supply channels and the main liquid discharge channels are arranged in a staggered mode at intervals, and the interval distance between the adjacent main liquid supply channels and the adjacent main liquid discharge channels is one fluctuation period of the corrugated micro-channels;
the main liquid supply channel and the main liquid discharge channel are intersected with the corrugated micro-channel;
a plurality of liquid supply sub-channels are arranged on each main liquid supply channel at equal intervals, and the liquid supply sub-channels sequentially lengthen towards the direction away from the liquid supply port of the main liquid supply channel;
a plurality of liquid discharging sub-channels are arranged on each main liquid discharging channel at equal intervals, and the liquid discharging sub-channels sequentially lengthen towards a liquid outlet port far away from the main liquid discharging channel;
the spacing distance between the adjacent liquid supply sub-channels and the adjacent liquid discharge sub-channels is the spacing distance between the adjacent corrugated micro-channels;
the liquid supply sub-channel and the liquid discharge sub-channel are intersected with the corrugated micro-channel, and the intersection positions are the straight section positions of the corrugated micro-channel and are parallel to the liquid flow direction in the straight section;
the substrate is used for liquid supply and liquid discharge.
2. The dean vortex based microchannel heat exchanger of claim 1, wherein the cover plate, corrugated microchannel plate, isobaric liquid supply circuit plate, and base plate are compression molded using a bonding process.
3. The dean vortex based microchannel heat exchanger of claim 1 wherein the cover plate is an oxygen free copper plate.
4. The dean vortex based microchannel heat exchanger of claim 1, wherein the corrugated microchannel plate is a silicon plate.
5. The dean vortex based microchannel heat exchanger of claim 1 wherein the isobaric liquid supply and drain circuit board is a silicon plate.
6. The dean vortex based microchannel heat exchanger of claim 1 wherein the microchannels are comprised of a plurality of sets of spaced apart elbow sections and straight sections.
7. The dean vortex based microchannel heat exchanger of claim 1 wherein the microchannels are formed using an etching process.
8. The dean vortex based microchannel heat exchanger of claim 1 wherein the base plate is an oxygen free copper plate.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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CN202111385908.5A CN114152132B (en) | 2021-11-22 | 2021-11-22 | Micro-channel heat exchanger based on Dien vortex |
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CN202111385908.5A CN114152132B (en) | 2021-11-22 | 2021-11-22 | Micro-channel heat exchanger based on Dien vortex |
Publications (2)
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CN114152132A CN114152132A (en) | 2022-03-08 |
CN114152132B true CN114152132B (en) | 2024-02-20 |
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CN202111385908.5A Active CN114152132B (en) | 2021-11-22 | 2021-11-22 | Micro-channel heat exchanger based on Dien vortex |
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Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104154798A (en) * | 2014-04-24 | 2014-11-19 | 中国科学院广州能源研究所 | Novel plane micro-channel heat exchanger |
CN109622078A (en) * | 2018-12-11 | 2019-04-16 | 西安交通大学 | A kind of micro-fluidic chip for the single position enrichment of particle in non-newtonian fluid |
KR20210085730A (en) * | 2019-12-31 | 2021-07-08 | 고려대학교 산학협력단 | Liquid-cooled heat sink |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
TWI400421B (en) * | 2010-01-14 | 2013-07-01 | Asia Vital Components Co Ltd | Heat exchanger structure |
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2021
- 2021-11-22 CN CN202111385908.5A patent/CN114152132B/en active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104154798A (en) * | 2014-04-24 | 2014-11-19 | 中国科学院广州能源研究所 | Novel plane micro-channel heat exchanger |
CN109622078A (en) * | 2018-12-11 | 2019-04-16 | 西安交通大学 | A kind of micro-fluidic chip for the single position enrichment of particle in non-newtonian fluid |
KR20210085730A (en) * | 2019-12-31 | 2021-07-08 | 고려대학교 산학협력단 | Liquid-cooled heat sink |
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Inventor after: Hu Dinghua Inventor after: Li Qiang Inventor after: Lin Ken Inventor after: Cao Ning Inventor before: Lin Ken Inventor before: Cao Ning Inventor before: Hu Dinghua Inventor before: Li Qiang |
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