CN112179179A - Enhanced heat transfer resistance-reducing energy-saving heat exchange plate for fold line type printed circuit board type heat exchanger - Google Patents
Enhanced heat transfer resistance-reducing energy-saving heat exchange plate for fold line type printed circuit board type heat exchanger Download PDFInfo
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- CN112179179A CN112179179A CN202010909562.3A CN202010909562A CN112179179A CN 112179179 A CN112179179 A CN 112179179A CN 202010909562 A CN202010909562 A CN 202010909562A CN 112179179 A CN112179179 A CN 112179179A
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- Prior art keywords
- broken line
- heat exchanger
- heat exchange
- heat transfer
- exchange plate
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- 238000012546 transfer Methods 0.000 title claims abstract description 28
- 238000005728 strengthening Methods 0.000 claims abstract description 37
- 238000005452 bending Methods 0.000 claims abstract description 10
- 238000000034 method Methods 0.000 claims abstract description 9
- 230000008569 process Effects 0.000 claims abstract description 9
- 238000003486 chemical etching Methods 0.000 claims abstract description 8
- 230000003014 reinforcing effect Effects 0.000 claims abstract description 5
- 230000009467 reduction Effects 0.000 claims description 10
- 239000007769 metal material Substances 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 4
- 229910052755 nonmetal Inorganic materials 0.000 claims description 3
- 238000009826 distribution Methods 0.000 abstract description 8
- 230000002708 enhancing effect Effects 0.000 description 3
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 238000004134 energy conservation Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 102100025490 Slit homolog 1 protein Human genes 0.000 description 1
- 101710123186 Slit homolog 1 protein Proteins 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005219 brazing Methods 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
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Classifications
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- 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
- F28D9/00—Heat-exchange apparatus having stationary plate-like or laminated conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
- F28D9/0031—Heat-exchange apparatus having stationary plate-like or laminated conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits for one heat-exchange medium being formed by paired plates touching each other
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
- F28F9/24—Arrangements for promoting turbulent flow of heat-exchange media, e.g. by plates
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
- F28F9/26—Arrangements for connecting different sections of heat-exchange elements, e.g. of radiators
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Fluid Mechanics (AREA)
- Manufacturing Of Printed Circuit Boards (AREA)
Abstract
The invention provides a reinforced heat transfer resistance-reducing energy-saving heat exchange plate for a broken line type printed circuit board type heat exchanger, which comprises a heat exchange plate body, wherein a plurality of broken line runners are arranged on the surface of the heat exchange plate body in parallel, and balance reinforcing seams are processed at the bending angles of the broken line runners. The balance strengthening seam and the broken line runner are integrally processed and formed through a chemical etching process, so that the balance strengthening seam is easy to process, firm in structure and good in economical efficiency; the balance strengthening seam can realize low-speed jet flow among the runners, so that a backflow area is damaged, heat transfer is enhanced, pressure distribution in each runner is more uniform, flow distribution among parallel runners is more uniform, working medium pressure drop in the runners is reduced, and the efficiency of the heat exchanger is further improved; meanwhile, the balance strengthening seam has small influence on the structural strength of the heat exchanger, so that the heat exchanger can continuously keep higher pressure bearing capacity.
Description
Technical Field
The invention belongs to the field of heat exchange structures, and particularly relates to a reinforced heat transfer resistance-reducing energy-saving heat exchange plate of a broken line type printed circuit plate heat exchanger, which is suitable for the engineering thermal physical field with vigorous demands on compact and efficient heat exchange equipment, such as nuclear energy, aerospace, chip cooling and the like.
Background
The broken-line flow channel type printed circuit board heat exchanger (PCHE) has the characteristics of high compactness, small volume, high structural strength, high heat exchanger efficiency, high temperature and pressure bearing capacity and the like. The PCHE is initially applied to the field of low temperature and refrigeration, and recently, with the requirements on energy conservation and emission reduction, a plurality of new energy conservation and emission reduction technologies are proposed, such as a new energy development mode combining supercritical carbon dioxide Brayton cycle solar energy, nuclear energy and traditional fossil energy, and technical concepts of a modular small reactor, an advanced IV-generation reactor and the like. The new technology and concepts urgently need a heat exchanger with compact volume, high heat exchange efficiency and high temperature and pressure bearing capacity. Thus PCHE is receiving increasing attention from the energy and power industry.
Heat exchanger performance is largely determined by the heat exchange surface characteristics, including flow characteristics and heat transfer characteristics of the heat exchange surfaces. The ideal heat exchange surface should have less frictional resistance, thereby reducing the overall power consumption of the heat exchanger; meanwhile, the heat exchanger has a large convection heat transfer coefficient so as to improve the heat exchange efficiency of the heat exchanger.
The structure of the heat exchange plate of the current PCHE is shown in figure 1, wherein a flow channel is chemically etched firstly, a cold flow channel and a hot flow channel are arranged, then a heat exchanger core body is formed by diffusion welding or brazing, and finally the PCHE is formed by assembling accessories. The pressure-bearing capacity of the PCHE can reach 50 MPa, the use temperature can reach 1000 ℃, and the efficiency of the heat exchanger can reach 97%. The material which can be used for processing PCHE (diffusion welding) is wide, and comprises technical materials such as stainless steel, copper, titanium alloy and the like and non-metallic materials such as partial ceramic, glass and the like.
At present, a typical broken-line flow channel type heat exchange plate flow channel structure formed by chemical etching is shown in fig. 2, the structure can increase boundary layer disturbance and enhance the heat transfer capacity between the flow channel surface and a working medium, and the structure has the defects that a downstream backflow area at a bent part increases thermal resistance to influence heat transfer, and the pressure drop of a heat exchanger is larger due to uneven pressure distribution in the flow channel.
Therefore, it is a difficult problem to be solved by those skilled in the art to develop a heat exchange mechanism that can effectively reduce thermal resistance, ensure heat transfer, and make pressure distribution in a flow channel uniform.
Disclosure of Invention
In order to solve the problems, the invention discloses a reinforced heat transfer resistance-reducing energy-saving heat exchange plate for a fold line type printed circuit board type heat exchanger.
In order to achieve the purpose, the invention provides the following technical scheme:
the heat exchange plate comprises a heat exchange plate body with a plurality of fold line runners arranged in parallel on the surface, and balance strengthening seams are processed at the bending angles of the fold line runners.
Further, the width D of the balance strengthening seam is 0.1-0.5 mm.
Furthermore, the azimuth angle theta of the balance strengthening seam is 0-60 degrees.
Further, the distance d between the balance reinforcing seam and the bending angle is 0-16 mm.
Furthermore, the balance strengthening slits and the broken line flow passages are integrally processed and formed through a chemical etching process, and the balance strengthening slits are arranged at the downstream of the bending angles of the broken line flow passages.
Further, the cross section of the balance reinforcing seam is rectangular or semicircular.
Further, the heat exchange plate body is made of a metal material or a non-metal material.
The invention provides a reinforced heat transfer resistance-reducing energy-saving heat exchange plate for a broken line type printed circuit board heat exchanger. The balance strengthening seam realizes low-speed jet flow between the runners, so that a backflow area is damaged, heat transfer is enhanced, pressure distribution in each runner is more uniform, flow distribution among parallel runners is more uniform, pressure drop of working media in the runners is reduced, structural strength of the heat exchanger is less influenced, and the heat exchanger can continuously keep higher pressure bearing capacity.
Meanwhile, the balance strengthening slits and the broken line flow passages are integrally processed and formed through a chemical etching process, and the balance strengthening slits are arranged at the downstream of the bending angles of the broken line flow passages; the width D of the balance strengthening seam is 0.1-0.5 mm, the azimuth angle theta of the balance strengthening seam is 0-60 degrees, the distance D between the balance strengthening seam and the bending angle is 0-16 mm, the specific numerical parameters are reasonably selected according to the heat exchange capacity and the pressure drop requirement of the actual engineering working condition, and the increase of the flow resistance is reasonably controlled while the heat transfer is strengthened as much as possible when the balance strengthening seam is designed so as to reduce the driving power. The structure processed by the scheme can strengthen the heat transfer capacity of the PCHE and improve the efficiency of the heat exchanger.
Compared with the prior art, the invention has the following advantages and beneficial effects:
(1) the balance strengthening seam and the broken line runner are integrally processed and formed through a chemical etching process, so that the balance strengthening seam is easy to process, firm in structure and good in economical efficiency;
(2) the balance strengthening seam can realize low-speed jet flow among the runners, so that a backflow area is damaged, heat transfer is enhanced, pressure distribution in each runner is more uniform, flow distribution among parallel runners is more uniform, working medium pressure drop in the runners is reduced, and the efficiency of the heat exchanger is further improved;
(3) the balance strengthening seam has small influence on the structural strength of the heat exchanger, so that the heat exchanger can continuously keep higher pressure-bearing capacity.
Drawings
FIG. 1, schematic of a prior art PCHE fabrication;
FIG. 2 is a schematic structural diagram of a conventional flow channel with broken lines;
FIG. 3 is a schematic structural view of the present invention;
FIG. 4 is a diagram illustrating the structural parameters of the present invention.
List of reference numerals: balance strengthening seam 1, broken line runner 2, runner inter-rib wall 3, runner midline 4.
Detailed Description
The technical solutions provided by the present invention will be described in detail below with reference to specific examples, and it should be understood that the following specific embodiments are only illustrative of the present invention and are not intended to limit the scope of the present invention.
As shown in fig. 3, the invention relates to a heat exchange plate for enhancing heat transfer, resistance reduction and energy saving of a broken line type printed circuit board heat exchanger, which comprises a heat exchange plate body with a plurality of broken line flow channels 2 arranged in parallel on the surface, wherein balance enhancing slits 1 are processed at the downstream of the bending angles of the broken line flow channels 2, and the balance enhancing slits 1 and the broken line flow channels 2 are integrally processed and formed through a chemical etching process.
The balance strengthening seams 1 are periodically arranged along the flow direction, the cross section of each balance strengthening seam 1 is semicircular, the direction of each balance strengthening seam is perpendicular to the flow direction, and the balance strengthening seams 1 are not etched on the left side and the right side of the heat exchange plate body; a broken-line runner 2 is etched on the same side of the heat exchange plate body etched with the balance strengthening seam 1 through a chemical etching process, the cross section of the broken-line runner 2 is semicircular, and the runner is etched from one end of the heat exchange plate body to the other end.
The heat exchange plate body is made of metal materials or nonmetal materials.
The structural parameters of the balance strengthening joint 1 need to be reasonably selected according to the actual engineering working conditions, and the increase of the flow resistance is reasonably controlled while heat transfer is strengthened as much as possible when the balance strengthening joint 1 is designed so as to reduce the driving work. As shown in fig. 4, the width D of the balance reinforcing slit 1 is 0.2 mm; the azimuth angle theta of the balance strengthening seam 1 is 30 degrees; the distance d between the balance strengthening seam 1 and the bending angle is 2 mm. Compared with a broken line flow channel PCHE without a balance strengthening seam, the heat exchanger can improve the whole convection heat transfer coefficient by about 15% and reduce the pressure drop by about 10% under the same working condition.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting the technical solutions, and those skilled in the art should understand that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions, and all the modifications and equivalent substitutions should be covered by the claims of the present invention.
Claims (7)
1. The utility model provides an energy-conserving heat transfer board of enhanced heat transfer drag reduction for broken line type printed circuit board heat exchanger, includes the heat transfer board body that a plurality of broken line runners of the parallel arrangement in surface, its characterized in that: and a balance strengthening seam is processed at the bending angle of the broken line flow channel.
2. The enhanced heat transfer, resistance reduction and energy saving heat exchange plate for the broken line type printed circuit plate heat exchanger as claimed in claim 1, wherein: the width D of the balance strengthening seam is 0.1-0.5 mm.
3. The enhanced heat transfer, resistance reduction and energy saving heat exchange plate for the broken line type printed circuit plate heat exchanger as claimed in claim 1, wherein: the azimuth angle theta of the balance strengthening seam is 0-60 degrees.
4. The enhanced heat transfer, resistance reduction and energy saving heat exchange plate for the broken line type printed circuit plate heat exchanger as claimed in claim 1, wherein: the distance d between the balance reinforcing seam and the bent angle is 0-16 mm.
5. The enhanced heat transfer, resistance reduction and energy saving heat exchange plate for the broken line type printed circuit plate heat exchanger as claimed in any one of claims 1 to 4, wherein: the balance strengthening seam and the broken line flow passage are integrally processed and formed through a chemical etching process, and the balance strengthening seam is arranged at the downstream of the bending angle of the broken line flow passage.
6. The enhanced heat transfer, resistance reduction and energy saving heat exchange plate for the broken line type printed circuit plate heat exchanger as claimed in claim 5, wherein: the cross section of the balance strengthening seam is rectangular or circular.
7. The enhanced heat transfer, resistance reduction and energy saving heat exchange plate for the broken line type printed circuit plate heat exchanger as claimed in claim 1, wherein: the heat exchange plate body is made of metal materials or nonmetal materials.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010909562.3A CN112179179A (en) | 2020-09-02 | 2020-09-02 | Enhanced heat transfer resistance-reducing energy-saving heat exchange plate for fold line type printed circuit board type heat exchanger |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010909562.3A CN112179179A (en) | 2020-09-02 | 2020-09-02 | Enhanced heat transfer resistance-reducing energy-saving heat exchange plate for fold line type printed circuit board type heat exchanger |
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| Publication Number | Publication Date |
|---|---|
| CN112179179A true CN112179179A (en) | 2021-01-05 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010909562.3A Pending CN112179179A (en) | 2020-09-02 | 2020-09-02 | Enhanced heat transfer resistance-reducing energy-saving heat exchange plate for fold line type printed circuit board type heat exchanger |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113048819A (en) * | 2021-04-26 | 2021-06-29 | 山东大学 | Supercritical CO2Spiral Z-shaped printed circuit board type heat exchanger |
| CN115218710A (en) * | 2022-09-08 | 2022-10-21 | 中国核动力研究设计院 | Heat exchange component, heat exchange core and heat exchange device |
| CN115325717A (en) * | 2022-10-14 | 2022-11-11 | 中国核动力研究设计院 | Heat exchange device and Brayton cycle system |
| CN117091433A (en) * | 2023-08-25 | 2023-11-21 | 西安交通大学 | Airfoil embedded herringbone channel printed circuit board type heat exchanger and control method |
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| CN1502428A (en) * | 1995-12-28 | 2004-06-09 | �Ѻ͵繤��ʽ���� | Process for producing flat heat exchange tubes |
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2020
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113048819A (en) * | 2021-04-26 | 2021-06-29 | 山东大学 | Supercritical CO2Spiral Z-shaped printed circuit board type heat exchanger |
| CN115218710A (en) * | 2022-09-08 | 2022-10-21 | 中国核动力研究设计院 | Heat exchange component, heat exchange core and heat exchange device |
| CN115218710B (en) * | 2022-09-08 | 2022-12-13 | 中国核动力研究设计院 | Heat exchange part, heat exchange core and heat exchange device |
| CN115325717A (en) * | 2022-10-14 | 2022-11-11 | 中国核动力研究设计院 | Heat exchange device and Brayton cycle system |
| CN117091433A (en) * | 2023-08-25 | 2023-11-21 | 西安交通大学 | Airfoil embedded herringbone channel printed circuit board type heat exchanger and control method |
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Application publication date: 20210105 |