KR101778118B1 - Steam generator of the printed circuit heat exchanger type having an orifice - Google Patents

Steam generator of the printed circuit heat exchanger type having an orifice Download PDF

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Publication number
KR101778118B1
KR101778118B1 KR1020160012241A KR20160012241A KR101778118B1 KR 101778118 B1 KR101778118 B1 KR 101778118B1 KR 1020160012241 A KR1020160012241 A KR 1020160012241A KR 20160012241 A KR20160012241 A KR 20160012241A KR 101778118 B1 KR101778118 B1 KR 101778118B1
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South Korea
Prior art keywords
orifice
heat exchanger
region
flow path
orifice region
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Application number
KR1020160012241A
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Korean (ko)
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KR20170091349A (en
Inventor
김용완
김찬수
사인진
김응선
김민환
Original Assignee
한국원자력연구원
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Priority to KR1020160012241A priority Critical patent/KR101778118B1/en
Publication of KR20170091349A publication Critical patent/KR20170091349A/en
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Publication of KR101778118B1 publication Critical patent/KR101778118B1/en

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B3/00—Other methods of steam generation; Steam boilers not provided for in other groups of this subclass
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B3/00—Other methods of steam generation; Steam boilers not provided for in other groups of this subclass
    • F22B3/08—Other methods of steam generation; Steam boilers not provided for in other groups of this subclass at critical or supercritical pressure values
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B37/00—Component parts or details of steam boilers
    • F22B37/02—Component parts or details of steam boilers applicable to more than one kind or type of steam boiler
    • F22B37/10—Water tubes; Accessories therefor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B37/00—Component parts or details of steam boilers
    • F22B37/02—Component parts or details of steam boilers applicable to more than one kind or type of steam boiler
    • F22B37/10—Water tubes; Accessories therefor
    • F22B37/12—Forms of water tubes, e.g. of varying cross-section
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F25/00—Component parts of trickle coolers
    • F28F25/10—Component parts of trickle coolers for feeding gas or vapour
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F3/00—Plate-like or laminated elements; Assemblies of plate-like or laminated elements
    • F28F3/12—Elements constructed in the shape of a hollow panel, e.g. with channels

Abstract

The present invention relates to a printing type heat exchanger type steam generator equipped with an orifice for providing a flow path having an orifice region provided with a multi-stage orifice by forming a concavo-convex structure on a cross section of an orifice region of a flow path by chemical etching, The orifice region 111 is formed in the print heat exchanger 100 to a position spaced a predetermined distance from the inlet where water is introduced, and moves the water flowing from the inlet to raise the pressure. (110) extending from the orifice region (111) and moving the water to be discharged from the orifice region (111) to lower the pressure and converting the water into steam. a and length (l a) has a length (L b), half of the normal passage of the effective heat transfer area of the orifice area (111) (R b) and the orifice region 111 diameter (r a) the doedoe determined based on the diameter of the orifice area 111 (r a) is that as compared to the radius of the normal flow path (R b) smaller the diameter of the Wherein a plurality of plate-shaped plates are respectively etched, etched plates are stacked on each other, the etched portions are formed as a flow passage, and the inner cross-section of the orifice region 111 111b are formed so as to induce pressure intensification, and the lower surface and the upper surface of the print heat exchanger 100 are positioned at the upper portion of the diffusion bonding press where the curved surface is formed and the lower portion of the diffusion bonding press, Wherein the plate is formed by laminating and spreading the plates in a curved shape, wherein a ratio of a radius of curvature to a thickness of the plate is set to 10 or more.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a steam generator of a printed heat exchanger type having an orifice,

The present invention relates to a printing type heat exchanger type steam generator having an orifice, and more particularly, to providing a flow path having an orifice region provided with a multi-stage orifice by forming a concavo-convex structure on the end face of an orifice region of a flow path using a chemical etching method To a steam generator of a printing type heat exchanger system equipped with an orifice.

As a steam generator, a recirculating U-tube type and a peristaltic steam generator used in conventional commercial nuclear reactors are mainly used. First, the U-tube type steam generator has a shape in which the main coolant flows through the tube, the main steam is generated outside the tube, and the steam drier and the wet separator are installed at the top of the steam generator. U tube steam generator is easy to detect leakage and easy to repair or repair. The U-shaped heat transfer tube is not difficult to manufacture, and has many experiment and operation experiences related to heat transfer, so it is easy to design and manufacture. On the other hand, there is a disadvantage that only dry saturated steam can be obtained and the pressure fluctuation of the steam increases when the load is changed.

On the other hand, the once-through steam generator shown in FIG. 1 is a type in which the secondary cooling water evaporates while flowing through the pipe. In this case, the heat transfer area needs about 20% more than the U-type steam generator. Because there may be instability of the flow, it is necessary to maintain the purity of the water supply because the water control system should be sufficient and precise control is possible and all the water in the tubule evaporates.

Since the tube type steam generator has a limitation in manufacturing a small volume, it is possible to use a printed circuit heat exchanger as a steam generator. In this case, it is suitable to produce superheated steam in a once-through mode rather than a recirculation mode. However, printed steam generators have a very large parallel flow path. This is not a problem in a simple gas or liquid heat exchanger, but in a steam generator in which the phase changes, the flow distribution between the flow paths may be changed, and the boundary of the evaporation and superheating regions in the flow path may vibrate, Lt; / RTI > In the flow type steam generator, an orifice is attached to the inlet of the tube to prevent uniform flow distribution and flow instability in the flow paths. When the boundary of the evaporation region oscillates, the surface temperature and the heat transfer coefficient change at a specific position, and the generated thermal stress occurs. Thermal stress can cause fatigue damage accumulation and cause lifetime problems of the equipment, i.e., the steam generator.

Even when a multi-channel print heat exchanger is used as a steam generator, the dry-out boundary moves arbitrarily as in the conventional steam generator. In the case of a printing type heat exchanger, since the diameter of the flow path is less than 3 mm when it is made by chemical etching, it is difficult to mount the orifice like the tube type, and the structure itself and the shape are complicated and uneconomical.

Therefore, the concept of the orifice of the printed heat exchanger and the design and manufacturing method are required.

Korea Patent No. 0621319

The present invention has been made in response to such a need, and it is an object of the present invention to provide an ink jet print head having an orifice for providing a flow path having an orifice region provided with a multi-stage orifice by forming a concavo- And a steam generator of a heat exchanger type. Another object of the present invention is to provide a printing type steam generator equipped with an orifice having a curved surface, which is not a simple plate type heat exchanger type heat exchanger.

The steam generator of the printing type heat exchanger system equipped with the orifice according to the embodiment of the present invention is a steam generator equipped with a printing type heat exchanger used in commercial nuclear reactors. The steam generator includes a steam generator having a printing type heat exchanger An orifice region 111 formed in the printed heat exchanger 100 so as to be spaced from the inlet of the water inlet by a predetermined distance and moving water introduced from the inlet to raise the pressure; And a plurality of flow passages 110 extending from the orifice region 111 and having an effective heat transfer region 112 for transferring the water to be lowered in pressure to convert the water into steam, Wherein the length l a of the orifice region 111 is the length L b of the effective heat transfer region, the radius R b) and doedoe determined based on the diameter (r a) of the orifice region 111, compared to the diameter (r a) is the radius of the normal flow path (R b) of the orifice region 111 is smaller the diameter A plurality of plate-shaped plates are respectively etched, etched plates are stacked one upon the other so that an etched portion forms a flow passage, and an inner end face of the orifice region 111 is pressurized And the upper surface of the print heat exchanger 100 is positioned on the upper part of the diffusion bonding press where the curved surface is formed and the lower part of the diffusion bonding press when the lower surface and the upper surface of the printing heat exchanger 100 are positioned below the diffusion bonding press. Wherein a ratio of a radius of curvature of the plate to a thickness of the plate is set to 10 or more.

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The present invention provides a flow path having an orifice area provided with a multi-stage orifice by forming a concavo-convex structure on the end face of an orifice area of a flow path by using a chemical etching method, thereby reducing the flow path sectional area of the orifice area, It is possible not only to obtain a descent but also to mitigate flow instability.

The present invention also has the effect of reducing the oscillation of the interface of the evaporation region with phase change or reducing the amplitude of oscillation to reduce the fatigue damage by reducing the thermal stress magnitude, thereby reducing the lifetime of the device .

Further, since the present invention does not require the additional pressure drop device, it is possible to design the print heat exchanger in a compact structure.

Further, the present invention has the effect of making it possible to easily adjust the magnitude of pressure drop during the design process.

The present invention also provides a printing type heat exchanger manufactured by a chemical etching method in which a concave-convex structure is formed in an orifice region simultaneously with a flow path etching, thereby realizing a multi-stage orifice and thereby reducing the sectional area of the orifice region, So that there is no need for a separate process for manufacturing the orifice.

In addition, the present invention can prevent the deformation of the flow channel shape when the printing plate is compressed by forming the plurality of flow paths by etching while forming the orifices, and withstand the high differential pressure while maintaining the shape of the flow channel, There is a technical effect that the production efficiency can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view for explaining a vapor boundary vibration state of a general flow type steam generator. FIG.
2 (a) and 2 (b) are views for explaining a printing type heat exchanger.
3 is a view for explaining a plate of a printing type heat exchanger in which a flow path is formed according to the present invention.
Fig. 4 is a view for explaining the orifice region and the effective heat transfer region in the multiple flow paths of Fig. 3;
Fig. 5 is a view showing one flow path shape in Fig. 4, and is a view for explaining the correlation between the orifice region and the effective heat transfer region.
Figs. 6 and 7 are views for explaining the concavo-convex structure formed in the orifice region of Figs. 3 to 5. Fig.
8 is a view for explaining an application example of a printing type heat exchanger to which the present invention is applied.
FIGS. 9 and 10 are views for explaining an application example using a steam generator in which a printing type heat exchanger to which the present invention is applied is diffusion bonded in a curved shape.

It is noted that the technical terms used in the present invention are used only to describe specific embodiments and are not intended to limit the present invention. In addition, the technical terms used in the present invention should be construed in a sense generally understood by a person having ordinary skill in the art to which the present invention belongs, unless otherwise defined in the present invention, Should not be construed to mean, or be interpreted in an excessively reduced sense. In addition, when a technical term used in the present invention is an erroneous technical term that does not accurately express the concept of the present invention, it should be understood that technical terms can be understood by those skilled in the art. In addition, the general terms used in the present invention should be interpreted according to a predefined or prior context, and should not be construed as being excessively reduced.

Furthermore, the singular expressions used in the present invention include plural expressions unless the context clearly dictates otherwise. In the present invention, terms such as "comprising" or "comprising" and the like should not be construed as encompassing various elements or various steps of the invention, Or may further include additional components or steps.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals refer to like or similar elements throughout the several views, and redundant description thereof will be omitted.

2 (a) and 2 (b) are views for explaining a printing type heat exchanger. 3 is a view for explaining a plate of a printing type heat exchanger in which a flow path is formed according to the present invention. Fig. 4 is a view for explaining the orifice region and the effective heat transfer region in the multiple flow paths of Fig. 3; Fig. 5 is a view showing one flow path shape in Fig. 4, and is a view for explaining the correlation between the orifice region and the effective heat transfer region. Figs. 6 and 7 are views for explaining the concavo-convex structure formed in the orifice region of Figs. 3 to 5. Fig. 8 is a view for explaining an application example of a printing type heat exchanger to which the present invention is applied. FIGS. 9 and 10 are views for explaining an application example using a steam generator in which a printing type heat exchanger to which the present invention is applied is diffusion bonded in a curved shape.

As shown in FIG. 2, the printing type heat exchanger 100 to which the present invention is applied includes a plurality of plates laminated. In the plate 100a, as shown in FIG. 3, And are formed parallel to each other in a spaced apart state.

In the printing type heat exchanger 100, a plurality of plates are etched to form a part of the flow path, and a plurality of etched plates are stacked one upon the other so that a channel can be formed in a desired direction at a desired position .

As shown in FIGS. 3 and 4, the flow path 110 is formed to a position spaced from the inlet to which water is introduced, and includes an orifice region 111 for moving water introduced from the inlet to a high pressure, 111) for moving the water discharged from the orifice region (111) to low pressure and converting water into steam.

The orifice region 111 has a constant length as shown in FIG. 5, and a narrow flow path is designed. The length l a of the orifice region 111 is determined based on the length L b of the effective heat transfer region, the radius R b of the normal flow path, and the diameter r a of the orifice region 111. The diameter r a of the orifice region 111 is made small so that the diameter can have a sufficient pressure drop relative to the radius R b of the normal flow path. And an evaporation region and a super heating region where water is evaporated in the effective heat transfer region L b .

In order to obtain a required pressure drop in a narrow space, the flow path is simply formed by reducing the shape of the flow path to r a to secure the orifice region 1110. In order to obtain a high pressure drop in a short length, You may.

6 and 7, the concave and convex structures 111a and 111b are formed in the inner surface of the orifice region 111 to realize a multi-stage orifice in the orifice region 111 So that the flow path cross-sectional area of the orifice region can be reduced. Here, the concavo-convex structures 111a and 111b can be formed by a chemical etching method, but they are formed together when the channel 110 is formed in the plate.

The shape of the concave and convex structures 111a and 111b may be a semicircular shape as shown in Fig. 6 and a rectangular shape as shown in Fig. 7, and the shape of the concave and convex structures 111a and 111b may be elliptical, rectangular, triangular, A pattern may be used so that the shape can be formed at the time of chemical etching after the shape is selected as needed. Thus, an orifice region in which various types of multi-stage orifices are formed can be realized on the flow path.

The concavo-convex structures 111a and 111b are formed by separately etching a plurality of plates, and then the plates are laminated to each other, and the shape and direction thereof are three-dimensional.

At this time, the pressure drop range of the orifice region (l a ) is greater than zero (0) and less than or equal to the pressure drop of the effective heat transfer region (L b ).

The shape of the concave and convex structures 111a and 111b allows the fluid flowing in the flow path to be evaporated at a predetermined position by the user and to reduce vibrations and over-amplitudes with respect to the boundary where the fluid and the vapor are generated do.

In this way, as the amplitude is reduced, the generation of fatigue load is prevented and the service life of the machine can be extended.

8 is a view for explaining an application example of a printing type heat exchanger to which the present invention is applied. The printing type heat exchanger 100 is formed to be curved so as to have a certain curvature, So that a steam generator having a desired size and a desired shape can be realized. That is, a desired steam generator can be manufactured through the modification of the size and shape of the printing type heat exchanger, the orifice area is formed in the flow path of the printing type heat exchanger, and the orifice area is formed in a multi- If there is a difference in the pressure drop of each flow path, the total pressure drop in the orifice region can be controlled to alleviate the flow rate distribution difference of each flow path. This makes it possible to mitigate flow instability.

The print type heat exchanger type steam generator according to the present invention can be manufactured by diffusing and bonding in the form of a curved surface as shown in FIGS. It is applicable when the curvatures of the top and bottom are the same or different. However, when the ratio of the radius of curvature (Rpche-i) to the thickness (Tpche) is 10 or more, diffusion bonding can be applied without stress analysis. When the ratio of the radius of curvature (Rpche-i) to the thickness (Tpche) is 5 to 10, stress analysis is performed on the upper surface and the lower surface of the printing type heat exchanger based on the force applied at the diffusion bonding, Below the yield stress, it should be in the range of 80% or more of the yield stress.

The orifice provided in the steam generator of the printing type heat exchanger system according to the present invention can be applied in the same manner to a printing type heat exchanger in which flow instability may occur in addition to water, for example, a heat exchanger using supercritical carbon dioxide.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or essential characteristics thereof. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

100: printing type heat exchanger 110:
111: Orifice area
111a, 111b: concave and convex structure (concave and convex portions)
112: effective heat transfer area 200: tube

Claims (6)

1. A steam generator provided with a printing type heat exchanger used in a commercial nuclear reactor,
The printing type heat exchanger (100)
An orifice region 111 formed so as to be spaced apart from the inlet where the water is introduced and moving the water introduced from the inlet to raise the pressure,
A flow path 110 composed of an effective heat transfer area 112 extending from the orifice area 111 and moving the water discharged from the orifice area 111 to be lowered to be converted into steam, Is formed,
The length l a of the orifice region 111 is determined based on the length L b of the effective heat transfer region, the radius R b of the normal flow path, and the diameter r a of the orifice region 111, The diameter r a of the orifice region 111 is smaller than the radius R b of the normal flow path,
The printing type heat exchanger (100)
A plurality of plate-shaped plates are respectively etched, etched plates are stacked on each other, and the etched portions are formed as a flow passage, and the inner cross-section of the orifice region 111 is provided with concave and convex structures 111a and 111b, Respectively,
When the printing heat exchanger (100) is positioned at the upper part of the diffusion bonding press where the lower surface and the upper surface are curved respectively and the lower part of the diffusion bonding press, the plates are laminated and bonded in a curved shape, and the curvature radius And a ratio of the thickness of the heat exchanger to the thickness of the steam generator is 10 or more. delete The method according to claim 1,
The printing type heat exchanger (100)
After a plurality of plate-shaped plates are respectively etched, the etched portions are laminated with each other,
Wherein the concave and convex structures (111a) and (111b) are formed by a chemical etching method. The method of claim 3,
Wherein the shape of the concavo-convex structures (111a) and (111b) is one of semicircular, elliptic, quadrangular, triangular, and trapezoidal shapes.

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KR1020160012241A 2016-02-01 2016-02-01 Steam generator of the printed circuit heat exchanger type having an orifice KR101778118B1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102232400B1 (en) 2019-10-29 2021-03-26 한국항공우주연구원 Making method for orifice and the orifice made by the same method

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101966930B1 (en) * 2017-08-25 2019-04-08 한국원자력연구원 Heat exchanger using flash evaporation and steam generator having the same
KR102019203B1 (en) * 2017-10-02 2019-09-06 한국원자력연구원 Printed circuit heat exchange module and heat exchanger
KR102539479B1 (en) * 2020-11-27 2023-06-05 한국원자력연구원 Heat exchanger and nuclear power plant having the same
CN112935507B (en) * 2021-01-29 2022-06-21 中国石油大学(华东) Diffusion welding process for core body of printed circuit board type heat exchanger

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Publication number Priority date Publication date Assignee Title
JP2010133644A (en) * 2008-12-04 2010-06-17 Hitachi Appliances Inc Distributor

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JP2010133644A (en) * 2008-12-04 2010-06-17 Hitachi Appliances Inc Distributor

Non-Patent Citations (1)

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Title
강한옥 외 2명. 일체형원자로 인쇄기판형 증기발생기 열수력학적 설계. 한국유체기계학회 논문집. 제17권, 제6호, pp.77~83 (2014)*

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102232400B1 (en) 2019-10-29 2021-03-26 한국항공우주연구원 Making method for orifice and the orifice made by the same method
US11815056B2 (en) 2019-10-29 2023-11-14 Korea Aerospace Research Institute Method of manufacturing orifice

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