US20160290742A1 - Heat exchanger - Google Patents

Heat exchanger Download PDF

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Publication number
US20160290742A1
US20160290742A1 US15/035,835 US201415035835A US2016290742A1 US 20160290742 A1 US20160290742 A1 US 20160290742A1 US 201415035835 A US201415035835 A US 201415035835A US 2016290742 A1 US2016290742 A1 US 2016290742A1
Authority
US
United States
Prior art keywords
resonance
heat transfer
prevention baffle
transfer tubes
heat
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US15/035,835
Other languages
English (en)
Inventor
Takahiro OKIMOTO
Naoki Suganuma
Toshifumi Kudo
Tetsuya Yamada
Masashi Kitada
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Power Ltd
Original Assignee
Mitsubishi Hitachi Power Systems Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Hitachi Power Systems Ltd filed Critical Mitsubishi Hitachi Power Systems Ltd
Assigned to MITSUBISHI HITACHI POWER SYSTEMS, LTD. reassignment MITSUBISHI HITACHI POWER SYSTEMS, LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KITADA, MASASHI, KUDO, TOSHIFUMI, OKIMOTO, Takahiro, SUGANUMA, NAOKI, YAMADA, TETSUYA
Publication of US20160290742A1 publication Critical patent/US20160290742A1/en
Abandoned legal-status Critical Current

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Classifications

    • 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
    • F28F9/22—Arrangements for directing heat-exchange media into successive compartments, e.g. arrangements of guide plates
    • 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
    • F22B37/20—Supporting arrangements, e.g. for securing water-tube sets
    • 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
    • F28D7/00—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
    • F28D7/16—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being arranged in parallel spaced relation
    • F28D7/1615—Heat-exchange apparatus having stationary tubular conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits being arranged in parallel spaced relation the conduits being inside a casing and extending at an angle to the longitudinal axis of the casing; the conduits crossing the conduit for the other heat exchange medium
    • 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
    • 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
    • F28F9/22—Arrangements for directing heat-exchange media into successive compartments, e.g. arrangements of guide plates
    • F28F2009/222—Particular guide plates, baffles or deflectors, e.g. having particular orientation relative to an elongated casing or conduit
    • F28F2009/224—Longitudinal partitions
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F2265/00—Safety or protection arrangements; Arrangements for preventing malfunction
    • F28F2265/30—Safety or protection arrangements; Arrangements for preventing malfunction for preventing vibrations

Definitions

  • the present invention relates to a heat exchanger disposed on a boiler, for instance, the heat exchanger including a resonance-prevention baffle disposed between a group of heat transfer tubes.
  • a boiler or the like has a heat exchanger disposed in a duct housing forming a flow passage of combustion gas, the heat exchanger including a super-heater, a re-heater, and an economizer, for example.
  • a heat exchanger includes a plurality of heat transfer tubes disposed inside a duct housing, and a medium such as water flowing through the heat transfer tubes is heated by combustion gas to transform into steam. The steam is sent to a steam turbine to be used for power generation.
  • the plurality of heat transfer tubes is disposed so that the axial direction of each heat transfer tube intersects with the flow passage of combustion gas, and spaced in parallel from one another.
  • FIG. 4 is a diagram of an example of a duct wall 100 forming a flow passage of combustion gas g and heat transfer tubes 102 disposed in a grid pattern in the flow passage of the combustion gas g inside the duct wall 100 .
  • FIG. 5 is a diagram of an example of heat transfer tubes 102 disposed in a staggered pattern.
  • Karman vortices e are generated periodically downstream of a heat transfer tube 102 .
  • a generation frequency fk (Hz) of Karman vortices e can be expressed by the following expression:
  • V is a minimum gap flow rate (flow rate between heat transfer tubes)
  • D is an outer diameter of a heat transfer tube.
  • a duct wall orthogonal to a flow of combustion gas and orthogonal to the axial direction of heat transfer tubes has a unique vibrational mode determined by a physical property of the combustion gas g.
  • the unique vibrational frequency fn (Hz) is expressed by the following expression:
  • n 1, 2, 3, . . .
  • c is sonic speed (depending on the temperature of the combustion gas g)
  • L is a distance between duct walls 100 .
  • Tube singing is normally addressed and prevented by avoiding resonance by providing a resonance-prevention baffle of a plate shape along a flow of combustion gas between a group of heat transfer tubes to increase the unique vibrational frequency fn.
  • FIG. 8 is a diagram of an example with such a resonance-prevention baffle plate 104 .
  • a flow passage of combustion gas g is formed by a duct wall 100 .
  • Heat transfer tubes 102 are disposed in a direction orthogonal to a direction of flow of combustion gas g in the flow passage of the combustion gas g.
  • the resonance-prevention baffle plate 104 is disposed between the heat transfer tubes 102 and along a direction of flow of the combustion gas g.
  • Patent Documents 1 and 2 disclose a heat exchanger including: a plurality of heat transfer tubes disposed in parallel in a flow passage of heat-exchange target gas; and a resonance-prevention baffle plate disposed along a direction of flow of a heat-exchange target fluid between the heat transfer tubes.
  • a typical resonance-prevention baffle plate has a heavy weight, and a significant amount of work hours and cost may be required to fix a resonance-prevention baffle plate with a heavy weight in a flow passage of a heat-exchange target fluid.
  • an object of the present invention is to make configuration and installation work of a resonance-prevention baffle plate simple and less expensive.
  • a heat exchanger comprises: a plurality of heat transfer tubes disposed in parallel and spaced from one another, an axial direction of each heat transfer tube intersecting with a flow passage of a heat-exchange target fluid; and a resonance-prevention baffle having a plate shape and disposed along a flow direction of the heat-exchange target fluid and between the plurality of heat transfer tubes, the resonance-prevention baffle comprising a metal foil sheet.
  • a resonance-prevention baffle plate has a function to increase a unique vibrational frequency fn generated inside a duct wall forming the flow passage of the heat-exchange target fluid and to differentiate the unique vibrational frequency fn from a frequency fk generated by Karman vortices e produced downstream of the heat transfer tubes.
  • the unique vibrational frequency fn can be increased by partitioning the flow passage of the heat-exchange target fluid and forming a boundary where the particle velocity of the heat-exchange target fluid is zero.
  • the above function can be achieved even by a thin partition wall such as a metal foil sheet.
  • the resonance-prevention baffle includes a metal foil sheet and thus can be reduced in weight.
  • the resonance-prevention baffle plate includes a metal foil sheet and thus can be reduced in weight.
  • An embodiment of the present invention further comprises a rigid frame member fixed to an outer peripheral portion of the metal foil sheet.
  • a metal foil sheet may deform in response to a heat-exchange target fluid.
  • the rigid frame member being fixed to the metal foil sheet, it is possible to apply rigidity to the metal foil sheet. Accordingly, it is possible to prevent deformation of the metal foil sheet and to maintain rigidity such that the metal foil sheet does not deform in response to a flow of a heat-exchange target fluid, without increasing too much weight.
  • the resonance-prevention baffle is fixed to at least a part of the plurality of heat transfer tubes by a fixing member.
  • the resonance-prevention baffle of the present invention can be reduced in weight, it is possible to mount the resonance-prevention baffle to the heat transfer tube readily by using a fixing member with less strength. Furthermore, since the resonance-prevention baffle has less weight, it is sufficient if the resonance-prevention baffle is fixed to only a part of the heat exchanger tubes, which reduces the load of mounting work.
  • the fixing member comprises a U-shape bolt disposed so as to surround the heat transfer tube and screwed to the resonance-prevention baffle at opposite ends.
  • the plurality of heat transfer tubes is disposed linearly along the flow direction of the heat-exchange target fluid, and the resonance-prevention baffle is formed into a flat plate shape and disposed along the flow direction of the heat-exchange target fluid.
  • the resonance-prevention baffle includes a metal foil sheet and thus has less weight, which makes it possible to make mounting work of the resonance-prevention baffle simple and less expensive.
  • FIG. 1 is a front cross-sectional view of a heat exchanger according to the first embodiment of the present invention.
  • FIG. 2 is a pre-assembly perspective view of a resonance-prevention baffle plate of the heat exchanger.
  • FIG. 3 is a post-assembly perspective view of the resonance-prevention baffle plate.
  • FIG. 4 is a front cross-sectional view of a general grid-pattern arrangement of heat transfer tubes.
  • FIG. 5 is a front cross-sectional view of a general staggered arrangement of heat transfer tubes.
  • FIG. 6 is a diagram for describing Karman vortices e generated downstream of a heat transfer tube.
  • FIG. 7 is a diagram for describing unique vibration generated inside a duct wall of a heat exchanger.
  • FIG. 8 is a front cross-sectional view of a typical heat exchanger.
  • a heat exchanger according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 3 .
  • the present embodiment is an example in which a heat exchanger 10 according to the first embodiment of the present invention is applied to a heat exchanger such as a super-heater, a re-heater, and an economizer, or to a waste-heat recovery boiler, for instance, disposed on a steam boiler incorporated into a thermal power generation plant.
  • a flow passage of combustion gas g is formed by a duct housing constituting the heat exchanger 10 of the present embodiment.
  • a plurality of heat transfer tubes 14 is disposed inside a duct wall 12 constituting the duct housing.
  • the duct housing has, for instance, a quadrilateral or circular cross section.
  • the heat transfer tubes 14 are disposed in parallel and spaced from one another, and the axial direction of each heat transfer tube 14 is orthogonal to the combustion gas g.
  • the heat transfer tubes 14 are arranged in a grid pattern. Specifically, the heat transfer tubes 14 are arranged in lines extending linearly in a direction of flow of the combustion gas g, and also in a direction orthogonal to the direction of flow of the combustion gas g.
  • the combustion gas g exchanges heat with a medium such as water flowing inside each heat transfer tube 14 while flowing between the heat transfer tubes 14 , and the medium such as water is heated by the combustion gas g to transform into steam.
  • the steam is sent to a steam turbine to be used for power generation.
  • the resonance-prevention baffle 16 includes a metal foil sheet 18 having a flat surface and is disposed along the direction of flow of the combustion gas g. As described above, the resonance-prevention baffle 16 is disposed to partition the flow passage of the combustion gas g, thereby forming a boundary in a flow rate of the combustion gas g. Accordingly, it is possible to increase a resonance frequency generated inside the duct wall 12 .
  • the unique vibrational frequency fn of the unique vibrational mode formed inside the duct wall 12 by the flow of the combustion gas g is differentiated from the generation frequency fk of Karman vortices e generated behind each heat transfer tube 14 , which makes it possible to prevent generation of excessive noise.
  • the resonance-prevention baffle plate 16 includes a metal foil sheet 18 of a quadrilateral shape made of high-temperature stainless steel (SUH 409L) having a thickness of 10 to 1000 ⁇ m, for example, 20 ⁇ m.
  • SAH 409L high-temperature stainless steel
  • the material of the metal foil sheet 18 is selected on the basis of the temperature of a heat-exchange target fluid, and the thickness of the metal foil sheet 18 is selected on the basis of the hardness, viscosity, or the like of the selected material.
  • the length of a side of the metal foil sheet used in the present invention is determined on the basis of the length of a boiler casing and the number of stages of a heat exchanger, and is 20 m (duct width) ⁇ 2 m (number of stages of a heat exchanger), for instance.
  • the metal foil sheet 18 deforms in response to a flow of combustion gas.
  • an outer peripheral portion of the metal foil sheet 18 is nipped by frame members 20 , 20 having rigidity from both sides.
  • the two frame members 20 are fastened by bolts 22 and nuts 24 at where needed. It should be noted that head portions of the bolts 22 and the nuts 24 should be buried into the frame members 20 , 20 as much as possible so as not to generate a turbulence in the flow of combustion gas.
  • the resonance-prevention baffle plate 16 is fixed to the heat transfer tubes 14 by using a U-shape bolt 26 .
  • the U-shape bolt 26 has male screws formed on opposite ends, and is disposed so as to surround the heat transfer tube 14 , and the male screws of the opposite ends of the U-shape bolt 26 are engaged with female screw holes formed on the resonance-prevention baffle plate 16 .
  • the opposite ends may be inserted through holes formed on the resonance-prevention baffle plate 16 , and the male screws may be engaged with nuts 28 to fix the resonance-prevention baffle plate 16 to the heat transfer tube 14 .
  • a position of mounting using the U-shape bolt 26 may be a position required to achieve a necessary fixing strength of the resonance-prevention baffle 16 .
  • the resonance-prevention baffle plate 16 includes the metal foil sheet 18 and thus can be reduced in weight. Thus, it is possible to reduce material cost and to make works required to mount and replace the resonance-prevention baffle plate 16 simple and less expensive.
  • the resonance-prevention baffle plate 16 can be reduced in weight, it is possible to mount the resonance-prevention baffle plate 16 to the heat transfer tube 14 readily by using a fixing member with less strength. Thus, it is possible to fix the resonance-prevention baffle plate 16 firmly by using a less expensive fixing member.
  • the resonance-prevention baffle plate 16 has less weight, it is sufficient if the resonance-prevention baffle plate 16 is fixed to only a part of the heat transfer tubes 14 , which reduces the load of mounting work.
  • the U-shape bolt 26 is used as a fixing unit of the resonance-prevention baffle plate 16 , it is possible to simplify the mounting work even further.
  • the heat transfer tubes 14 are disposed in a grid pattern and the resonance-prevention baffle plate 16 is formed into a flat plate shape, which makes it possible to readily insert the resonance-prevention baffle plate 16 between the heat transfer tubes 14 , which are ready-made members, and to set the resonance-prevention baffle plate 16 in a predetermined position.
  • the present invention is applied to a heat exchanger including heat transfer tubes disposed in a grid pattern.
  • the present invention can be also applied to a heat exchanger including heat transfer tubes disposed in a staggered or zig-zag pattern by modifying a method to fix a metal foil sheet.
  • a heat exchanger including a plurality of heat transfer tubes disposed in parallel and a resonance-prevention baffle plate disposed between the heat transfer tubes, it is possible to make configuration and installation work of a resonance-prevention baffle plate simple and less expensive.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
US15/035,835 2013-12-27 2014-09-10 Heat exchanger Abandoned US20160290742A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2013271370A JP5964286B2 (ja) 2013-12-27 2013-12-27 熱交換器
JP2013-271370 2013-12-27
PCT/JP2014/073986 WO2015098198A1 (ja) 2013-12-27 2014-09-10 熱交換器

Publications (1)

Publication Number Publication Date
US20160290742A1 true US20160290742A1 (en) 2016-10-06

Family

ID=53478081

Family Applications (1)

Application Number Title Priority Date Filing Date
US15/035,835 Abandoned US20160290742A1 (en) 2013-12-27 2014-09-10 Heat exchanger

Country Status (6)

Country Link
US (1) US20160290742A1 (ja)
JP (1) JP5964286B2 (ja)
KR (1) KR20160074655A (ja)
CN (1) CN105659048A (ja)
DE (1) DE112014006052T5 (ja)
WO (1) WO2015098198A1 (ja)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150285270A1 (en) * 2012-11-14 2015-10-08 The Technology Partnership Plc Pump
US20170044968A1 (en) * 2015-08-10 2017-02-16 Indmar Products Company Inc. Marine Engine Heat Exchanger
US9958217B1 (en) * 2013-06-19 2018-05-01 Nooter/Eriksen, Inc. Baffle system and method for a heat exchanger located within a casing of a heat recovery steam generator
US11105569B2 (en) * 2019-03-05 2021-08-31 Hamilton Sundstrand Corporation Heat exchanger spray tube
WO2022117129A1 (en) * 2020-12-01 2022-06-09 Vysoké Učení Technické V Brně Tubular shell heat exchanger with cross flow

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5971092A (ja) * 1982-10-18 1984-04-21 横河電機株式会社 画像デ−タ処理装置
JPH11223329A (ja) * 1998-02-06 1999-08-17 Mitsubishi Heavy Ind Ltd 灰粒子堆積防止セラミック吸音板
JP2001349505A (ja) * 2000-06-07 2001-12-21 Mitsubishi Heavy Ind Ltd ボイラ用騒音防止装置

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5912293A (ja) * 1982-07-12 1984-01-21 Mitsubishi Heavy Ind Ltd 熱交換器における防振バツフル
JPS5971092U (ja) * 1982-11-05 1984-05-14 三菱重工業株式会社 多管式熱交換器におけるバツフル板構造
JPS59108087U (ja) * 1982-12-29 1984-07-20 三菱重工業株式会社 防振型熱交換器
JPS61134595A (ja) * 1984-12-05 1986-06-21 Mitsubishi Heavy Ind Ltd 熱交換器の伝熱管防振支持装置
JP2635869B2 (ja) 1991-11-20 1997-07-30 株式会社東芝 熱交換器
CN201657504U (zh) * 2009-12-29 2010-11-24 深南电路有限公司 板件固定边框

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5971092A (ja) * 1982-10-18 1984-04-21 横河電機株式会社 画像デ−タ処理装置
JPH11223329A (ja) * 1998-02-06 1999-08-17 Mitsubishi Heavy Ind Ltd 灰粒子堆積防止セラミック吸音板
JP2001349505A (ja) * 2000-06-07 2001-12-21 Mitsubishi Heavy Ind Ltd ボイラ用騒音防止装置

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
JP2001-1349505 translation *
JPH11-223329 translation *
JPS59-71092 translation *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150285270A1 (en) * 2012-11-14 2015-10-08 The Technology Partnership Plc Pump
US9958217B1 (en) * 2013-06-19 2018-05-01 Nooter/Eriksen, Inc. Baffle system and method for a heat exchanger located within a casing of a heat recovery steam generator
US20170044968A1 (en) * 2015-08-10 2017-02-16 Indmar Products Company Inc. Marine Engine Heat Exchanger
US9897386B2 (en) * 2015-08-10 2018-02-20 Indmar Products Company Inc. Marine engine heat exchanger
US10465989B2 (en) 2015-08-10 2019-11-05 Indmar Products Company Inc. Marine engine heat exchanger
US11105569B2 (en) * 2019-03-05 2021-08-31 Hamilton Sundstrand Corporation Heat exchanger spray tube
WO2022117129A1 (en) * 2020-12-01 2022-06-09 Vysoké Učení Technické V Brně Tubular shell heat exchanger with cross flow

Also Published As

Publication number Publication date
DE112014006052T5 (de) 2016-09-15
KR20160074655A (ko) 2016-06-28
CN105659048A (zh) 2016-06-08
JP2015124966A (ja) 2015-07-06
JP5964286B2 (ja) 2016-08-03
WO2015098198A1 (ja) 2015-07-02

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Owner name: MITSUBISHI HITACHI POWER SYSTEMS, LTD., JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:OKIMOTO, TAKAHIRO;SUGANUMA, NAOKI;KUDO, TOSHIFUMI;AND OTHERS;REEL/FRAME:038973/0850

Effective date: 20160603

STCB Information on status: application discontinuation

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