CN102472588A - Method of operating an assembly of heat exchangers for subcritical and transcritical conditions, and an assembly of heat exchangers - Google Patents

Method of operating an assembly of heat exchangers for subcritical and transcritical conditions, and an assembly of heat exchangers Download PDF

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Publication number
CN102472588A
CN102472588A CN2010800301916A CN201080030191A CN102472588A CN 102472588 A CN102472588 A CN 102472588A CN 2010800301916 A CN2010800301916 A CN 2010800301916A CN 201080030191 A CN201080030191 A CN 201080030191A CN 102472588 A CN102472588 A CN 102472588A
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CN
China
Prior art keywords
heat exchanger
assembly
pipeline
heat exchangers
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.)
Pending
Application number
CN2010800301916A
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Chinese (zh)
Inventor
R·克里斯坦森
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Alfa Laval AB
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Alfa Laval AB
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Filing date
Publication date
Application filed by Alfa Laval AB filed Critical Alfa Laval AB
Publication of CN102472588A publication Critical patent/CN102472588A/en
Pending legal-status Critical Current

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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
    • F28D1/00—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
    • F28D1/02—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
    • F28D1/04—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid with tubular conduits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B6/00—Compression machines, plants or systems, with several condenser circuits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B6/00—Compression machines, plants or systems, with several condenser circuits
    • F25B6/02—Compression machines, plants or systems, with several condenser circuits arranged in parallel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B6/00—Compression machines, plants or systems, with several condenser circuits
    • F25B6/04—Compression machines, plants or systems, with several condenser circuits arranged in series
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B9/00—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B9/00—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point
    • F25B9/002—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant
    • F25B9/008—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant the refrigerant being carbon dioxide
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2309/00—Gas cycle refrigeration machines
    • F25B2309/06—Compression machines, plants or systems characterised by the refrigerant being carbon dioxide
    • F25B2309/061—Compression machines, plants or systems characterised by the refrigerant being carbon dioxide with cycle highest pressure above the supercritical pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2500/00—Problems to be solved
    • F25B2500/18—Optimization, e.g. high integration of refrigeration components

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Other Air-Conditioning Systems (AREA)
  • Compression-Type Refrigeration Machines With Reversible Cycles (AREA)
  • External Artificial Organs (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Abstract

The present invention refers to a method of operating an assembly (1) of heat exchangers (2) for subcritical and transcritical conditions, by initially arranging at least two heat exchangers (2) in parallel for the subcritical condition.

Description

The assembly of operation heat exchanger is used for subcritical state and strides the method for critical condition and the assembly of heat exchanger
Technical field
The present invention relates to through initial at least two parallel layouts of heat exchanger are used for subcritical state, the assembly of operation heat exchanger is used for subcritical state and strides the method for critical condition, and relates to the assembly of heat exchanger.
Background technology
In traditional refrigeration system, from the heat release of refrigerant condensation based on refrigerant.Stationary temperature is critical point during condensation.The component definition of operation heat exchanger is a sub-critical mode below critical point.Previously known is arranged heat exchanger is parallel in this sub-critical mode.
Yet, in the heat pump and freeze applications that utilize CO2 as refrigerant, exist striding critical conduction mode, promptly more than critical point, and the needs of below critical point, operating.Utilizing CO2 is known in the art as the critical refrigeration system of striding of refrigerant.The critical-temperature of CO2 is that 31.0 ℃ and critical pressure are 73.8 crust.Between liquid and steam, can not find tangible difference under the higher temperature and pressure, and CO2 it is said in so-called shooting flow body region.The hot state that is used for these two kinds of operator schemes is significantly different.Cold side during striding critical conduction mode, the flow rate that typically is salt solution or water is far below during sub-critical mode.Aspect hot, the process of the hot side of refrigerant is also very different.In striding critical conduction mode, when closely near narrow point and outlet, require big temperature to descend.This requires two kinds of different designs of heat exchanger together, with can be with optimum way operating system.
The temperature difference that consideration needs in heat exchanger, is used for will being about 20 ℃ ambient temperature based on the upper limit of the heat release of the condensation of CO2 by promptly about 10 ℃.Below the temperature, CO2 rests on below the critical point and refrigeration system is operated in sub-critical mode at this.For the refrigeration system that utilizes at the supermarket, ambient temperature will be above 20 ℃ during the most summer in the world.In these temperature, the cooling of CO2 is single-phase cooling, i.e. gas cooled.More than critical point, and operate in striding critical conduction mode by refrigeration system in the high-pressure side of system for CO2.
The efficient of refrigeration system and cooling capacity are lower than in striding critical operation in subcritical operation.The significant drawbacks of known CO2 refrigeration system is in the ambient temperature that is higher than about 20 ℃ raising, and when promptly in fact expecting high-performance, they have the performance of reduction.A target of the present invention provides the critical refrigeration system of striding that has during striding critical operation improved performance.
Summary of the invention
A target of the present invention is the solution of setting up the problem of the opposition requirement of the design of heat exchanger that is used for gas cooler and condenser.Those skilled in the art can utilize a plurality of heat exchangers in system, rather than seek the design be used for typically by the subcritical state decision and then it be used to stride the heat exchanger of critical operation.
According to a first aspect of the invention; These targets realize through following: at least one heat exchanger is being striden critical condition and other heat exchanger arranged; And import and outlet are arranged in the opposed end of assembly; And through in first heat exchanger back with between per two heat exchangers, close and connect first pipeline of said import to first conduit of each heat exchanger; And, heat exchanger is switched to arranged from parallel the layout through between other heat exchanger, closing said second pipeline that exports to second conduit of each heat exchanger of connection.
This method is included in to utilize parallel a plurality of heat exchangers during the condensation and during striding critical operation, become then with serial or with serial and parallel uniting utilizes them.
Because hot length with conduct heat to increase and thereby the outlet temperature of refrigerant can reduce, so this has improved system effectiveness considerably in striding critical conduction mode.
In addition; Through in first heat exchanger back with between per two heat exchangers, close and connect first pipeline of said import to first conduit of each heat exchanger; And, heat exchanger is switched to arranged from parallel the layout through between other heat exchanger, closing said second pipeline that exports to second conduit of each heat exchanger of connection.
Through being provided for two kinds of basic liquid mediums,, each loop is arranged that from parallel switching to arranged is advantage such as the dual loop of the heat transfer between refrigerant and the salt solution for said heat exchanger.
Increased flexibility and made it possible to through this sub-critical mode and the performance of striding the critical conduction mode optimization system.
Another aspect of the present invention is the assembly of heat exchanger; It has the import of the opposed end of assembly and outlet, be connected to said import and be connected to each heat exchanger first conduit first pipeline and be connected to second pipeline of second conduit of said outlet and each heat exchanger; It is characterized in that; Valve is arranged in first pipeline in first heat exchanger back and between per two heat exchangers; And valve is arranged in second pipeline between other heat exchanger, and wherein, all valves are shown in an open position the parallel heat exchanger of arranging and the heat exchanger of arranged is in the close position all valves.
Description of drawings
Of the present invention these now will be with others through describing in more detail with reference to the accompanying drawing that currently preferred embodiment of the present invention is shown.
Fig. 1 a illustrates according to the present invention the sketch map according to the assembly of the first parallel heat exchanger of arranging mode of operation.
Fig. 1 b illustrates the temperature/position table that is used for according to the mode of operation of Fig. 1 a.
Fig. 2 a illustrates according to the present invention the sketch map according to the assembly of the heat exchanger of the second arranged mode of operation.
Fig. 2 b illustrates the temperature/position table that is used for according to the mode of operation of Fig. 2 a.
The specific embodiment
Fig. 1 a and Fig. 2 a illustrate the assembly 1 of heat exchanger 2.Heat exchanger 2 respectively has and is used for two kinds of basic liquid mediums, such as the dual loop of the heat transfer between refrigerant and the salt solution.Yet the present invention also is available in the heat exchanger that only has a kind of liquid medium.The assembly 1 of heat exchanger 2 have the opposed end of assembly 1 for example from the import A of the compressor reducer (not shown) in the cryogen circuit with for example arrive the outlet B of expansion valve (not shown).Assembly 1 has the respective inlets C that is used for brine loop and outlet D at the opposed end of assembly 1.In addition, assembly 1 has first pipeline 4 of first conduit 5 that is connected to said import A and is connected to each heat exchanger 2 and is connected to said outlet B and second pipeline 6 of second conduit 7 of each heat exchanger 2.And; Valve 3 is arranged in first pipeline 4, and in first heat exchanger 2 back and between per two heat exchangers 2, and valve 3 is arranged in second pipeline 6 between other heat exchanger 2; Wherein shown in Fig. 1 a; The parallel heat exchanger of arranging 2 is shown in an open position all valves 3, and shown in Fig. 2 a, the heat exchanger 2 of arranged is in the close position all valves 3.
In Fig. 1 a, heat exchanger 2 parallel layouts are used for subcritical state, promptly are in the following temperature of condensing state of refrigerant.Heat transfer is shown in Fig. 1 b, and wherein the temperature from import A to outlet B of the corresponding refrigerant of upper curve descends, and this refrigerant has about stationary temperature during condensation, and the temperature of the corresponding salt solution of lower curve from import C to outlet D rises.In Fig. 2 a, heat exchanger 2 is being striden critical condition, promptly is in the above temperature of condensing state of refrigerant, each other arranged.Heat transfer is shown in Fig. 2 b, and wherein the temperature from import A to outlet B of the corresponding refrigerant of upper curve descends, and the temperature from import C to outlet D of the corresponding salt solution of lower curve rises.Heat exchanger 2 switches to arranged through shut off valve 3 from parallel the layout, valve 3 arranged alternate in first pipeline 4 of first conduit 5 that is connected to each heat exchanger 2 between per two heat exchangers and be arranged in second pipeline 6 of second conduit 7 that is connected to each heat exchanger 2 between other heat exchanger 2.
The brine loop (not shown) has the respective line 8 and pipeline 9 that is communicated with import C and outlet D respectively, and valve 10.Brine loop can likewise switch to arranged from parallel the layout.Valve 10 is arranged in the pipeline 8; With reference to first heat exchanger 2 back of import C and between per two heat exchangers 2; And valve 10 is arranged in second pipeline 9 between other heat exchanger 2, and wherein shown in Fig. 1 a, the parallel heat exchanger of arranging 2 is shown in an open position all valves 10; And shown in Fig. 2 a, the heat exchanger 2 of arranged is in the close position all valves 10.
Those skilled in the art recognize that the present invention never is subject to preferred embodiment mentioned above.On the contrary, within the scope of the appended claims many modifications and modification is possible.For example, can operate only loop of dual loop heat exchanger according to the present invention.

Claims (4)

1. one kind through at first being used for subcritical state with the parallel layout of at least two heat exchangers (2); The assembly (1) of operation heat exchanger (2) is used for subcritical state and the method for striding critical condition; It is characterized in that; At least one heat exchanger (2) is being striden critical condition and other heat exchanger arranged; And import (A) and outlet (B) are arranged in the opposed end of said assembly (1); And through in first heat exchanger (2) back with between per two heat exchangers (2), close and connect first pipeline (4) of said import (A), and connect second pipeline (6) of said outlet (B), said heat exchanger (2) is switched to arranged from parallel the layout to second conduit (7) of each heat exchanger (2) through between other heat exchanger, closing to first conduit (5) of each heat exchanger (2).
2. method according to claim 1, for said heat exchanger (2) is provided for two kinds of basic liquid mediums, the dual loop such as the heat transfer between refrigerant and the salt solution is characterized in that, each loop is switched to arranged from parallel the layout.
3. according to each the described method in claim 1 or 2, it is characterized in that, striding critical condition all heat exchangers (2) arranged.
4. the assembly (1) of a heat exchanger (2); Said assembly (1) have the import (A) of the opposed end of said assembly (1) and the outlet (B), be connected to said import (A) and be connected to each heat exchanger (2) first conduit (5) first pipeline (4) and be connected to said outlet (B) and second pipeline (6) of second conduit (7) of each heat exchanger (2); It is characterized in that; Valve (3) is arranged in said first pipeline (4) in first heat exchanger (2) back and between per two heat exchangers (2); And valve (3) is arranged in said second pipeline (6) between other heat exchanger (2); Wherein, the parallel said heat exchanger of arranging (2) is shown in an open position all valves (3) and the said heat exchanger (2) of arranged is in the close position all valves (3).
CN2010800301916A 2009-06-30 2010-06-23 Method of operating an assembly of heat exchangers for subcritical and transcritical conditions, and an assembly of heat exchangers Pending CN102472588A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
SE0950507-4 2009-06-30
SE0950507A SE533859C2 (en) 2009-06-30 2009-06-30 Method for operating a system of heat exchangers for subcritical and transcritical states, as well as a system of heat exchangers
PCT/SE2010/050717 WO2011002401A2 (en) 2009-06-30 2010-06-23 Method of operating an assembly of heat exchangers for subcritical and transcritical conditions, and an assembly of heat exchangers

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Publication Number Publication Date
CN102472588A true CN102472588A (en) 2012-05-23

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CN2010800301916A Pending CN102472588A (en) 2009-06-30 2010-06-23 Method of operating an assembly of heat exchangers for subcritical and transcritical conditions, and an assembly of heat exchangers

Country Status (9)

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US (1) US20120132399A1 (en)
EP (1) EP2449330A2 (en)
JP (1) JP2012532303A (en)
KR (1) KR20120036899A (en)
CN (1) CN102472588A (en)
CA (1) CA2765853A1 (en)
RU (1) RU2012103008A (en)
SE (1) SE533859C2 (en)
WO (1) WO2011002401A2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107631512A (en) * 2017-09-04 2018-01-26 广东美的暖通设备有限公司 Multiple on-line system
CN111336707A (en) * 2020-02-29 2020-06-26 同济大学 Carbon dioxide heat pump heating system with topologic homoembryo circulation

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013160929A1 (en) * 2012-04-23 2013-10-31 三菱電機株式会社 Refrigeration cycle system

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10170081A (en) * 1996-12-11 1998-06-26 Toshiba Corp Air conditioner
JP2006097978A (en) * 2004-09-29 2006-04-13 Denso Corp Refrigerating cycle
CN101137872A (en) * 2005-03-14 2008-03-05 约克国际公司 Hvac system with powered subcooler
CN101354198A (en) * 2007-07-23 2009-01-28 Lg电子株式会社 Air conditioning system

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10267494A (en) * 1997-03-25 1998-10-09 Mitsubishi Electric Corp Cooler

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10170081A (en) * 1996-12-11 1998-06-26 Toshiba Corp Air conditioner
JP2006097978A (en) * 2004-09-29 2006-04-13 Denso Corp Refrigerating cycle
CN101137872A (en) * 2005-03-14 2008-03-05 约克国际公司 Hvac system with powered subcooler
CN101354198A (en) * 2007-07-23 2009-01-28 Lg电子株式会社 Air conditioning system

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107631512A (en) * 2017-09-04 2018-01-26 广东美的暖通设备有限公司 Multiple on-line system
CN111336707A (en) * 2020-02-29 2020-06-26 同济大学 Carbon dioxide heat pump heating system with topologic homoembryo circulation
CN111336707B (en) * 2020-02-29 2021-09-03 同济大学 Carbon dioxide heat pump heating system with topologic homoembryo circulation

Also Published As

Publication number Publication date
SE533859C2 (en) 2011-02-08
CA2765853A1 (en) 2011-01-06
RU2012103008A (en) 2013-08-10
KR20120036899A (en) 2012-04-18
EP2449330A2 (en) 2012-05-09
WO2011002401A3 (en) 2011-06-09
JP2012532303A (en) 2012-12-13
US20120132399A1 (en) 2012-05-31
WO2011002401A2 (en) 2011-01-06
SE0950507A1 (en) 2010-12-31

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Application publication date: 20120523