WO2000037862A1 - Heat exchanger - Google Patents

Heat exchanger Download PDF

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Publication number
WO2000037862A1
WO2000037862A1 PCT/SE1999/002308 SE9902308W WO0037862A1 WO 2000037862 A1 WO2000037862 A1 WO 2000037862A1 SE 9902308 W SE9902308 W SE 9902308W WO 0037862 A1 WO0037862 A1 WO 0037862A1
Authority
WO
WIPO (PCT)
Prior art keywords
tube
wall
heat exchanger
bore hole
walls
Prior art date
Application number
PCT/SE1999/002308
Other languages
French (fr)
Inventor
Bertil Forsman
Original Assignee
Bertil Forsman
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 Bertil Forsman filed Critical Bertil Forsman
Priority to AU20183/00A priority Critical patent/AU2018300A/en
Publication of WO2000037862A1 publication Critical patent/WO2000037862A1/en

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24T—GEOTHERMAL COLLECTORS; GEOTHERMAL SYSTEMS
    • F24T10/00—Geothermal collectors
    • F24T10/10—Geothermal collectors with circulation of working fluids through underground channels, the working fluids not coming into direct contact with the ground
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/10—Geothermal energy

Definitions

  • the present invention relates to a heat exchanger to be introduced into a bore hole in a rock, loose earth or the similar as well as a method for introducing such a heat exchanger in a bore hole.
  • SE-B-447 844 discloses a heat exchanger having two or more tubes which are brought to a certain abutment against a wall of a bore hole by means of expanding elements. At such a heat exchanger only a part of the surface of the tubes are brought to abutment against the wall of the bore hole which leads to that a great part of the surfaces of the tubes still are influenced by the heat transfer resistance of the surrounding water.
  • the object of the present invention is to obtain a heat exchanger of the type mentioned above of which one tube wall is placed in abutment to the wall of the bore hole along substantially all the periphery of the bore hole.
  • a heat exchanger to be introduced into a bore hole in rock, loose earth and the similar which is characterized by a first tube having a circular cross-section and a second tube having a first wall extending substantially around the whole periphery of the first tube, a second wall extending outside the first wall at some distance from this and two end walls which connect neighbouring ends of the first and second walls to each other, which second tube is made of a flexible material whereby a pressure introduced in the space between the first and second walls of the second tube leads to that the distance between these increases, and of a device to connect the bottom end of the first tube with the bottom end of the second tube in such a way that a fluid can flow between the tubes.
  • a layer of a heat insulating material attached to the outer side of the first tube and the first tube is made of a flexible material, as well.
  • the invention further relates to a method for introducing, into a bore hole in rock, loose earth material or the similar, a heat exchanger comprising a first tube having a circular cross-section and a second tube having a first wall extending substantially around the whole periphery of the first tube, a second wall extending outside the first wall at some distance from this and two end walls which connect neighbouring ends of the first and second walls to each other, which second tube is made of a flexible material, whereby the method is characterized in that the heat exchanger is introduced into the bore hole, whereupon the space between the first and second walls of the second tube is put under pressure in such a way that the second wall of the second tube moves from the first wall and is brought to abutment against the wall of the bore hole along substantially all its periphery whereby the dimension of the bore hole is so selected that the first wall of the second tube substantially surrounds the first tube, these increases.
  • the first and second tubes are delivered preferably in a composed unit but also as sole components and be brought together in connection with the introduction of the heat exchanger in a bore hole.
  • FIG. 1 shows schematically an embodiment of the heat exchanger according to the invention introduced into a bore hole, in a perspective view
  • FIG. 2 shows a cross-section of the heat exchanger of Fig. 1 in a mounting position
  • FIG. 3 shows a similar view as the one of Fig. 2 but having the heat exchanger in use position. Description of one embodiment
  • the heat exchanger of the present invention comprises a first inner tube 1 having a circular cross-section, which tube on its outer side is provided with a layer 2 of a heat insulating material.
  • the first tube 1 is surrounded by a second tube 3 which has two walls which runs almost circularly in a peripheral direction, an inner first wall 4, and a outer second wall 5 and two end walls 6, 7 which connect neighbouring ends of the first and second walls 5, 6.
  • the tubes 1 and 3 can be made of such polymer materials which are commonly used for heat exchanging tubes intended to be brought into bore holes and may e.g., be made by injection moulding.
  • the outer wall 5 of the second tube 3 is present at some distance from the wall of a bore hole 8 and the combination of tubes 1, 3 described can without difficulty be introduced into the bore hole.
  • the heat exchanger has a end part, not shown, which is attached to the bottom ends of the tubes 1 and 3 and allows for flow of fluid between the tubes 1 and 3.
  • the end part can be made of a form moulded polymer material being welded to the ends of the tubes 1, 3.
  • the heat exchanger is shown in a use position in which a heat carrier under pressure flows through the tubes 1 and 3.
  • the heat carrier flows preferably down through the outer tube 3 and up through the inner tube 1 but the opposite flow pattern is possible, as well.
  • the tube 3 is made of a flexible material the bringing of the tube under pressure will lead to that the inner and outer walls 4, 5 tend to move from each other, which leads to that the outer wall 5 will be brought to abutment against the wall of the bore hole 8.
  • the deformation of the tube 3 further leads to that the end walls 6 and 7 moves away from each other.
  • the relative dimensions between the diameter of the bore hole and the dimension of the tube 3 shall be such that the tube 3 surrounds the major part of the inner tube 1 even after the expansion due to the pressurizing.
  • the tube 3 should thus in its expanded position surround the tube in an angle exceeding 300 degrees.
  • the ends of the tubes 1 and 3 situated above ground are by means of a none shown connecting joint connected to conventional tubes.
  • the tubes 1 and 3 may either be delivered as a unit or a sole components which are mounted just prior to the introduction in a bore hole. As the tube 3 is flexible the tube 1 can easily be introduced therein or the abutting end edges 6, 7 of the tube 3 be separated from each other and the tube 1 can then be introduced between the separated edges.
  • the tube 3 will, due to its elasticity to return to its original configuration shown in figure 2 when the pressure is let whereupon the heat exchanger easily can be withdrawn from the bore hole.
  • the tube 3 can be brought to subpressure to facilitate the removal to the mounting configuration.
  • the high yield of the heat exchanger described makes it possible to use bore holes having a smaller depth compared to the bore hole dimensions which are necessary at conventional heat exchangers.
  • the cost for boring holes in the ground is a large part of the installation cost of a heat exchanging pump of a house those small bore hole dimensions which can be used at a heat exchanger according to the present invention leads to markedly reduced cost for such an installation.

Landscapes

  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Abstract

The present invention relates to heat exchanger to be introduced in a bore hole in rock, loose earth or the similar. According to the invention the heat exchanger comprises a first tube (1) having a circular cross-section and a second tube (3) having a first wall (4) extending substantially around the whole periphery of the first tube (1), a seocnd wall (5) extending outside the first wall at some distance from this and two end walls (6, 7) which connect neightbouring ends of the first and second walls to each other, which second tube is made of a flexible material whereby a pressure introduced in the space between the first and second walls of the second tube leads to that the distance between these increases, and of a device to connect the bottom end of the first tube with the bottom end of the second tube in such a way that a fluid can flow between the tubes.

Description

TITLE
HEAT EXCHANGER
DESCRIPTION Technical field
The present invention relates to a heat exchanger to be introduced into a bore hole in a rock, loose earth or the similar as well as a method for introducing such a heat exchanger in a bore hole.
Background of the invention
It has turned out that heat exchanger in bore holes, e.g., for extracting heat by means of a heat pump or for cooling work better if the heat exchange can take place without any influence from the heat transfer resistance which exists in water between the tubes present in the heat exchanger and the wall of the bore hole. SE-B-447 844 discloses a heat exchanger having two or more tubes which are brought to a certain abutment against a wall of a bore hole by means of expanding elements. At such a heat exchanger only a part of the surface of the tubes are brought to abutment against the wall of the bore hole which leads to that a great part of the surfaces of the tubes still are influenced by the heat transfer resistance of the surrounding water.
The object of the present invention is to obtain a heat exchanger of the type mentioned above of which one tube wall is placed in abutment to the wall of the bore hole along substantially all the periphery of the bore hole.
Summary of the invention
This object is achieved by means of a heat exchanger to be introduced into a bore hole in rock, loose earth and the similar which is characterized by a first tube having a circular cross-section and a second tube having a first wall extending substantially around the whole periphery of the first tube, a second wall extending outside the first wall at some distance from this and two end walls which connect neighbouring ends of the first and second walls to each other, which second tube is made of a flexible material whereby a pressure introduced in the space between the first and second walls of the second tube leads to that the distance between these increases, and of a device to connect the bottom end of the first tube with the bottom end of the second tube in such a way that a fluid can flow between the tubes.
In a preferred embodiment there is a layer of a heat insulating material attached to the outer side of the first tube and the first tube is made of a flexible material, as well.
The invention further relates to a method for introducing, into a bore hole in rock, loose earth material or the similar, a heat exchanger comprising a first tube having a circular cross-section and a second tube having a first wall extending substantially around the whole periphery of the first tube, a second wall extending outside the first wall at some distance from this and two end walls which connect neighbouring ends of the first and second walls to each other, which second tube is made of a flexible material, whereby the method is characterized in that the heat exchanger is introduced into the bore hole, whereupon the space between the first and second walls of the second tube is put under pressure in such a way that the second wall of the second tube moves from the first wall and is brought to abutment against the wall of the bore hole along substantially all its periphery whereby the dimension of the bore hole is so selected that the first wall of the second tube substantially surrounds the first tube, these increases.
The first and second tubes are delivered preferably in a composed unit but also as sole components and be brought together in connection with the introduction of the heat exchanger in a bore hole.
Figure legends
The invention will now be described with reference to the attached figures, of which
FIG. 1 shows schematically an embodiment of the heat exchanger according to the invention introduced into a bore hole, in a perspective view;
FIG. 2 shows a cross-section of the heat exchanger of Fig. 1 in a mounting position; and FIG. 3 shows a similar view as the one of Fig. 2 but having the heat exchanger in use position. Description of one embodiment
The heat exchanger of the present invention comprises a first inner tube 1 having a circular cross-section, which tube on its outer side is provided with a layer 2 of a heat insulating material. The first tube 1 is surrounded by a second tube 3 which has two walls which runs almost circularly in a peripheral direction, an inner first wall 4, and a outer second wall 5 and two end walls 6, 7 which connect neighbouring ends of the first and second walls 5, 6. The tubes 1 and 3 can be made of such polymer materials which are commonly used for heat exchanging tubes intended to be brought into bore holes and may e.g., be made by injection moulding.
In the mounting position shown in figures 1 and 2 the outer wall 5 of the second tube 3 is present at some distance from the wall of a bore hole 8 and the combination of tubes 1, 3 described can without difficulty be introduced into the bore hole. In its bottom end the heat exchanger has a end part, not shown, which is attached to the bottom ends of the tubes 1 and 3 and allows for flow of fluid between the tubes 1 and 3. The end part can be made of a form moulded polymer material being welded to the ends of the tubes 1, 3.
In figure 3 the heat exchanger is shown in a use position in which a heat carrier under pressure flows through the tubes 1 and 3. The heat carrier flows preferably down through the outer tube 3 and up through the inner tube 1 but the opposite flow pattern is possible, as well. As the tube 3 is made of a flexible material the bringing of the tube under pressure will lead to that the inner and outer walls 4, 5 tend to move from each other, which leads to that the outer wall 5 will be brought to abutment against the wall of the bore hole 8. The deformation of the tube 3 further leads to that the end walls 6 and 7 moves away from each other. The relative dimensions between the diameter of the bore hole and the dimension of the tube 3 shall be such that the tube 3 surrounds the major part of the inner tube 1 even after the expansion due to the pressurizing. The tube 3 should thus in its expanded position surround the tube in an angle exceeding 300 degrees. The ends of the tubes 1 and 3 situated above ground are by means of a none shown connecting joint connected to conventional tubes.
The tubes 1 and 3 may either be delivered as a unit or a sole components which are mounted just prior to the introduction in a bore hole. As the tube 3 is flexible the tube 1 can easily be introduced therein or the abutting end edges 6, 7 of the tube 3 be separated from each other and the tube 1 can then be introduced between the separated edges.
If one wants to withdraw the heat exchanger from the bore hole the tube 3 will, due to its elasticity to return to its original configuration shown in figure 2 when the pressure is let whereupon the heat exchanger easily can be withdrawn from the bore hole. Optionally, the tube 3 can be brought to subpressure to facilitate the removal to the mounting configuration.
In the use position the whole of the outer wall 5 abuts the wall of the bore hole 8 and it extends further over the major part of the periphery of the bore hole 8. By means of the invention it is obtained a very efficient heat transfer from the surrounding rock or earth to the heat or cooling media flowing in the outer tube 3. All the heat transfer resistance which is obtained by water present in a bore holeat conventional heat exchanger arranged in bore hole has been eliminated at the heat exchanger of the present invention. The heat exchanger of the present invention thus shows a high yield unregarded if it is used to extract heat or cold from the surrounding rock or surrounding earth.
The high yield of the heat exchanger described makes it possible to use bore holes having a smaller depth compared to the bore hole dimensions which are necessary at conventional heat exchangers. As the cost for boring holes in the ground is a large part of the installation cost of a heat exchanging pump of a house those small bore hole dimensions which can be used at a heat exchanger according to the present invention leads to markedly reduced cost for such an installation.

Claims

1. Heat exchanger to be introduced in a bore hole in rock, loose earth or the similar, characterized by a first tube (1) having a circular cross-section and a second tube (3) having a first wall (4) extending substantially around the whole periphery of the first tube (1), a second wall (5) extending outside the first wall at some distance from this and two end walls (6, 7) which connect neighbouring ends of the first and second walls to each other, which second tube is made of a flexible material whereby a pressure introduced in the space between the first and second walls of the second tube leads to that the distance between these increases, and of a device to connect the bottom end of the first tube with the bottom end of the second tube in such a way that a fluid can flow between the tubes.
2. Heat exchanger according to claim 1, characterized in that a layer (2) of a heat insulating material is provided on the outer side of the first tube (1).
3. Heat exchanger according to claim 1 or 2, characterized in that the first tube (1) is manufactured in a flexible material, as well.
4. Method for applying a heat exchanger in a bore hole (8) in rock or loose earth material or the similar, comprising a first tube (1) having a circular cross-section and a second tube (3) having a first wall (4) extending substantially around the whole periphery of the first tube, a second wall (5) extending outside the first wall at some distance from this and two end walls (6, 7) which connect neighbouring ends of the first and second walls to each other, which second tube is made of a flexible material, characterized in that the heat exchanger is introduced into the bore hole (8), whereupon the space between the first and second walls (4, 5) of the second tube (3) is brought under pressure in such a way that the second wall (5) of the second tube moves from the first wall (4) and is brought to abutment against the wall of the bore hole (8) along substantially all its periphery whereby the dimension of the bore hole (8) is so selected that the first wall of the second tube (3) substantially surrounds the first tube (1).
5. Method according to claim 4, characterized in that the first and second tubes (1, 3) are delivered as a composed unit.
6. Method according to claim4, characterized in that the first and second tubes (1, 3) are delivered as sole components and are brought together in connection with the introduction of the heat exchanger in a bore hole (8).
PCT/SE1999/002308 1998-12-09 1999-12-09 Heat exchanger WO2000037862A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU20183/00A AU2018300A (en) 1998-12-09 1999-12-09 Heat exchanger

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9804266A SE513267C2 (en) 1998-12-09 1998-12-09 Heat exchanger for placement in boreholes and ways of applying heat exchanger
SE9804266-6 1998-12-09

Publications (1)

Publication Number Publication Date
WO2000037862A1 true WO2000037862A1 (en) 2000-06-29

Family

ID=20413606

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE1999/002308 WO2000037862A1 (en) 1998-12-09 1999-12-09 Heat exchanger

Country Status (3)

Country Link
AU (1) AU2018300A (en)
SE (1) SE513267C2 (en)
WO (1) WO2000037862A1 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100407673B1 (en) * 2000-12-29 2003-12-01 박혜서 An air conditioning system using the heat of the earth and method of constructing a large heat-exchanging pipe
WO2013185083A3 (en) * 2012-06-07 2014-06-26 Braun Intertec Geothermal, Llc Ground heat exchange processes and equipment
US20150068740A1 (en) * 2012-05-14 2015-03-12 Broder Ag Coaxial ground heat exchanger and method for installing said ground heat exchanger in the ground
GB2549832A (en) * 2016-03-08 2017-11-01 Henderson William Geothermal power system
JP6260977B1 (en) * 2016-10-26 2018-01-17 株式会社エコ・プランナー Ground heat exchange device and method for constructing liquid storage tank for ground heat exchange device
WO2020085990A1 (en) * 2018-10-26 2020-04-30 Rototec Ab Thermal well heat carrier transport system and method for installation of the same

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2748727A1 (en) * 1976-11-01 1978-05-03 Ove Bertil Platell METHOD AND DEVICE FOR STORING THERMAL ENERGY, SUCH AS SOLAR HEAT, FOR EXAMPLE
DE3015723A1 (en) * 1980-04-24 1981-10-29 Aeroaqua AG, Oberwil Ground heat absorber for heat pump - has foil hose of corrosion-proof material surrounding rinsing jacket
CH658513A5 (en) * 1985-04-29 1986-11-14 Anton Broder Method and device for exchanging heat between a storage body which is solid, or contains gas or liquid
US5339890A (en) * 1993-02-08 1994-08-23 Climate Master, Inc. Ground source heat pump system comprising modular subterranean heat exchange units with concentric conduits
DE19519993A1 (en) * 1995-05-24 1996-11-28 Ver Energiewerke Ag Geothermal probe

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2748727A1 (en) * 1976-11-01 1978-05-03 Ove Bertil Platell METHOD AND DEVICE FOR STORING THERMAL ENERGY, SUCH AS SOLAR HEAT, FOR EXAMPLE
DE3015723A1 (en) * 1980-04-24 1981-10-29 Aeroaqua AG, Oberwil Ground heat absorber for heat pump - has foil hose of corrosion-proof material surrounding rinsing jacket
CH658513A5 (en) * 1985-04-29 1986-11-14 Anton Broder Method and device for exchanging heat between a storage body which is solid, or contains gas or liquid
US5339890A (en) * 1993-02-08 1994-08-23 Climate Master, Inc. Ground source heat pump system comprising modular subterranean heat exchange units with concentric conduits
DE19519993A1 (en) * 1995-05-24 1996-11-28 Ver Energiewerke Ag Geothermal probe

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100407673B1 (en) * 2000-12-29 2003-12-01 박혜서 An air conditioning system using the heat of the earth and method of constructing a large heat-exchanging pipe
US20150068740A1 (en) * 2012-05-14 2015-03-12 Broder Ag Coaxial ground heat exchanger and method for installing said ground heat exchanger in the ground
JP2015517643A (en) * 2012-05-14 2015-06-22 ブローダー アクチエンゲゼルシャフトＢｒｏｄｅｒ ＡＧ Coaxial underground heat exchanger and method of installing such a coaxial underground heat exchanger underground
US10767903B2 (en) * 2012-05-14 2020-09-08 Broder Ag Coaxial ground heat exchanger and method for installing said ground heat exchanger in the ground
WO2013185083A3 (en) * 2012-06-07 2014-06-26 Braun Intertec Geothermal, Llc Ground heat exchange processes and equipment
US9157666B2 (en) 2012-06-07 2015-10-13 Braun Intertec Geothermal, Llc Ground heat exchange processes and equipment
GB2549832A (en) * 2016-03-08 2017-11-01 Henderson William Geothermal power system
CN109073326A (en) * 2016-10-26 2018-12-21 日商环保规划股份有限公司 Geothermal heat exchanger
WO2018079463A1 (en) * 2016-10-26 2018-05-03 株式会社エコ・プランナー Underground heat exchanger
TWI668402B (en) * 2016-10-26 2019-08-11 日商環保規劃股份有限公司 Geothermal exchange device
JP6260977B1 (en) * 2016-10-26 2018-01-17 株式会社エコ・プランナー Ground heat exchange device and method for constructing liquid storage tank for ground heat exchange device
US10871310B2 (en) 2016-10-26 2020-12-22 Eco-Planner Co., Ltd. Underground heat exchanger
CN113503758A (en) * 2016-10-26 2021-10-15 日商环保规划股份有限公司 Geothermal heat exchanger
CN113503758B (en) * 2016-10-26 2023-06-09 日商环保规划股份有限公司 Geothermal exchange device
WO2020085990A1 (en) * 2018-10-26 2020-04-30 Rototec Ab Thermal well heat carrier transport system and method for installation of the same
EP3870908A4 (en) * 2018-10-26 2021-12-08 Rototec AB Thermal well heat carrier transport system and method for installation of the same
US11619117B2 (en) 2018-10-26 2023-04-04 Rototec Ab Thermal well heat carrier transport system and method for installation of the same

Also Published As

Publication number Publication date
SE9804266L (en) 2000-06-10
AU2018300A (en) 2000-07-12
SE513267C2 (en) 2000-08-14
SE9804266D0 (en) 1998-12-09

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