EP2219001A1 - Tube ondulé doté d'une section transversale elliptique - Google Patents

Tube ondulé doté d'une section transversale elliptique Download PDF

Info

Publication number
EP2219001A1
EP2219001A1 EP09290111A EP09290111A EP2219001A1 EP 2219001 A1 EP2219001 A1 EP 2219001A1 EP 09290111 A EP09290111 A EP 09290111A EP 09290111 A EP09290111 A EP 09290111A EP 2219001 A1 EP2219001 A1 EP 2219001A1
Authority
EP
European Patent Office
Prior art keywords
tube
corrugated tube
section
corrugated
cross
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.)
Withdrawn
Application number
EP09290111A
Other languages
German (de)
English (en)
Inventor
Martin Greiner
Olaf Mientkewitz
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.)
Alcatel Lucent SAS
Original Assignee
Alcatel Lucent SAS
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 Alcatel Lucent SAS filed Critical Alcatel Lucent SAS
Priority to EP09290111A priority Critical patent/EP2219001A1/fr
Publication of EP2219001A1 publication Critical patent/EP2219001A1/fr
Withdrawn legal-status Critical Current

Links

Images

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
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/08—Tubular elements crimped or corrugated in longitudinal 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
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/02—Tubular elements of cross-section which is non-circular
    • F28F1/06—Tubular elements of cross-section which is non-circular crimped or corrugated in cross-section

Definitions

  • the invention relates to a corrugated tube, with a corrugated inner surface and a corrugated outer surface.
  • tubes are used as a separation for different fluids within a container. Through the walls of the tube, heat is transferred between the fluids. Generally, a high efficiency of the heat transfer is preferred in order to keep the heat exchanging devices small and thus cost efficient.
  • the most simple tubes for this purpose are plain tubes; however plain tubes have a relatively low heat transfer efficiency. It is known to improve the heat transfer by using finned tubes.
  • the fins increase the surface of the tube on its outer side.
  • the heat transfer is asymmetric, with a higher heat transfer on the outer surface than on the inner, plain surface.
  • finned tubes are difficult to produce and quickly get dirty and exhibit fouling. Upon handling and installation, the fins can easily get damaged, and the finned tubes are relatively stiff and therefore difficult to bend during installation.
  • corrugated tubes with a circular cross-section to increase the heat transfer.
  • the corrugation increases the surface area as compared to plain tubes. Further, the corrugated inner and outer surface helps to make fluid flow turbulent, which also improves the heat transfer.
  • Corrugated tubes can be furnished with good flexibility for simple handling and installation. However, it has been recognized by the inventors that such corrugated tubes exhibit local areas of low heat transfer in practice, what decreases the overall heat transfer efficiency.
  • corrugated tube as introduced in the beginning, characterized in that the outer cross section of the corrugated tube is of elliptical or substantially elliptical shape.
  • the inventive tube shape allows to direct an oncoming fluid flow onto the outer tube surface in a way such that the fluid flow is basically parallel to the longer dimension of the elliptical outer cross-section. Then, the tube offers a relatively narrow, edge-shaped profile to the oncoming fluid, what results in a smooth fluid flow in the vicinity of the outer tube surface. Strong turbulences and areas with a low bypassing flow on the outer surface are reduced or even avoided.
  • An inventive tube with an oncoming flow in parallel to the longer side of the elliptical cross-section, results in a lower flow resistance as compared to a circular cross-section.
  • a turbulent flow Reynolds number > 10 5
  • a circular cross-sectional shape results in a drag coefficient of between 0.4 and 1.2
  • an inventive elliptical cross-sectional shape results in a drag coefficient of only 0.05 to 0.1, with a ratio of semi-minor to semi-major axis of 0.55.
  • the inventive elliptical outer cross-section offers a larger outer surface area as compared to a circular cross-section with respect to the same cross-sectional area, what also improves the heat transfer between a fluid flowing within the tube and fluid flowing around the tube.
  • the corrugated shape also helps to increase the flexibility of the tube and thus facilitates handling and installation. Moreover, as compared to a plain tube, the surface area is also increased. Finally, the corrugated shape on the outer surface and on the inner surface helps to shift the flow in the vicinity of the tube from laminar to turbulent already at relatively low flow speeds; a turbulent flow is preferred due to its better heat transfer efficiency.
  • the cross-section of the inventive tube is taken in a plane perpendicular to the direction in which the tube extends.
  • the outer cross-section of the tube is non-circular, and at least substantially elliptical. In other words, the cross-sectional shape is round and elongated, in accordance with the invention. Small deviations from an exactly elliptical cross-section do not affect the benefits of the invention.
  • the aspect ratio i.e. the ratio of the largest diameter (corresponding to the semi-major axis) and the diameter perpendicular to the largest diameter (corresponding to the semi-minor axis) of the outer cross-section is preferably 1.2 or more, particularly preferably 1.5 or more.
  • the corrugations manifest in alternating bulges and depressions on the tube surface along the direction in which the tube extends. It is noted that the corrugations can be realized, in particular, by a spiral structure or a sequence of closed ring-shaped bulges.
  • the inner cross section of the corrugated tube is of elliptical or substantially elliptical shape.
  • the inner cross-section is non-circular, round and elongated in shape.
  • the aspect ratio i.e. the ratio of the largest diameter (corresponding to a semi-major axis) and the diameter perpendicular to the largest diameter (corresponding to a semi-minor axis) of the inner cross-section is preferably 1.2 or more, particularly preferably 1.5 or more.
  • the corrugated tube has a uniform wall thickness.
  • Such a tube is simple to manufacture, and the heat transfer is basically symmetrical on the outer and inner surface of the tube.
  • the corrugated tube is flexible. This simplifies handling and installation.
  • the tube can be bent, according to the invention, manually without tools.
  • the corrugated shape is particular suitable for a high flexibility.
  • the flexibility can also be influenced by choosing the tube material properly.
  • the corrugated tube is made of a sheet metal or a plastic material.
  • Sheet metal is a good heat conductor.
  • Plastic material is particularly simple to process and inexpensive, and can provide a good flexibility.
  • the ratio A/B of the semi-major axis A and the semi-minor axis B of the elliptical outer cross section is 1.2 or more, and preferably 1.5 or more. From these ratios on, the benefits as compared to a circular cross-section, become particularly significant. The above ratios are also preferred for an inner elliptical cross-section.
  • an inventive corrugated tube for transferring heat between a first fluid flowing within the corrugated tube along the direction in which the corrugated tube extends, and a second fluid flowing around the corrugated tube.
  • the efficiency of the heat transfer between the first and second fluid can be improved significantly as compared to conventional corrugated tubes with a circular cross-section.
  • the second fluid has an oncoming flow direction basically parallel to the semi-major axis of the elliptical outer cross section. In this orientation, the flow behaviour of the second fluid is particularly beneficial, and the heat transfer is particularly efficient.
  • the second fluid has an oncoming flow direction whose component perpendicular to the direction in which the tube extends is basically parallel to the semi-major axis of the elliptical outer cross section. This also results in a highly efficient heat transfer due to the large surface area presented in parallel to the flow direction.
  • the second fluid has an oncoming flow direction basically perpendicular to the direction in which the corrugated tube extends.
  • the second flow perpendicular to the direction in which the tube extends (“tube axis") quickly brings fresh second fluid to the tube wall.
  • the first fluid and/or the second fluid are in turbulent flow. Under turbulent flow conditions, the heat transfer is particularly efficient.
  • a preferred variant of the inventive use is characterized in that the corrugated tube is part of a solar thermal system.
  • a high heat transfer efficiency is desired in order to be able to make use of even small sunlight quantities.
  • Fig. 1a shows an inventive corrugated tube 1 in a cross-sectional view taken in parallel to a direction 2 in which the tube 1 extends.
  • the tube 1 is straight in the example shown, therefore the direction 2 can also be called the tube axis.
  • the tube 1 has a uniform wall thickness, wherein the wall thickness is neglected in Fig. 1 .
  • the corrugation of the tube 1 is along the direction 2.
  • the corrugated tube 1 comprises a sequence of bulges 3 and depressions 4.
  • the bulges 3 and depressions 4 are closed ring-shaped, with the ring plane perpendicular to the direction 2. Therefore, the outer cross-section of the tube 1 varies in its dimensions along the direction 2.
  • Fig. 1b shows the outer cross-sections of the tube 1 of Fig. 1a in plane AA, see cross-section 5a, and in plane BB, see cross-section 5b.
  • Planes AA, BB are perpendicular to the (local) direction 2 in which the tube 1 extends.
  • the outer cross-sections 5a, 5b are elliptical and concentric, with the cross-section 5a, taken at a bulge 3, being larger than the cross-section 5b, taken at a depression 4.
  • Fig. 2a shows another inventive corrugated tube 21 in a cross-sectional view taken in parallel to the direction 2 in which the tube 21 extends.
  • the tube 21 is straight, so direction 2 can also be called the tube axis.
  • the tube 21 has a uniform wall thickness, which is not detailed in the Fig. 2a .
  • the corrugation is along the direction 2 again.
  • the corrugated tube 21 is of spiral type, with a single bulge 22 winding around the center (compare arrow of direction 2) of the tube 21, compare the trace 23 of the bulge 22 (only shown for a top tube part). Therefore, the outer cross-section of the tube 21 does not vary in its dimensions along the direction 2, but only in its position.
  • Fig. 2b shows the outer cross-section of the tube 21 of Fig. 2a in a plane CC, see cross-section 5c, and in a plane DD, see cross-section 5d.
  • Planes CC, DD are perpendicular to the (local) direction 2 in which the tube 21 extends, and have a distance along direction 2 corresponding to half of a turn of the bulge 22 around the tube center.
  • the outer cross-sections 5c, 5d are both elliptic and of equal size, but they are somewhat shifted against each other.
  • the shift of the cross-sections 5c, 5d may help to establish a turbulent flow in the interior of the tube 21 even at relatively low flow speeds.
  • tubes 1, 21 in Figs. 1 a and 2a are shown with a straight extension, inventive tubes may also have bent (curved) shapes.
  • the tubes 1, 21 are made of a flexible material.
  • Fig. 3 shows an enlarged cross-sectional view of the tube 1 of Fig. 1a , namely the top left-side wall part.
  • the tube 1 has a uniform wall thickness W along the direction 2, wherein the wall thickness W is measured in a plane perpendicular to the direction 2 in which the tube 1 extends, and from the inner surface 31 to the outer surface 32 of the tube 1. Both the inner surface 31 and the outer surface 32 are corrugated.
  • Fig. 4 illustrates the orientation of an inventive tube 1 relative to the fluid flow.
  • the tube 1 is shown in a cross-sectional view, taken in a plane perpendicular to the direction in which the tube 1 extends. In parallel to said direction, i.e. perpendicular to the plane of the drawing of Fig. 4 , flows a first fluid in the interior 44 of the tube 1.
  • the interior 44 of the tube 1 is limited by its inner surface; in Fig. 4 , only the elliptical inner cross-section 41, shown with a dashed line, is visible.
  • the tube 1 flows a second fluid, compare oncoming flow 42.
  • the tube 1 is limited to the outside by its outer surface; in Fig. 4 , only the elliptical outer cross-section 43 is visible.
  • Fig. 4 shows the semi-major axis A and the semi-minor axis B of the outer cross-section 43.
  • the ratio A/B is here about 1.7.
  • the oncoming flow 42 is, with its component in the plane perpendicular to the (local) direction in which the tube 1 extends, in parallel to the semi-major axis A (note that a small angular deviation ⁇ , such as up to 10°, between said component of the oncoming flow 42 and the semi-major axis A would still be tolerable in accordance with the invention).
  • the tube 1 parts the oncoming flow 42 like a wedge, presenting only its narrower side to the oncoming flow 42, with the most protruding edge having the strongest curvature of the elliptic outer cross-section 43.
  • the flow of the second fluid around the tube 1 is smooth, and the tube 1 represents only a low flow resistance.
  • the heat exchange between the first fluid flowing in the interior 44 and the second fluid flowing around the tube 1 is very efficient then.
  • the oncoming flow 42 is further perpendicular to the direction in which the tube extends (note that this is an option with respect to the invention).
  • the first fluid and/or the second fluid may be a liquid, in particular water or water mixed with an antifreeze agent, or a gas, in particular air, dried air or dried nitrogen.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Geometry (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
EP09290111A 2009-02-13 2009-02-13 Tube ondulé doté d'une section transversale elliptique Withdrawn EP2219001A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP09290111A EP2219001A1 (fr) 2009-02-13 2009-02-13 Tube ondulé doté d'une section transversale elliptique

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP09290111A EP2219001A1 (fr) 2009-02-13 2009-02-13 Tube ondulé doté d'une section transversale elliptique

Publications (1)

Publication Number Publication Date
EP2219001A1 true EP2219001A1 (fr) 2010-08-18

Family

ID=40823451

Family Applications (1)

Application Number Title Priority Date Filing Date
EP09290111A Withdrawn EP2219001A1 (fr) 2009-02-13 2009-02-13 Tube ondulé doté d'une section transversale elliptique

Country Status (1)

Country Link
EP (1) EP2219001A1 (fr)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2693152A1 (fr) * 2012-08-03 2014-02-05 Tom Richards, Inc. Échangeur de chaleur ultra-pure en ligne
CN105387756A (zh) * 2015-11-25 2016-03-09 重庆市龙山金属材料有限公司 一种改良热交换增强空调
CN105387753A (zh) * 2015-11-25 2016-03-09 重庆市龙山金属材料有限公司 一种改良热交换增强散热器
CN105387750A (zh) * 2015-11-25 2016-03-09 重庆市龙山金属材料有限公司 一种热交换增强管
CN105387755A (zh) * 2015-11-25 2016-03-09 重庆祥吉机械制造有限公司 一种热交换增强散热器
CN105387508A (zh) * 2015-11-25 2016-03-09 重庆市龙山金属材料有限公司 一种改良热交换增强地暖
CN105387747A (zh) * 2015-11-25 2016-03-09 重庆市龙山金属材料有限公司 一种交叉椭圆截面及圆面热交换增强管
CN105387751A (zh) * 2015-11-25 2016-03-09 重庆祥吉机械制造有限公司 一种新型热交换增强热水器
CN105387760A (zh) * 2015-11-25 2016-03-09 重庆市龙山金属材料有限公司 一种热交换增强空调
CN105387749A (zh) * 2015-11-25 2016-03-09 重庆祥吉机械制造有限公司 一种新型热交换增强地暖
CN105465867A (zh) * 2015-11-25 2016-04-06 重庆市龙山金属材料有限公司 一种热交换增强地暖
CN110553531A (zh) * 2019-10-11 2019-12-10 上海东润换热设备制造有限公司 一种椭圆波节型换热器管束
CN110579122A (zh) * 2019-10-11 2019-12-17 上海东润换热设备制造有限公司 一种换热器

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB398154A (en) * 1930-12-03 1933-09-07 Bbc Brown Boveri & Cie Improvements in and relating to the tubes of refrigerating plants and the like
SU1386843A1 (ru) * 1986-10-08 1988-04-07 Институт Физико-Технических Проблем Энергетики Ан Литсср Теплообменна винтообразно-закрученна труба
FR2676533A1 (fr) * 1991-05-14 1992-11-20 Valeo Thermique Moteur Sa Echangeur de chaleur a tubes de section ovale, en particulier pour vehicules automobiles.
WO2001018406A1 (fr) * 1999-09-09 2001-03-15 Brown Fintube Tube amélioré pour échangeurs de chaleur
WO2005068062A1 (fr) * 2004-01-20 2005-07-28 Basf Aktiengesellschaft Reacteur a faisceau tubulaire ayant une section transversale helicoidale
DE102007011635A1 (de) * 2006-03-09 2007-09-13 Beijing U Bridge Llc, Chaoyang Wärmetauschrohr mit den spiralförmigen Nuten
US20070246206A1 (en) * 2006-04-25 2007-10-25 Advanced Heat Transfer Llc Heat exchangers based on non-circular tubes with tube-endplate interface for joining tubes of disparate cross-sections
FR2906355A1 (fr) * 2006-09-21 2008-03-28 Valeo Systemes Thermiques Tube pour echangeur de chaleur,echangeur comportant un tel tube et procede de fabrication d'un tel tube

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB398154A (en) * 1930-12-03 1933-09-07 Bbc Brown Boveri & Cie Improvements in and relating to the tubes of refrigerating plants and the like
SU1386843A1 (ru) * 1986-10-08 1988-04-07 Институт Физико-Технических Проблем Энергетики Ан Литсср Теплообменна винтообразно-закрученна труба
FR2676533A1 (fr) * 1991-05-14 1992-11-20 Valeo Thermique Moteur Sa Echangeur de chaleur a tubes de section ovale, en particulier pour vehicules automobiles.
WO2001018406A1 (fr) * 1999-09-09 2001-03-15 Brown Fintube Tube amélioré pour échangeurs de chaleur
WO2005068062A1 (fr) * 2004-01-20 2005-07-28 Basf Aktiengesellschaft Reacteur a faisceau tubulaire ayant une section transversale helicoidale
DE102007011635A1 (de) * 2006-03-09 2007-09-13 Beijing U Bridge Llc, Chaoyang Wärmetauschrohr mit den spiralförmigen Nuten
US20070246206A1 (en) * 2006-04-25 2007-10-25 Advanced Heat Transfer Llc Heat exchangers based on non-circular tubes with tube-endplate interface for joining tubes of disparate cross-sections
FR2906355A1 (fr) * 2006-09-21 2008-03-28 Valeo Systemes Thermiques Tube pour echangeur de chaleur,echangeur comportant un tel tube et procede de fabrication d'un tel tube

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2693152A1 (fr) * 2012-08-03 2014-02-05 Tom Richards, Inc. Échangeur de chaleur ultra-pure en ligne
US9562703B2 (en) 2012-08-03 2017-02-07 Tom Richards, Inc. In-line ultrapure heat exchanger
CN105387747A (zh) * 2015-11-25 2016-03-09 重庆市龙山金属材料有限公司 一种交叉椭圆截面及圆面热交换增强管
CN105387750A (zh) * 2015-11-25 2016-03-09 重庆市龙山金属材料有限公司 一种热交换增强管
CN105387755A (zh) * 2015-11-25 2016-03-09 重庆祥吉机械制造有限公司 一种热交换增强散热器
CN105387508A (zh) * 2015-11-25 2016-03-09 重庆市龙山金属材料有限公司 一种改良热交换增强地暖
CN105387753A (zh) * 2015-11-25 2016-03-09 重庆市龙山金属材料有限公司 一种改良热交换增强散热器
CN105387751A (zh) * 2015-11-25 2016-03-09 重庆祥吉机械制造有限公司 一种新型热交换增强热水器
CN105387760A (zh) * 2015-11-25 2016-03-09 重庆市龙山金属材料有限公司 一种热交换增强空调
CN105387749A (zh) * 2015-11-25 2016-03-09 重庆祥吉机械制造有限公司 一种新型热交换增强地暖
CN105465867A (zh) * 2015-11-25 2016-04-06 重庆市龙山金属材料有限公司 一种热交换增强地暖
CN105387756A (zh) * 2015-11-25 2016-03-09 重庆市龙山金属材料有限公司 一种改良热交换增强空调
CN110553531A (zh) * 2019-10-11 2019-12-10 上海东润换热设备制造有限公司 一种椭圆波节型换热器管束
CN110579122A (zh) * 2019-10-11 2019-12-17 上海东润换热设备制造有限公司 一种换热器

Similar Documents

Publication Publication Date Title
EP2219001A1 (fr) Tube ondulé doté d'une section transversale elliptique
US6786274B2 (en) Heat exchanger fin having canted lances
US4258782A (en) Heat exchanger having liquid turbulator
JP4028591B2 (ja) 伝熱フィンおよびフィンチューブ型熱交換器
WO2016015324A1 (fr) Ailette ondulée aérodynamique pour échangeur thermique à tubes à ailettes
US20160018168A1 (en) Angled Tube Fins to Support Shell Side Flow
EP2236973A2 (fr) Distributeur réfrigérant pour échangeur thermique et échangeur thermique
CN207832006U (zh) 一种换热器翅片
SE1450352A1 (sv) Rörformig motströms luftvärmeväxlare
US20140332188A1 (en) Heat exchanger
CN210198146U (zh) 具有翅片的套管换热器
US20100193172A1 (en) Fin for a heat exchanger
CN107990761A (zh) 一种整圆形孔板支撑轴向凹槽换热管的管壳式换热器
WO2008099434A1 (fr) Echangeur thermique sans tube et son procédé de fabrication
KR20140146236A (ko) 배관용 플렉시블 덕트
CN215810397U (zh) 微通道换热结构
JP2013113525A (ja) 二重管
CN102667288A (zh) 不锈钢制挠性管
WO2019019710A1 (fr) Échangeur de chaleur et dispositif d'échange de chaleur
JP2004191034A (ja) 樹脂材製フィン部材を内装した伝熱管
JP2007147233A (ja) フィンチューブ
CN109900144A (zh) 换热器和具有该换热器的换热装置
CN209926938U (zh) 一种换热装置
JP2007218523A (ja) 熱交換器
JP2005030677A (ja) 樹脂材製フィン部材を外装した伝熱管

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL BA RS

AKY No designation fees paid
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20110219