EP1398592B1 - Echangeur de chaleur à tubes plats - Google Patents

Echangeur de chaleur à tubes plats Download PDF

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Publication number
EP1398592B1
EP1398592B1 EP03020179.2A EP03020179A EP1398592B1 EP 1398592 B1 EP1398592 B1 EP 1398592B1 EP 03020179 A EP03020179 A EP 03020179A EP 1398592 B1 EP1398592 B1 EP 1398592B1
Authority
EP
European Patent Office
Prior art keywords
heat exchanger
exchanger according
rib
medium
fin
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.)
Expired - Lifetime
Application number
EP03020179.2A
Other languages
German (de)
English (en)
Other versions
EP1398592A1 (fr
Inventor
Rainer Dr.-Ing Richter
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.)
Mahle Behr GmbH and Co KG
Original Assignee
Mahle Behr GmbH and Co KG
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 Mahle Behr GmbH and Co KG filed Critical Mahle Behr GmbH and Co KG
Publication of EP1398592A1 publication Critical patent/EP1398592A1/fr
Application granted granted Critical
Publication of EP1398592B1 publication Critical patent/EP1398592B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime 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
    • F28F1/00—Tubular elements; Assemblies of tubular elements
    • F28F1/10—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
    • F28F1/12—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element
    • F28F1/126—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only outside the tubular element consisting of zig-zag shaped fins
    • F28F1/128—Fins with openings, e.g. louvered fins

Definitions

  • the invention relates to a heat exchanger with pipes and ribs according to the preamble of claim 1.
  • JP 8-271169 discloses such a heat exchanger.
  • heat exchangers are on the one hand so-called mechanically joined heat exchangers, d. H. with round tubes and flat ribs, which are penetrated by the round tubes and with these over ribbed passages in heat-conducting and mechanical connection.
  • soldered heat exchangers consist of a heat exchanger network with flat tubes and arranged between them corrugated fins, which are soldered to the flat tubes at their wave crests.
  • a liquid medium (coolant) flows through the round tubes or flat tubes, and a gaseous medium (air) flows through the flat ribs or corrugated ribs, ie. H.
  • a liquid medium coolant
  • a gaseous medium air
  • the corrugated fins are approximately zigzag-shaped, ie they form with the walls of the flat tubes approximately triangular flow channels, in which therefore two rib surfaces are arranged inclined to each other (V-type).
  • the newly formed rib surfaces are occupied by so-called gills, ie with slots through which the air is deflected from one flow channel into the adjacent one.
  • This rib configuration serves on the one hand to increase the heat transfer surface on the air side and on the other hand improving the heat transfer by increasing the turbulence.
  • boundary layers are formed, which are broken up again by the gills.
  • a modified ribbed form the so-called parallel rib or U-type, was replaced by the US-A 5,271,478 known, and also for a soldered flat tube heat exchanger.
  • the ribbed surfaces are arranged parallel to one another here, ie the ribbed surfaces and the tube walls form approximately rectangular flow channels for the air.
  • the rib areas are occupied by gills, with the gill angle offering a further possibility for influencing the boundary layers and the turbulence.
  • a problem with the known abovementioned rib configurations is that the gills can not be cut over the full width of the ribbed surfaces, because the ribbed surfaces in the area close to the wall pass into a radius. In the area of this rib bending radius, therefore, no turbulence-increasing means are present, which in this area results in a relatively thick boundary layer, ie. H. laminar flow with poor heat transfer leads. Partly occur in the immediate pipe wall area, the highest flow velocities of the air, whereby the heating of the air and thus the heat dissipation in these areas is the worst. Even with mechanically joined heat exchangers similar problems exist in the near-wall region of the round tubes between the flat ribs.
  • the solution to this problem arises from the features of claim 1.
  • the invention is based on the recognition that the air flow or the heat transfer in the areas of the pipe rib contact point can still be improved - therefore according to the invention there are additional interference elements provided in a different geometric configuration, which act essentially as a vortex generator and thus have a turbulence of the flow result.
  • the boundary layers are also broken or disturbed in the region of the rib close to the tube wall.
  • the interference elements according to the invention can in principle be provided in the above-mentioned rib shapes, ie in flat ribs and corrugated ribs, the latter with inclined and parallel rib surfaces, however, there is an advantage for the parallel rib, because there is a symmetrical flow in the flow channel and in the "wave trough" , That is, the bent portion of the rib more space for the arrangement of the interfering elements is present.
  • the curved rib portion has a flat central portion.
  • the rib base is slightly widened and created the necessary space for the arrangement of the interfering elements.
  • interfering elements themselves can have a wide variety of embodiments, with an expression of the ribbed sheet in the form of a round or elongated nub or in the form of a truncated cone or a conical tip are advantageous embodiments that can be relatively easily stamped in the conventional production of the rib.
  • a further advantageous embodiment of the ribbed sheet partially cut or punched out and bent-surface elements, eg. B. in the form of a ramp which forms a trailing edge for the air flow and thus causes turbulence.
  • flaps can be bent out of the ribbed plate and placed parallel or obliquely in the air flow become. The angle of attack of the lobes or flags also results in a turbulence.
  • the interference elements develop their maximum effect when they are within predetermined dimensions, which also result from the dependent claims.
  • the upper limit for the height of the interfering elements results from the fact that they do not protrude into the region of the gill flow and also must not significantly increase the pressure drop of the air flow.
  • similar interference elements can be arranged in or on the pipe wall between two wave crests, z. B. by impressing the pipe wall inwards, d. H. to the liquid side.
  • An expression of the pipe wall to the air side is possible, for.
  • winglets d. H. V-shaped forms.
  • Fig. 1 shows a corrugated fin 1 only partially shown in cross section, arranged between two flat tubes 2, 3, which are only partially shown as pipe wall pieces.
  • the corrugated fin 1 and the flat tubes 2, 3 are parts of a heat exchanger network, not shown, which is part of a heat exchanger in a known type.
  • heat exchangers can be, for example, coolant radiators for cooling an internal combustion engine of a motor vehicle or else refrigerant condensers as part of an automotive air conditioning system.
  • Both heat exchangers have in common that a liquid and / or vapor medium flows through the tubes, while the outside of the tubes, whose surface is enlarged by the corrugated fins, is exposed to ambient air. The air is thereby promoted by back pressure or by a blower.
  • the corrugated fin 1 has two mutually inclined, ie an acute angle with each other forming rib surfaces 4, 5, which are connected to each other via a bend piece 6, the so-called wave crest.
  • the wave crest 6 is soldered to the pipe wall 2.
  • the rib surfaces 4, 5 have so-called gills 7, 8, which in each case extend to the beginning of the elbow 6, ie, to a distance a to the pipe wall 2, 3.
  • the rib surfaces 4, 5 form with the pipe wall 3 is an approximately triangular flow channel 9.
  • the mean distance of the rib surfaces 4, 5 is measured in a median plane m and is denoted by t.
  • the corrugated fin 1 extends to the right and left in analog training and with the same pitch t.
  • a recess 11 is formed in dashed lines in the pipe wall 3, which is to act as a disturbance element or vortex generator for the air flow in this near-wall area.
  • a disruptive element which in principle also in the opposite direction, d. H. can be formed into the flow channel 9, is intended as an additional option to the rib-side interfering element 10.
  • this simultaneously acts as a disruptive element on the inside of the tube wall for the coolant or refrigerant flowing there.
  • Fig. 2 shows a different rib shape, namely a so-called parallel rib 12 with parallel to each other or U-shaped rib surfaces 13, 14 which are interconnected via a bend piece 15.
  • the two rib surfaces 14, 15 also have known gills 16, 17, which have a length l and thus do not extend over the entire channel cross-section, but in each case have a distance a from the pipe walls 18.
  • the elbow 15 is composed of three sections, namely two outer approximately circularly curved portions 15a, 15b and a middle relatively flat portion 15c together.
  • the rib surfaces 13, 14 in conjunction with the elbow 15 and the tube wall 19 thus form an approximately rectangular flow channel 20 with a constant rib spacing or a rib pitch t.
  • a knob-shaped interference element 21 is arranged, which is formed from the rib material in the direction of the flow channel 20.
  • the contour of this knob-shaped interference element 21 shows a view in the direction A: the shape 21 has an approximately oval contour with a longitudinal extent K and a width B.
  • These interference elements 21 are - as also apparent from the following representations - aligned in the air flow direction one behind the other, so that in these areas the boundary layer is disturbed and a turbulence is generated.
  • a turbulent flow is generated.
  • Fig. 3 shows a parallel rib 22 of the same configuration as the parallel rib 12 in FIG Fig. 2 with the difference that instead of the knob-like expression 21 here a metal strip in the form of a flag 23 is provided as a disruptive element.
  • This flag 23 extends with a height H, which corresponds approximately to the distance a, in the air flow channel, ie until the beginning of the gills.
  • Fig. 4 shows a longitudinal section through a rib or air flow channel with a view of a rib surface 30 with gills 31.
  • the rib 30 is soldered with its upper corrugation 30 a with a tube wall 32 of a not fully illustrated flat tube, and a lower crest 30 b is connected to a tube wall 33 a soldered to adjacent flat tube.
  • interference elements 34 are arranged, which have approximately the shape of a conical tip and are embossed from the material of the rib 30.
  • the air flow is thus disturbed in the lower region 30b of the rib 30 by the interference elements 34, which are arranged one behind the other and project with their tips into the air flow. There are formed behind each interfering element 34 vortex, which improve the heat transfer in this area.
  • the interference elements 34 thus act as a vortex generator.
  • a partial section in the plane IV-IV shows the profile of the gills 31, which - in the direction of employment - have a Kiementiefe T.
  • Fig. 5 shows the same representation as in Fig. 4 However, with another embodiment of interference elements 35 which are round or oval and also embossed from the fin material.
  • Fig. 6 shows a similar representation as 4 and 5
  • the interference elements 36 are formed as a ramp 37, which are cut out of a rib 38 and bent into the air flow L.
  • the ramp 37 is characterized by a height H and a length K.
  • the rib 38 is soldered in this area with a tube wall 39.
  • the ramp 37 has a tear-off edge 40, at which air turbulence form.
  • Fig. 7 shows a further embodiment of interference elements 41, the flap-shaped and as a detail Y in Fig. 9 are shown.
  • the interference element 41 is formed as a rectangular flap 42, which is cut out of a ribbed bottom 43 and bent into the air flow L.
  • the tab 42 which has a height H and a length K, is in this embodiment with its surfaces parallel to the air flow L and thus acts with its leading edge 43 as a "boundary layer breaker".
  • Fig. 10 shows an enlarged sectional view of the knob-shaped expression 21 in Fig. 2 ,
  • the rib 15 is soldered via Lötmenisken 45 with the tube wall 18.
  • the central region 15c has a knob-like expression 21, which protrudes with a height H in the air flow channel.
  • the production of this expression 21 is possible without great effort when rolling the ribs by appropriate embossing nubs are provided on the rollers.

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  • 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)

Claims (16)

  1. Echangeur de chaleur comprenant des tubes plats et des ailettes ondulées, où les tubes plats peuvent être traversés par un premier milieu, et les ailettes ondulées peuvent être contournées par un second milieu et présentent des surfaces d'ailettes comportant des ouïes, où les tubes plats sont au contact de crêtes ondulées des ailettes ondulées où, dans la zone d'un point de contact entre les tubes et les ailettes, il est prévu au moins un élément perturbateur pour l'écoulement du second milieu, caractérisé en ce qu'au moins un élément perturbateur présente une hauteur H perpendiculaire à une direction d'écoulement principal du second milieu, et les ouïes présentent un intervalle a par rapport au point de contact entre les tubes et les ailettes, où s'applique la relation suivante : 0,1 a ≤ H ≤ 1,0 a.
  2. Echangeur de chaleur selon la revendication 1, caractérisé en ce que les tubes plats et les ailettes ondulées sont assemblés les uns aux autres par brasage.
  3. Echangeur de chaleur selon l'une ou l'autre des revendications précédentes, caractérisé en ce que les ailettes ondulées présentent des surfaces d'ailettes inclinées les unes par rapport aux autres.
  4. Echangeur de chaleur selon l'une quelconque des revendications précédentes, caractérisé en ce que les ailettes ondulées présentent des surfaces d'ailettes parallèles entre elles.
  5. Echangeur de chaleur selon la revendication 4, caractérisé en ce que les crêtes ondulées présentent à chaque fois trois parties, à savoir deux parties extérieures ayant une courbure relativement importante et une partie centrale ayant une courbure plus petite ou bien sans courbure.
  6. Echangeur de chaleur selon l'une quelconque des revendications précédentes, caractérisé en ce que, dans la zone d'une crête ondulée, il est prévu plusieurs éléments perturbateurs pour l'écoulement du second milieu.
  7. Echangeur de chaleur selon la revendication 6, caractérisé en ce que plusieurs éléments perturbateurs d'une crête ondulée sont disposés en étant alignés dans la direction d'écoulement principal du second milieu.
  8. Echangeur de chaleur selon l'une quelconque des revendications précédentes, caractérisé en ce qu'au moins un élément perturbateur est configuré, à partir du matériau des ailettes, comme une partie saillante en forme de téton.
  9. Echangeur de chaleur selon l'une quelconque des revendications précédentes, caractérisé en ce qu'au moins un élément perturbateur est configuré comme une patte, où la patte est estampée en particulier à partir du matériau des ailettes.
  10. Echangeur de chaleur selon la revendication 9, caractérisé en ce que la patte est placée de façon inclinée par rapport à une direction d'écoulement principal du second milieu.
  11. Echangeur de chaleur selon la revendication 9 ou 10, caractérisé en ce que la patte est configurée comme une rampe.
  12. Echangeur de chaleur selon la revendication 9 ou 10, caractérisé en ce que la patte est configurée comme une languette.
  13. Echangeur de chaleur selon l'une quelconque des revendications précédentes, caractérisé en ce qu'au moins un élément perturbateur présente une longueur K et les ouïes présentent une profondeur T où s'applique la relation suivante : 0,5 T ≤ K ≤ 2,0 T.
  14. Echangeur de chaleur selon l'une quelconque des revendications précédentes, caractérisé en ce qu'au moins un élément perturbateur présente une largeur B, et le point de contact associé, entre les ailettes et les tubes, présente un intervalle t par rapport à un point de contact voisin, entre les ailettes et les tubes, où s'applique la relation suivante : 0,1 t ≤ B ≤ 0,5 t.
  15. Echangeur de chaleur selon l'une quelconque des revendications précédentes, caractérisé en ce qu'un tube plat présente, entre deux crêtes ondulées d'une ailette ondulée, au moins un deuxième élément perturbateur pour l'écoulement du second milieu.
  16. Echangeur de chaleur selon la revendication 15, caractérisé en ce qu'au moins un deuxième élément perturbateur est configuré comme une partie en saillie par rapport à une paroi tubulaire.
EP03020179.2A 2002-09-10 2003-09-05 Echangeur de chaleur à tubes plats Expired - Lifetime EP1398592B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10242188 2002-09-10
DE2002142188 DE10242188A1 (de) 2002-09-10 2002-09-10 Flachrohr-Wärmeübertrager

Publications (2)

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EP1398592A1 EP1398592A1 (fr) 2004-03-17
EP1398592B1 true EP1398592B1 (fr) 2015-07-22

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EP03020179.2A Expired - Lifetime EP1398592B1 (fr) 2002-09-10 2003-09-05 Echangeur de chaleur à tubes plats

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DE (1) DE10242188A1 (fr)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006000634A1 (de) * 2006-01-03 2007-07-05 Modine Manufacturing Co., Racine Wellrippen für Wärmetauscher
DE102008007608A1 (de) 2008-02-04 2009-08-06 Behr Gmbh & Co. Kg Wärmeübertrager mit Rohren
DE102008045845A1 (de) 2008-09-05 2010-03-11 Behr Gmbh & Co. Kg Strömungsleitelement und Wärmetauscher
DE102016213197A1 (de) 2016-07-19 2018-01-25 Mahle International Gmbh Wellrippe eines Wärmeübertragers und Wärmeübertrager
DE102019218266A1 (de) * 2019-11-26 2021-05-27 Mahle International Gmbh Wellrippenstruktur
DE102020100105A1 (de) 2020-01-06 2021-07-08 Volkswagen Aktiengesellschaft Wärmeübertrager

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3250325A (en) * 1963-02-19 1966-05-10 Ford Motor Co Heat exchange device
US4311193A (en) * 1980-07-14 1982-01-19 Modine Manufacturing Company Serpentine fin heat exchanger
JP2949963B2 (ja) * 1991-10-18 1999-09-20 株式会社デンソー コルゲートルーバフィン型熱交換器
JP3622297B2 (ja) * 1995-02-03 2005-02-23 株式会社デンソー 熱交換器
AU4359000A (en) * 1999-04-19 2000-11-02 Peerless Of America, Inc. An improved fin array for heat transfer assemblies and method of making same
US6598669B2 (en) * 1999-04-19 2003-07-29 Peerless Of America Fin array for heat transfer assemblies and method of making same

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Publication number Publication date
EP1398592A1 (fr) 2004-03-17
DE10242188A1 (de) 2004-03-18

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