DE202008010300U1 - Heat exchanger - Google Patents

Abstract

Heat exchanger (1), in particular for a motor vehicle, which has a Block (2) with at least one tubular element (3) and at least one Rib element (4), wherein the at least one tube element (3) each at least a first portion (8) and a second Section (9), wherein the first portion (8) has a larger Has flow cross section as the second section (9), characterized in that in an air flow direction the heat exchanger (1) the first section (8) at an air inlet side and the second section (9) at one Air outlet side is arranged.

Description

The The invention relates to a heat exchanger with the Features according to the preamble of the claim 1.

Of the Efficiency of a heat exchanger results essentially from the ratio of absorbed thermal Energy on the cold side to released energy on the warm Page. A powerful heat exchanger is able to warm up the warming flow of material and strongly cool the other stream.

Around the performance of a heat exchanger To improve, it is possible, for example, its depth to enlarge. At magnification the depth, however, there is a risk that the air side pressure drop increases significantly, the cooling capacity only in small Dimensions increase.

Out DE 1 922 452 is an annular cross-flow heat exchanger with flat-shaped tubes in an annular arrangement on the circumference of a Radialgeblä ses for cooling a flowing through the pipes first medium by a gaseous, promoted by the impeller second medium known. The flat-shaped tubes are arranged fan-like in rows concentric to the impeller in the space which adjoins the impeller in the radial direction, that they are approximately axially to the fan axis and their cross-sectional longitudinal axes approximately parallel to the flow direction of the conveyed by the impeller medium. Their ends open into annular chambers, which are formed in side walls and establish the connection between the individual tube rows. By this configuration, in particular by the laying of the heat exchanger in the region which connects radially directly to the impeller, it is achieved that the heat exchange process takes place in the area of the implementation of the speed energy in pressure energy of the gaseous medium conveyed by the impeller. As a result, the energy conversion takes place by utilizing the so-called Betz effect with particularly favorable efficiency.

adversely in the known from the prior art designs of heat exchangers, however, on the one hand, that elaborate designs are required to powerful To create heat exchangers. On the other hand, the one discussed above increased pressure drop with increasing depth an undesirable Effect.

The Object of the present invention is therefore a To provide heat exchanger, which the air side Reduced pressure drop.

These Task is through a heat exchanger with the Characteristics solved according to claim 1. advantageous Further developments are defined in the subclaims.

According to the Invention is a heat exchanger, in particular for a motor vehicle, provided, which a block having at least one tubular element and at least one rib element, wherein the at least one tubular element in each case at least a first Section and a second section, wherein the first Section a larger flow area as the second section. According to the invention in an air flow direction of the heat exchanger the first section at an air inlet side and the second section arranged on an air outlet side. By the invention Configuration is at large depths of the heat exchanger the air-side pressure drop at a similar high cooling capacity reduced in a simple way.

According to one preferred embodiment, the block has a plurality of tubular elements and rib elements, which in alternating Sequence are arranged.

Preferably the at least one rib member has a first portion and a second section, wherein in the air flow direction of the heat exchanger, the first portion of the rib member at the air inlet side and the second section at the air outlet side is arranged.

According to In another embodiment, the height of the first portion of the rib member smaller than the height the second portion of the rib member.

Especially it is preferred if in the block the rib elements each in their first section and second section corresponding to the pipe distances are adjusted in the transverse direction. That is, the rib elements in particular have a lower height in the area the first section with the larger width of the tubular element, and the Rippenele elements have a larger Height in the area of the second section with the lower Width of the tubular element.

Preferably, the at least one tubular element has a stepped cross-section. There may be one or more stages in the tube member, each stage defining another portion relative to the flow area in the tube member. In this case, the sections can be integrally provided in a one-piece tubular element, which is designed accordingly, or it can for each section of Rohrele ments with a different flow cross-section, a separate pipe element can be used, wherein the individual pipe elements forming the different sections are then arranged one behind the other.

Preferably the at least one tubular element is designed as a flat tube.

About that In addition, the at least one rib element is preferably a world rib educated.

Of the first section of the at least one tubular element has an inner wall on, at which a plurality of the surface of the inner wall magnifying and projecting from this elements, in particular Turbulators, provided, which is a turbulent flow in the first section. Thus, in a simple way and manner in the first section with enlarged Flow diameter a turbulent flow be achieved to the coolant side flow rates evenly distributed in depth.

It is particularly preferred when the turbulators in the inner wall of the first tubular element are embossed. Preferably the projecting elements are formed in the form of so-called winglets, which by means of a stamping process in the inner wall of the be embossed first tubular element.

advantageously, is the second portion of the at least one tubular element as a smooth tube educated. Due to the reduced flow cross section is the additional provision of turbulators or winglets not required in this section.

According to one very particularly preferred embodiment, the at least a tubular element in the first section has a width b1 and the second one Section a width b2, where the ratio of Width b1 to b2 is in a range of 1.2 to 1.7 (1.2 ≦ b1 / b2 ≦ 1.7).

Yet more preferably, this has at least one tube element in the first section a length l1 and the second section has a width l2, where the ratio of width l2 to l1 is in one range from 1.0 to 2.5 (1 ≤ l2 / l1 ≤ 2.5).

at Another preferred embodiment is the first one Section of the ribbed element with a larger one Wall thickness formed as the second portion of the rib member. As a result, the heat exchanger on its front given a greater strength. Especially when the heat exchanger used in commercial vehicles For example, the front can be subject to high loads exposed the use of pressure blasting equipment for cleaning whose pressure is up to 150 bar. By providing of reinforced rib elements or by enlargement the rib thickness in the first section, which is the front side forms under certain circumstances, also improved pressure jet resistance reached.

Farther is according to yet a preferred embodiment the block on a top and a bottom each with a Bottom element provided, which as a connection part to a coolant box the heat exchanger is used.

following An embodiment of the invention is with reference to the attached drawing. Show it:

1 a perspective view of a general structure of a heat exchanger according to the prior art,

2 a cross-section through a section of a heat exchanger according to an embodiment of the invention.

1 shows a perspective view of a general construction of a heat exchanger 1 according to the prior art. The heat exchanger 1 has a block 2 on, which consists of tubular elements 3 in the form of flat tubes and rib elements 4 is constructed in the form of corrugated ribs, which are arranged alternately. The tube ends of the flat tubes open on opposite end faces in each case a collection box, the upper tube ends in an upper water tank 5 and the lower tube ends into a lower plenum box 6 lead. The upper water tank 5 has connecting pieces (not shown) for supply and return of a cooling circuit of a motor vehicle internal combustion engine (not shown). The opposite narrow sides of the block 2 are each with a side panel 7 provided, which is at an upper and lower end portion with a respective bottom element (not shown) in engagement.

2 shows a cross section through a section of a heat exchanger 1 according to an embodiment of the invention. The clipping represents a section of the block 2 in which only three pipe elements 3 with two rib elements interposed therebetween 4 are shown. Each of the pipe elements 3 has a first section 8th and a second section 9 on. The black arrow indicates the general air flow direction of the heat exchanger 1 or the block 2 , The first paragraph 8th is located at the air inlet side of the airflow, and the second section 9 is in the direction of the depth of the heat exchanger 1 behind the first section 8th arranged and forms there at the air outlet end. The first paragraph 8th has a larger flow cross-section than the second section 9 on. Since the tube element is designed as a flat tube, it has a width b1 in the first section and a width b2 in the second section. The width of the first portion and the second portion are selected so that the ratio of the width of the first portion b1 to the width of the second portion b2 is in a range of 1.2 to 1.7 (1.2 ≦ b1 / b2 ≤ 1.7). Furthermore, the first section 8th a length l1 and the second section 9 a length l2. The length of the first section and the second section are chosen so that the ratio of the length of the second section 12 to the length of the first section l1 is in a range of 1 to 2.5 (1 ≦ l2 / l1 ≦ 2.5).

Furthermore, in the first section 8th on an inner wall 10 offensive elements 11 in the form of designed as winglets turbulators, which in the first section 8th having the larger flow area, provide a sufficiently turbulent flow. The second section 9 , which has the smaller flow cross-section, however, is designed as a smooth tube.

Between the pipe elements 8th respectively arranged are the rib elements 4 , which likewise each have a first section 12 and a second section 13 exhibit. The height h1 of the ribs of the rib element 4 in the first section 12 is smaller than the height h2 of the ribs of the rib element 4 in the second section 13 , Essentially, the heights h1 and h2 of the ribs of the first and second sections are the same 12 . 13 of the rib element 4 the different widths b1 and b2 of the first and second sections 8th . 9 of the tubular element 3 out. The length l1 of the first section 8th of the tubular element 3 is substantially equal to the length of the first section 12 of the rib element 4 , In addition, the length is l2 of the second section 9 of the tubular element 3 substantially equal to the length of the second section 13 of the rib element 4 , The rib thickness or the wall thickness of the first section 12 of the rib element 4 is made stronger than the wall thickness of the second section 13 so that the front ribs are arranged when using the heat exchanger 1 in a commercial vehicle can pass a pressure spray test. The first and second sections 8th . 9 of the tubular element 3 lie on a common longitudinal axis. Furthermore, the first and second sections form 8th . 9 a stepped flow area decreasing in the air flow direction from the air inlet side to the air outlet side.

By the configuration of a heat exchanger described above with stepped in the depth pipe elements and with equally graded Rib elements will advantageously be an air side pressure drop reduced at similar high cooling capacity; Farther also thermodynamic advantages are achieved.

1

Heat exchanger

2

block

3

Rohrelment

4

rib element

5

upper cistern

6

lower cistern

7

side panel

8th

first Section of the tubular element

9

second Section of the tubular element

10

inner wall

11

abragendes Element / turbulator

12

first Section of the rib element

13

second Section of the rib element

b1

width the first portion of the tubular element

b2

width the second portion of the tubular element

l1

length the first portion of the tubular element

l2

length the second portion of the tubular element

h1

height the first portion of the rib member

h2

height the second portion of the rib member

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 1922452 [0004]

Claims (15)

Heat exchanger ( 1 ), in particular for a motor vehicle, which has a block ( 2 ) with at least one tubular element ( 3 ) and at least one rib element ( 4 ), wherein the at least one tubular element ( 3 ) each at least a first section ( 8th ) and a second section ( 9 ), the first section ( 8th ) has a larger flow cross-section than the second section ( 9 ), characterized in that in an air flow direction of the heat exchanger ( 1 ) the first paragraph ( 8th ) at an air inlet side and the second section ( 9 ) is arranged on an air outlet side. Heat exchanger ( 1 ) according to claim 1, characterized in that the block ( 2 ) a plurality of tubular elements ( 3 ) and rib elements ( 4 ), which are arranged in an alternating sequence. Heat exchanger ( 1 ) according to claim 2, characterized in that the at least one rib element ( 4 ) a first section ( 12 ) and a second section ( 13 ), wherein in the Luftdurchströ flow direction of the heat exchanger ( 1 ) the first paragraph ( 12 ) of the rib element ( 4 ) at the air inlet side and the second section ( 13 ) is arranged on the Luftaustrisseite. Heat exchanger ( 1 ) according to claim 3, characterized in that the height (h1) of the first section ( 12 ) of the rib element ( 4 ) is smaller than the height (h2) of the second section ( 13 ) of the rib element ( 4 ). Heat exchanger ( 1 ) according to one or more of claims 2 to 4, characterized in that in the block ( 2 ) the rib elements ( 4 ) in each case in their first section ( 12 ) and second section ( 13 ) are adapted according to the pipe distances in the transverse direction. Heat exchanger ( 1 ) according to one or more of claims 1 to 5, characterized in that the at least one pipe element ( 3 ) has a stepped cross-section. Heat exchanger ( 1 ) according to one or more of claims 1 to 6, characterized in that the at least one tubular element ( 3 ) is designed as a flat tube. Heat exchanger ( 1 ) according to one or more of claims 1 to 7, characterized in that the at least one rib element ( 4 ) is designed as a corrugated fin. Heat exchanger ( 1 ) according to one or more of claims 1 to 8, characterized in that the first section ( 8th ) of the at least one tubular element ( 3 ) an inner wall ( 10 ), at which a plurality of the surface of the inner wall ( 10 ) enlarging and projecting elements ( 11 ), in particular turbulators, is provided which a turbulent flow in the first section ( 8th ). Heat exchanger ( 1 ) according to claim 9, characterized in that the turbulators in the inner wall ( 10 ) of the first tubular element ( 3 ) are imprinted. Heat exchanger ( 1 ) according to one or more of claims 1 to 10, characterized in that the second section ( 9 ) of the at least one tubular element ( 3 ) is designed as a smooth tube. Heat exchanger ( 1 ) according to one or more of claims 1 to 11, characterized in that the at least one pipe element ( 3 ) in the first section ( 8th ) a width b1 and the second section ( 9 ) has a width b2, wherein the ratio of the width b1 to b2 is in a range of 1.2 to 1.7. Heat exchanger ( 1 ) according to one or more of claims 1 to 12, characterized in that the at least one pipe element ( 3 ) in the first section ( 8th ) a length l1 and the second section ( 9 ) has a width l2, wherein the ratio of the width l2 to l1 is in a range of 1.0 to 2.5. Heat exchanger ( 1 ) according to one or more of claims 1 to 13, characterized in that the first section ( 12 ) of the rib element ( 4 ) is formed with a larger wall thickness than the second section ( 13 ) of the rib element ( 4 ). Heat exchanger ( 1 ) according to one or more of claims 1 to 14, characterized in that the block ( 2 ) is provided on an upper side and a lower side in each case with a bottom element which serves as a connection part to a coolant box of the heat exchanger ( 1 ) serves.