EP1308685B1 - Heat exchanger - Google Patents

Description

The invention relates to a heat exchanger, in particular in cross-flow design, which can be flowed through by at least two separate media.

Heat exchangers of the generic type are for example from the DE 199 09 881 A1 known. This known heat exchanger has stacked plates which are partially spaced from each other and are partially in contact. In this way, in each case a flow path for a medium, for example a fluid, is formed between respectively adjacent plates in a heat transfer area. So that the plates can be arranged spaced from each other, are formed on these knobs and beads.

The plates further include inlet passage apertures and exit passage apertures adjacent the heat transfer areas. By layered, sandwich-like arrangement of the plates, the heat exchanger is formed. The plates are in this case rotated 90 ° to each other - with respect to a central axis of the plates - arranged so that it comes to sealed flow channels. In order to achieve a sealing of the flow channels, the plates are soldered to the adjacent knobs and / or beads. It is disadvantageous that a considerable production cost is given. Furthermore, even minor Height tolerances in the beads and / or knobs to a gap, which can be compensated by soldering only with a considerable additional effort or in extreme cases.

From the EP 0 623 798 B1 a plate heat exchanger is known in which trough-shaped heat exchanger plates are stacked in one another. Between the heat exchanger plates turbulence inserts can be arranged to form flow channels. The heat exchanger plates with each other are soldered together in their peripheral edge regions. To form the mutually sealed flow paths, the arrangement of additional sealing washers is provided. This results in addition to an increased cost of materials a high production cost.

Further plate heat exchangers are from the DE 195 17 174 C1 , of the JP 83 27 275 A or the US 6,182,748 B1 known.

The invention has for its object to provide a heat exchanger of the generic type, which is characterized by a simple construction and associated simple production possibility

According to the invention this object is achieved by a heat exchanger with the features mentioned in claim 1 characterized in that over the circumference of the plates successive areas, each having breakthroughs are formed alternately from the plane of the plates opposite, can be in a simple manner by stacking such Form plates heat exchanger with adjacent, mutually sealed flow paths. The regions of adjacent plates which are alternately formed from the plane of the plates come into contact with each other when the plates are stacked and thus, on the one hand, determine the formation of the flow paths between the plates and, on the other hand, simultaneously serve to seal adjacent flow paths. Due to a particularly relatively large-area design of the alternately shaped regions, a large support surface between the adjacent plates is obtained at the same time, so that a heat exchanger having these plates has a high stability. At the same time thereby the dense joining of the adjacent plates is simplified. In particular, manufacturing tolerances and / or assembly tolerances can thus not lead to a gap formation between adjacent plates.

According to the invention it is provided that the plates are cup-shaped with a base extending from a bottom. The edge is preferably conical to the ground. This advantageously makes it possible to arrange the plates to complete the heat exchanger self-aligning one above the other. Furthermore, this results in a minimum gap geometry between adjacent plates, so that they can be joined in a particularly pressure-tight manner in a particularly simple and secure manner.

According to the invention, it is provided that the regions having the apertures pass over steps into the heat transfer region. The steps are substantially perpendicular to the heat transfer area. Such heat exchanger resulting plates can be particularly easily manufactured in one piece by the simple geometry. In addition, the height of the steps makes it possible to determine the desired spacing between the adjacent plates relative to each other.

In addition, it is provided in a preferred embodiment of the invention that diametrically opposite openings of the plates are the same size, wherein preferably an upper breakthrough to twice the material thickness is formed larger than a lower breakthrough in superimposed plates. Preferably, it is further provided that the openings are each surrounded by a peripheral bead. This makes it very advantageous to add the plates to form sealed against each other flow paths pressure-tight. Due to the peripheral beads a minimum gap geometry between adjacent plates is obtained, which can be closed pressure-tight in a simple manner.

Further preferred embodiments of the invention will become apparent from the remaining, mentioned in the dependent claims characteristics.

Figur 1

eine Draufsicht auf eine Platte eines Wärmeübertragers;

Figur 2

eine Schnittdarstellung durch eine Anordnung von vier übereinander gestapelten Platten gemäß Linie A-A aus Figur 1;

Figur 3

eine Schnittdarstellung durch vier übereinander gestapelte Platten gemäß Schnittlinie B-B gemäß Figur 1;

Figur 4

eine Detailvergrößerung;

Figur 5a

Perspektivansichten gestapelter Platten

und 5b und Figur 6a und 6b

Perspektivansichten in Explosionsdarstellung eines Wärmetauschers.

The invention will be explained in more detail in an embodiment with reference to the accompanying drawings. Show it:

FIG. 1

a plan view of a plate of a heat exchanger;

FIG. 2

a sectional view through an arrangement of four stacked plates according to line AA FIG. 1 ;

FIG. 3

a sectional view through four stacked plates according to section line BB according to FIG. 1 ;

FIG. 4

an enlarged detail;

FIG. 5a

Perspective views of stacked plates

and Figure 5b and Figures 6a and 6b

Perspective views in exploded view of a heat exchanger.

FIG. 1 shows a plan view of a total designated 10 heat exchanger. FIG. 2 shows a longitudinal section along the line AA through the heat exchanger 10, while FIG. 3 a longitudinal section along the line BB through the heat exchanger 10 shows. In the representations in the FIGS. 1, 2 and 3 are the later still to be explained cover plate and connection plate not drawn.

The heat exchanger 10 consists of plates 12 stacked on one another. According to the exemplary embodiment shown, four plates 12 are provided, it being understood that the number of plates 12 can be smaller or larger in accordance with the requirements for the heat exchanger 10.

The structure of the plates 12 is based on the plan view in FIG. 1 explained on the upper plate 12 of the heat exchanger 10. The plate 12 is substantially disc-shaped and has a bottom 14 which is encompassed by a bevelled edge 16. This results in a, in the sectional views clearly becoming, cup-shaped shape of the plates 12. The base 14 forms a heat transfer region 18, the of Areas 20, 22, 24 and 26 is encompassed. The regions 20, 22, 24 and 26 are arranged in the clockwise direction around the heat transfer region 18 and thus adjoin the heat transfer region 18 and outer edges 30 on the edge 16 on the one hand via inner edges 28. To better illustrate the structure of the plates still to be explained here are the areas associated with the areas 20 and 24 with 28 and outer edges with 30 and the areas 22 and 26 associated inner edges with 28 'and the outer edges with 30'.

The heat transfer area 18 coincides with the plane of the bottom 14 of the plate 12. According to the graphic representation in FIG. 1 It is assumed that the heat transfer area 18 is in the paper plane. The opposing areas 20 and 24 are formed so that they are below the plane of the heat transfer area 18, while the opposing areas 22 and 26 are formed such that they are above the plane of the heat transfer area 18. The inner edges 28, 28 'thus form a step, as it were, over which the regions 20, 22, 24, 26 merge into the heat transfer region 18. As the sectional views make clear, the inner edges 28, 28 'in this case are not formed substantially perpendicular to the plane of the heat transfer region 18. The area 24 has an opening 34, while the area 20 has an opening 32. Analogously, the region 26 has an opening 36 and the region 22 has an opening 38. The openings 32, 34, 36 and 38 have a substantially oval shape, which is flattened on the side facing the heat transfer area 18. The apertures 32 and 34 are the same size and the apertures 36 and 38 are also the same size. The openings 32 and 34 are in this case larger than the openings 36 and 38 and that formed according to a double thickness of the plate 12. This point of view is based on FIG. 4 discussed in more detail.

The openings 32, 34, 36, 38 are each surrounded by a peripheral bead 40, which - as shown in FIG FIG. 1 - Collar upwards.

Structure, function and installation of the heat exchanger 10 are based on the detail magnification in FIG. 4 be explained in more detail.

In FIG. 4 are shown in sections four stacked plates 12. It is clear that the plates 12 engage each other with their edges 16. The edges 16 are conical, so that a self-aligned stacking of the plates 12 is possible. When stacking the plates 12 every other plate - compared to the representation in FIG. 1 - arranged rotated by 90 °. As a result, the heat exchanger 10 can be made of identical plates 12. Due to the 90 ° rotated arrangement to an imaginary center axis 42 ( FIG. 1 ) of the plates 12 it is achieved that a region 24 of the uppermost plate 12 comes to rest on a region 22 of the plate 12 arranged underneath. Similarly, the area 26 of the uppermost plate 12 comes to lie on an area 24 (not shown) of the plate 12 below. Over the circumference of the plates 12, this arrangement results analogously.

Since the regions 20, 22, 24, 26 are formed oppositely to the plane of the plates 12 in opposite directions, this results in that in superimposed regions 20, 22, 24 and 26, the heat transfer regions 18 of two adjacent plates 12 are spaced from each other and each have a flow path 44 or 46 train. The flow paths 44 and 46 are sealed against each other, while the flow paths 44 with each other or the flow paths 46 with each other via the apertures 32, 34, 36 and 38 - depending on the arrangement the plates 12 - communicate with each other. As a result, the flow paths 44 and 46 with separate media, such as fluids, acted upon. In the embodiment shown, the flow paths 44 and 46 are arranged such that media flowing through them intersect, resulting in the formation of a cross-flow heat exchanger. Within the flow paths 44 and 46 are here indicated turbulence elements 48, for example, turbulence plates, arranged, which lead to a swirling of the medium flowing through and thus a good heat transfer via the heat transfer areas 18. The arrangement and function of the turbulence elements 48 and the heat transfer between the flow paths 44 and 46 are well known, so that it should not be discussed further in the context of the present description.

Based on the illustration in FIG. 4 It is clear that when stacking the plates 12, the peripheral beads 40 of the apertures 32, 34, 36 and 38 engage in accordance with the arrangement of the plates 12 in one another. This is possible because the openings 32 and 34 are formed by the double thickness of the plates 12 larger than the openings 36 and 38th

As a result, the beads 40 of the lower plates 12 engage positively in the beads 40 of the upper plates 12. Similarly, the edge 16 of the upper plates 12 also engages in the edge 16 of the lower plates 12 in a form-fitting manner. Thus, only a joining of the superimposed plates 12 in the region of the edges 16 or in the region of the beads 40 is necessary for producing a pressure-tight arrangement. This can be done by methods known per se, such as gluing, soldering, laser welding or other suitable methods. These are selected in particular on the basis of the material properties of the plates 12. As a result of this joining of the plates 12, the turbulence elements 48 inserted between the heat transfer areas 18 are fixed at the same time, without these having to be additionally joined to the plates 12. For adjustment during assembly it can be provided that the plates 12 in the region of the heat transfer planes 18 at least one, preferably two nubs 50 (FIG. FIGS. 5a and 5b ), in which form-fitting the profiling of the turbulence elements 48 engage.

In FIG. 4 Furthermore, the flow direction of a medium 52 is indicated. This will - about the in FIG. 4 not shown connection plate - the heat exchanger 10 is supplied. According to the arrangement of the plates 12, this results in two separate flow paths, the each have one entry and one exit each. In FIG. 4 the entrance 54 of a flow path is shown. This is formed by the superimposed openings 34 and 38 of the plates 12. The medium 52 flowing into the inlet 54 thus enters the flow path or the flow paths 46. The second medium is - FIG. 4 not shown - guided by the flow paths 44 in an analogous manner. The leadership of the media through the heat exchanger 10 is the person skilled in the art, so that will not be discussed in detail.

Based on FIG. 4 Thus, it becomes clear that in order to obtain flow paths 44 and 46 which are guided in a pressure-tight manner, only the identically constructed plates 12 are stacked one above the other by 90 ° and joined at the edges 16 and peripheral beads 40. The at least partial meshing of the edges 16 or the peripheral beads 40 of the discs 12 results in minimal gaps between the plates 12, so that even with manufacturing tolerances of the heat exchanger 10, for example by fluctuating heights of the turbulence inserts 48, a minimum gap geometry is guaranteed. This can be closed in a simple manner by means of known joining methods.

In the FIGS. 5a and 5b schematically again the four stacked discs 12 are shown. On the basis of this perspective view it is clear that by means of the stacking of the disks 12, a very compact design of the heat exchanger 10 can be achieved.

In the Figures 6a and 6b is shown in each case in a schematic exploded view of the heat exchanger 10. In addition to the plates 12, a cover plate 56 and a connection plate 58 are shown here. Cover plate 56 and connection plate 58 have at their respective sides facing the plates 12 a corresponding to the plates 12 structure, that is, there are the regions 20, 22, 24 and 26 in the plane corresponding offset to a heat exchanger region 18 is formed. This allows in the region of the cover plate 56, a tight closure of the openings 30, 32, 34, 36 and in the region of the connection plate 58, the supply of the media, between which the heat exchange should take place.

The cover plate 56 is formed closed to the outside, while the connection plate 58 has the inlets or outlets for the flow paths. Here, the inlet 54 and an outlet 60 for the medium 52 and an inlet 62 and an outlet 64 for a medium 66 is shown.

The discs 12 and 56 and 58 and the turbulence inserts 48 may be made of metal, for example aluminum, copper, stainless steel and / or plastic. The choice of material depends in particular on a resistance to the media 52 or 66 guided between the heat exchanger 10. A wall thickness of the plates 12 is, for example, between 0.1 and 1 mm. A height of the turbulence inserts 48 may be, for example, between 1 and 10 mm.

The representation in the FIGS. 1 to 6 is just an example. Thus, instead of a circular design, an oval or angular, for example, square design of the plates 12, 56 and 58 may be provided. Furthermore, by appropriate design of voregesehen over the circumference of the plates, the openings having regions a heat exchanger with more than two entries 54 and 62 and more than two outlets 60 are formed 64 relationship 64.

The heat exchanger 10 can be used, for example, as a condenser to condense water out of moist air with its help, without this discharging ions from a capacitor material. Another possible use of the heat exchanger 10 is in a gas generating system of a fuel cell operated Kratftfahrzueges, the heat exchanger 10 is designed for this purpose as a chemical reactor in which each second fluid path is provided as a reaction channel with a catalyst coating and the remaining fluid paths for cooling or heating of the reaction channels. Likewise, use as a catalytic reactor is possible. Furthermore, a use as oil cooler or fuel cooler is possible.

Claims (8)

1. A heat exchanger, in particular of countercurrent design, through which at least two separate media can flow, comprising plates stacked on one another, which are spaced apart from one another in some regions and which are in contact with one another in some regions so that flow paths are formed between adjacent plates in a heat exchange region, wherein the plates comprises apertures adjacent to the heat exchange region, and the plates are spaced from one another by shaped-out portions thereof, wherein regions (20, 22, 24, 26) arranged in succession over the periphery of the plates (12) and which have apertures (32, 34, 36, 38) are shaped-out alternately in opposite directions from the plane of the plates (12), the plates (12) are formed in a pot-shaped manner with an edge (16) extending from a base (14) and the base (14) forms the heat exchange region (18), wherein the regions (20, 22, 24, 26) transition via steps (28, 28') into the heat exchange region (18) and the steps (28, 28') extend substantially perpendicular to the heat exchange region (18), wherein the steps (28, 28') and therefore the regions (20, 24 and 22, 26) originate in opposite directions from the heat exchange region (18), wherein the apertures (32, 34) are larger than the apertures (36, 38) by an amount corresponding to double the material thickness of the plate (12) and the apertures (32, 34, 36, 38) are substantially oval in shape.
2. The heat exchanger according to claim 1, characterised in that the apertures (32, 34 and 36, 38) arranged diametrically opposed in relation to a central axis (42) of the plates (12) are of equal size.
3. The heat exchanger according to one of the preceding claims, characterised in that the apertures (32, 34, 36, 38) are each surrounded by a peripheral bead (40).
4. The heat exchanger according to one of the preceding claims, characterised in that the edges (16) of the plates (12) extend conically to the base (14).
5. The heat exchanger according to one of the preceding claims, characterised in that turbulence elements (48) are arranged between adjacent plates (12).
6. The heat exchanger according to claim 5, characterised in that the plates (12) have at least one knob (50) in their heat exchange region (18) to position the turbulence elements (48) with a positive fit.
7. The heat exchanger according to one of the preceding claims, characterised in that the heat exchanger (10) comprises a cover plate (56) and a connector plate (58), between which the stacked plates (12) are arranged.
8. The heat exchanger according to claim 7, characterised in that the cover plate (56) and the connector plate (58) have a structure corresponding to the plates (12), and in particular on one side have regions (20, 22, 24, 26) which are likewise offset vertically in relation to one another.

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