EP3191783A1

EP3191783A1 - Stacked-plate heat exchanger

Info

Publication number: EP3191783A1
Application number: EP15759671.9A
Authority: EP
Inventors: Marco Renz; Volker Velte; Boris Kerler
Original assignee: Mahle International GmbH
Current assignee: Mahle International GmbH
Priority date: 2014-09-08
Filing date: 2015-08-18
Publication date: 2017-07-19
Also published as: WO2016037810A1; KR20170055980A; DE102014217920A1; JP2017528678A; US20170254597A1

Abstract

The invention relates to a stacked-plate heat exchanger (1), in particular an intercooler, comprising a high-temperature coolant circuit (HT) and a low-temperature coolant circuit (NT) and comprising heat-exchanger plates (2) stacked one on the other, through which two coolants (3, 4) having a different temperature level in the high-temperature coolant circuit (HT) and in the low-temperature coolant circuit (NT) flow on one side and a medium (5) to be cooled, in particular charge air, flows on the other side. It is essential to the invention that the heat-exchanger plates (2) have an embossed partition (6) for separating the high-temperature coolant circuit (HT) and the low-temperature coolant circuit (NT).

Description

Stacked-plate heat exchanger

The present invention relates to a stacked plate heat exchanger, in particular a charge air cooler, with a high-temperature coolant circuit and a low-temperature coolant circuit.

In modern motor vehicles, a steadily increasing need for cooling is to be observed, for example in the field of intercooling, whereby the demands on the cooling and air conditioning systems steadily increase. Improved utilization of heat sources and heat sinks can lead to a higher degree of utilization and, moreover, to a reduction in fuel consumption. Cooling systems for intercooling currently available on the market often have a stacked-plate heat exchanger which has a single-stage design. However, the achievable with the single-stage temperature efficiency is limited. In order to improve the performance of cooling circuits, in particular for cooling fluids, such as, for example, coolant, refrigerant, oil, exhaust gas or charge air, it is therefore appropriate in some cases to cool or heat a fluid over two stages. A disadvantage of the two-stage temperature control of fluids is, however, that the use of two conventionally connected in series heat exchangers is associated with significantly higher costs and increased space requirements.

From DE 10 2005 044 291 A1 discloses a stacked plate heat exchanger, in particular a charge air cooler, with a plurality of stacked and interconnected, for example, soldered, elongated panes known, which has a cavity for carrying a medium to be cooled, such as charge air in the longitudinal direction Limiting discs and another cavity for carrying a coolant, wherein the discs each have an input port and an output port for the medium to be cooled. Around To create a stacked plate heat exchanger, on the one hand is inexpensive to produce and on the other hand, even at high temperatures has a long life, at least one coolant connection extends partially around a connection for the medium to be cooled around.

The invention is concerned with the problem of providing a stacked-plate heat exchanger of the generic type an improved embodiment, which allows a two-stage temperature control of a medium to be cooled with a compact design.

This problem is solved according to the invention by the subject matter of independent claim 1. Advantageous embodiments are the subject of the dependent claims.

The present invention is based on the general idea to provide on individual heat exchanger plates of a stacked plate heat exchanger, an embossed partition, which is molded simultaneously with the heat exchanger plate and which serves to separate a high-temperature coolant circuit and a low-temperature coolant circuit from each other, but at the same time allows these two circuits to run in a common stacked plate heat exchanger. The stacked-plate heat exchanger according to the invention, which may be designed, for example, as a charge air cooler, has said high-temperature coolant circuit and the aforementioned low-temperature coolant circuit, wherein the stacked heat exchanger plates of two coolants with different temperature levels in the high-temperature coolant circuit and in the low-temperature coolant circuit on the one hand and are flowed through by the medium to be cooled, for example, charge air, on the other hand. With the stacked-plate heat exchanger according to the invention, it is now possible to use a two-stage timer. in a lone stacked plate heat exchanger summarize and thus to achieve an extremely compact solution.

Suitably, the stacked plate heat exchanger is designed as a counterflow cooler. In a counterflow cooler, the coolant and the medium to be cooled flow opposite to each other, whereby a particularly effective cooling can be achieved. When cooling in the counterflow principle, the cooling effect is generally greater than in the case of the same flow directions.

Expediently, the heat exchanger plates have a circumferential raised edge over which they are soldered to an adjacent, in particular one or above, arranged heat exchanger plate, wherein the partition is connected in each case along the end side with the edge. The partition thus passes through the respective heat exchanger plate in the transverse direction and is connected at one end at one edge and at the other end at the opposite edge. Such a heat exchanger plate usually has the shape of a rectangle, the narrow sides, however, are rounded in a semicircle. The partition wall preferably runs centrally, but can be moved in almost any desired manner in accordance with the required cooling capacity of the low-temperature coolant circuit or the high-temperature coolant circuit in the longitudinal direction of that heat exchanger plate. As a result, the cooling capacity of the two circuits is adjustable. The arrangement of the partition wall is comparatively easily adjustable by the corresponding positioning of a separating web in the punching tool.

In an advantageous development of the solution according to the invention, a coolant inlet and / or a coolant outlet is / is provided in the region of the connection of the partition wall to the edge. Usually, the two semicircular rounded Längsendbereiche each heat exchanger plate also have a semi-circular opening for the medium to be cooled, wherein the one opening is designed as an inlet opening and the other opening is designed as an outlet opening. In this case, coolant channels are arranged in the manner of a ring segment around the respective inlet or outlet opening. A flow through the stacked plate heat exchanger takes place from the medium to be cooled in that it first through the inlet opening (medium inlet) and then flows through the individual heat exchanger plates in the longitudinal direction, at the opposite end again deflected by 90 degrees and via the outlet opening (Me-). diumauslass) to be discharged. The coolant required for the exchange of heat, on the other hand, flows in, for example, in the low-temperature circuit via the coolant inlet arranged in the manner of a ring segment and out again via two coolant outlets arranged in the region of the dividing wall. In the high-temperature circuit, the coolant flows through two arranged in the region of the partition coolant inlets, through the heat exchanger plate and through the ring segment-like arranged coolant outlets again. The flow direction of the coolant is in both circuits opposite to that of the medium to be cooled, for example, the charge air in order to realize the countercurrent principle.

The coolant inlets and / or coolant outlets may have a triangular cross section and their legs may be aligned parallel to the partition wall and the edge. Of course, in a particularly preferred embodiment, the cross section of the coolant inlet or of the coolant outlet is a right-angled triangle, as a result of which the two catheters of the respective coolant inlet or coolant outlet run parallel to the partition wall or to the edge. Such a cross section of the coolant inlet or of the coolant outlet is comparatively easy to produce with a corresponding punching tool, wherein, of course, the corner regions of the cross sections are rounded in order in particular to be able to reduce a notch effect. Depending on how long the respective leg of the triangular coolant inlet or coolant outlet along the Dividing wall extends, influence can be taken on the continuous for the charge air or the medium to be cooled cross-section. The smaller the leg length of the coolant inlet or of the coolant outlet extending along the dividing wall, the greater is the flow cross section for the medium to be cooled (charge air), as a result of which lower pressure losses on the charge air side can be achieved. Of course, the leg length of the coolant inlet or of the coolant outlet along the dividing wall on the high-temperature side may be greater than on the low-temperature side, whereby an optimized charge air distribution can be achieved on the low-temperature side and increased cooling performance can be achieved.

Other important features and advantages of the invention will become apparent from the dependent claims, from the drawings and from the associated figure description with reference to the drawings.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination given, but also in other combinations or in isolation, without departing from the scope of the present invention.

Preferred embodiments of the invention are illustrated in the drawings and will be described in more detail in the following description, wherein like reference numerals refer to the same or similar or functionally identical components.

Show, in each case schematically,

1 is a sectional view through a stacked plate heat exchanger according to the invention, 2 is a view of a heat exchanger plate of the stacked plate heat exchanger,

3 shows detailed views of a coolant inlet or coolant outlet of two adjacent heat exchanger plates

Fig. 4 is a representation as in Figure 2, but in a plane of a medium to be cooled

Fig. 5a-d different pronounced cross sections of a in the area of a

Partition disposed coolant inlet or coolant outlet,

6a-c different interconnections of the charge air flow in the stacked plate heat exchanger according to the invention,

Fig. 6 d-e different interconnections of the coolant flows in the stacked plate heat exchanger according to the invention.

Corresponding to FIG. 1, a stacked-plate heat exchanger 1 according to the invention, which is embodied, for example, as a charge air cooler, has a high-temperature coolant circuit HT and a low-temperature coolant circuit NT with heat exchanger plates 2 stacked on top of each other and through which two coolants 3, 4 with different temperature levels flow. The coolant 3 flows in comparison with the coolant 4 higher temperature level in the high-temperature coolant circuit HT, whereas the coolant 4 flows at a significantly lower temperature level in the low-temperature coolant circuit NT. In the opposite direction, the stacked plate heat exchanger 1 of the invention is to be cooled by the 5, for example, charge air, flows through, so that the stacked plate heat exchanger 1 operates in countercurrent principle.

In order to effectively separate the high-temperature coolant circuit HT from the low-temperature coolant circuit NT and at the same time be able to accommodate both circuits HT and NT in the same stacked plate heat exchanger 1, the heat exchanger plates 2 an embossed partition 6 (see Figures 2 to 6), the separates the high-temperature coolant circuit HT from the low-temperature coolant circuit NT.

In addition, all the heat exchanger plates 2 have a peripherally erected edge 7, via which they are soldered to an adjacent, for example, a heat exchanger plate 2 arranged below or above, wherein the partition wall 6 is connected to the edge 7 at the longitudinal end. The partition 6 can meet orthogonally on the respective edge 7, as shown for example according to the embodiments Figures 2 to 5b and 5d and 6. Alternatively, it is also conceivable that the partition wall 6 meets at an acute angle to the edge 7, as shown for example in accordance with the figure 5c.

In the area of the connection of the partition wall 6 to the edge 7, a coolant inlet 8 and / or a coolant outlet 9 are arranged. According to the embodiments of FIGS. 1 to 5c, the coolant inlets 8 and / or the coolant outlets 9 have a triangular, ie triangular, cross section and are parallel with the dividing wall 6 and with their legs X at their legs Y (compare FIGS. 5a to 5c) Aligned edge 7. The parallel to the partition wall 6 aligned leg Y of the triangular coolant inlet 8 or the coolant outlet 9 may be longer or shorter than the aligned parallel to the edge 7 leg X, which of course is also conceivable that both legs X, Y of the triangular Coolant inlet 8 or the triangular coolant outlet 9 are the same length. In contrast, the edge 7 according to the figure 5d in the region of the partition wall 6 a bulge to the outside, whereby the coolant inlet 8 and the coolant outlet 9 have an at least approximately circular segment-like cross section and are offset to the outside.

In the following, the flow through the stacked-plate heat exchanger 1 according to the invention will now be explained in more detail.

According to FIG. 1, the medium 5 to be cooled, for example the charge air, flows from a medium inlet 10 through the heat exchanger plates 2 to a medium outlet 11 in a substantially U-shape through the stacked plate heat exchanger 1. In the opposite direction flows the low-temperature coolant circuit NT and the high-temperature coolant circuit HT. The coolant 4 first flows through a coolant inlet 8 'over approximately half of the heat exchanger plates 2 to the coolant outlet 9 located in the region of the partition wall 6, two coolant outlets 9 being arranged on the dividing wall 6 (cf. FIG. 2), while the coolant inlet 8' is arranged. ringseg- ment arranged around the medium outlet 1 1. About the coolant inlet 8, the coolant 3 flows to the partition wall 6 through the high-temperature coolant circuit HT through also about half of the heat exchanger plate 2 to the coolant outlet 9 ', which extends like a ring segment around the medium inlet 10.

In the embodiments according to FIGS. 1 to 6, the partition wall 6 is substantially centered but slightly displaced in the direction of the high-temperature coolant circuit HT, whereby the high-temperature coolant circuit HT has a shorter heat-transferring contact between the medium 5 to be cooled and the coolant 3 , To improve the heat transfer, of course, turbulence inserts 12 may be used. will see. A displacement of the partition wall 6 can be achieved by a simple variation or displacement of a corresponding separating web in the associated punching tool for the production of the heat exchanger plates 2. Of course, winglets or a corrugated rib structure can also be used to improve the heat transfer.

Looking at FIG. 5a, it can be seen that the leg X extending parallel to the edge 7 is made longer than the leg Y of the coolant outlet 9 running parallel to the dividing wall 6, thereby increasing a width Z of the passage cross-section available for the charge air and thus the pressure loss on the charge air side can be reduced.

On the other hand, the coolant outlet 9 according to FIG. 5 b is provided with a significantly reduced limb length of the leg Y parallel to the dividing wall 6, while the coolant inlet 8 on the high-temperature side, i. in the high-temperature coolant circuit HT has a comparatively longer leg Y for this purpose. As a result, for the medium to be cooled 5, i. the charge air, provided on the low temperature side NT a greater width Z of the available flow cross-section, whereby the flow rate on the low temperature side NT compared to the high temperature side HT decreases and the low temperature side cooling capacity can be increased.

FIG. 5c shows a dividing wall 6 which occurs at an acute angle to the edge 7, wherein the dividing wall 6 is angled. The coolant outlet 9 is displaced in the direction of the low-temperature side NT, wherein due to the angled partition 6 with the same cross-section, a larger for the medium to be cooled 5, ie the charge air, available flow cross-section can be provided (greater width Z), which also a lower pressure drop on the charge air side can be achieved. In the heat exchanger plate 2 according to FIG. 5d, the coolant inlet 8 and the coolant outlet 9 are displaced outwards, whereby the complete width of the heat exchanger plate 2 (width = Z) is available for the medium 5 to be cooled, ie for the charge air. In this case, the edge 7 of the heat exchanger plate 2 is curved in the region of the partition wall 6 to the outside and the coolant inlet 8 and the coolant outlet 9 have an at least approximately circular segment-like cross section. As a result, the smallest possible pressure loss on the charge air side can be achieved.

Corresponding to FIGS. 6a to 6c, possible interconnections on the charge air side, i. shown in the flow path of the medium to be cooled 5, the variants shown are of course also mirrored possible. According to FIG. 6a, the stacked plate heat exchanger 1 is designed in such a way that it flows through the medium 5 to be cooled, for example the charge air, in a U-shaped manner. According to FIG. 6b, this takes place in a Z-shaped manner, whereas according to FIG. 6c, it takes place in a double U-shape.

In Figures 6d-f, possible interconnections on the coolant side, i. represented for the two coolant flows 3.4, which of course also in this case mirrored variants are conceivable. According to FIG. 6d, a flow through the high-temperature coolant circuit HT by means of the coolant 3 is U-shaped, just as the coolant 4 flows through the low-temperature side NT in a U-shaped manner. In an analogous manner, this is Z-shaped according to the figure 6e or double U-shaped according to the figure 6f. Of course, the illustrated variants of the charge air side and the coolant side can be combined with one another in any desired manner, whereby a direct current variant (not shown) is also conceivable theoretically.

With the stacked-plate heat exchanger 1 according to the invention, a compact two-stage heat exchanger can be created, on the one hand Space advantages and on the other hand, an optimized cooling can be achieved.

*****

Claims

claims

1 . Stacked plate heat exchanger (1), in particular a charge air cooler, with a high-temperature coolant circuit (HT) and a low-temperature coolant circuit (NT), with heat exchanger plates (2) stacked on top of each other, which are cooled by two coolants (3,4) with different temperature levels in the high-temperature Coolant circuit (HT) and in the low-temperature coolant circuit (NT) on the one hand and a medium to be cooled (5), in particular charge air, on the other hand are flowed through,

characterized,

the heat exchanger plates (2) have an embossed partition wall (6) for separating the high-temperature coolant circuit (HT) and the low-temperature coolant circuit (NT).

2. stacked plate heat exchanger according to claim 1,

characterized,

the stacked plate heat exchanger (1) is designed as a countercurrent cooler.

3. stacked plate heat exchanger according to claim 1 or 2,

characterized,

in that the heat exchanger plates (2) have an encircling raised edge (7), via which they are soldered to an adjacent heat exchanger plate (2), wherein the dividing wall (6) is connected to a rim (7) at the longitudinal end.

4. stacked plate heat exchanger claim 3,

characterized,

that the dividing wall (6) meets the edge (7) orthogonally or at an acute angle.

5. stacked plate heat exchanger according to claim 3 or 4,

characterized,

in that at least one coolant inlet (8) or one coolant outlet (9) is arranged in the region of the connection of the dividing wall (6) to the edge (7).

6. stacked plate heat exchanger according to claim 5,

characterized,

in that the coolant inlet (8) and / or the coolant outlet (9) have a triangular cross-section and are aligned with their legs (Y) parallel to the dividing wall (6) and with their legs (X) parallel to the edge (7).

7. stacked plate heat exchanger according to claim 6,

characterized,

- That the parallel to the partition (6) aligned leg (Y) of the triangular coolant inlet (8) or coolant outlet (9) is longer or shorter than the parallel to the edge (7) aligned leg (X) of the triangular coolant inlet (8) or coolant outlet (9), or

- That both legs (X, Y) of the triangular coolant inlet (8) or coolant outlet (9) are the same length.

8. stacked plate heat exchanger according to claim 5,

characterized,

the edge (7) of the heat exchanger plate (2) is arched outwards in the area of the dividing wall (6) and the coolant inlet (8) and / or the coolant outlet (9) have an at least approximately circular segment-like cross section.

9. stacked plate heat exchanger according to one of claims 1 to 8, characterized

the stacked-plate heat exchanger (1) is designed such that it flows through the medium to be cooled (5), for example the charge air, U-shaped, Z-shaped or double U-shaped.

10. stacked plate heat exchanger according to one of claims 1 to 9, characterized

- That the stacking plate heat exchanger (1) is designed such that the coolant (3) flows through the high-temperature coolant circuit (HT), U-shaped, Z-shaped or double U-shaped, and / or

- That the stacking plate heat exchanger (1) is designed such that the coolant (4) flows through the low-temperature coolant circuit (NT) U-shaped, Z-shaped or double U-shaped.