HEAT EXCHANGER

Abstract

The invention relates to a heat exchanger in which a liquid coolant and a gaseous flow, for example compressed charge air, are involved in the exchange of heat, with at least two heat exchanger blocks being provided which can be traversed by the coolant and by the gaseous flow. The invention can include inventive solutions for a flat arrangement including at least one gas-side bypass arranged adjacent to or within the first heat exchanger block and/or adjacent to or within the second heat exchanger block. The present invention also provides a method for cooling that divides the gaseous flow into at least two partial flows. One partial flow can be guided past a heat exchanger block, and the other partial flow can be conducted through the other heat exchanger block before the partial flows are finally merged.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is perspective view of a heat exchanger according to a first exemplary embodiment of the present invention.

FIG. 2 shows a partial perspective view of the heat exchanger shown in FIG. 1.

FIGS. 3 and 4 show a heat exchanger according to a second exemplary embodiment.

FIGS. 5 and 6 show a heat exchanger according to a third exemplary embodiment.

FIG. 7 is an exploded perspective view of a heat exchanger block of the present invention.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings.

The heat exchanger arrangements shown and described below could also be used in other applications, such as, for example, as an exhaust gas heat exchanger in motor vehicles. Alternatively or in addition, the heat exchanger arrangements could be used for any other desired purpose which is dependent on the lowest possible pressure loss, for example, on the gas side and which are constructed with a relatively flat design.

The depicted heat exchanger arrangements represent charge air coolers and are thus referred to as such below. In the charge air cooler, the compressed charge air is cooled by a cooling liquid of the engine of a utility vehicle. In FIG. 1, the charge air is shown by solid arrows and the cooling liquid is shown by dashed arrows. The charge air cooler is of flat construction, because it should be fastened (not shown) to the underside of the drive unit of a utility vehicle. For this purpose, the charge air cooler is equipped with a plurality of connectors 10. Illustrated are four cantilevers which have bores at their ends.

The charge air cooler has a housing G in which are situated two heat exchanger blocks A and B. The first heat exchanger block A as viewed in the flow direction of the charge air is arranged slightly lower than the second heat exchanger block B. Situated above the first heat exchanger block A is a bypass C. Situated below the second heat exchanger block B is a further bypass C.

The compressed and heated charge air entering through the inlet is, in this exemplary embodiment, divided into two partial flows. The first partial flow passes through the first bypass C and the second partial flow flows through the first heat exchanger block A. The second partial flow leaving the first heat exchanger block A has correspondingly been cooled and flows via the second bypass C in the direction of the outlet. It is possible for insulation to be provided therein in order to prevent the partial flow being heated again. The first partial flow passing from the first bypass passes through the second heat exchanger block B in order to likewise be cooled.

Downstream of the second heat exchanger block B, the two partial flows are merged and are made available as a cooled charge air flow, which has been only slightly reduced through pressure loss, for charging the internal combustion engine (not shown). A cross section which is drawn in FIG. 1 can also effectively demonstrate the above-described substantive matter with regard to the working method carried out with the arrangement. In the illustrated embodiments, the inlets and outlets are constructed as relatively smooth-walled tubes which can generate only a negligible pressure loss. The interior of the heat exchanger blocks A and B is designed so as to generate a division into partial flows.

The heat exchanger blocks A and B can be of substantially identical design. Situated between the two heat exchanger blocks A and B is a guide device D which provides the described guidance of the partial flows. The guide device D is of a flow-promoting shape. In the exemplary embodiment, both heat exchanger blocks A and B are traversed in series at the liquid side by the cooling liquid, as is intended to be indicated by the dashed lines. Because, in the exemplary embodiment, all of the inlets and outlets for the cooling liquid are situated on one side, it is clear that each heat exchanger block A and B is traversed by the cooling liquid in a U-shape, while the charge air can flow transversely with respect thereto but on a straight path through the heat exchanger blocks A and B. In FIG. 2, the U-shaped throughflow has been indicated at the heat exchanger block B. Here, only one “U” has been indicated. It is however also possible for multiple U-shaped loops, that is to say a meandering flow, to be provided.

In contrast to the described exemplary embodiment, the heat exchanger blocks A and B in FIGS. 3 and 4 are situated at a common height, and the bypasses C have been arranged at opposite ends of the heat exchanger blocks A, B. A guide device D is provided between the blocks A and B.

In the exemplary embodiment shown in FIGS. 5 and 6, three partial flows are provided on the charge air side. With the selected throughflow, the charge air passes through two bypasses C which are situated at the outside of the first heat exchanger block A, and through a bypass C which is situated at the inside of the second heat exchanger block B. The throughflow direction can be selected both on the charge air side and also on the liquid side. The first heat exchanger block A is situated approximately at a central region in the housing G in which the one bypass C is also situated. The second heat exchanger block B, which could also be composed of two heat exchanger blocks, is situated in the two outer regions in the housing G in which the two bypasses C are situated. The guide device D is composed here of two walls, as the figures show. The exemplary embodiments shown already reveal that at least some further variations of the arrangement of heat exchanger blocks and bypasses, which have all of the steps of the working method, are possible and appear to be expedient. For example, it is also possible for more than two heat exchanger blocks to be arranged in series in the flow direction of the charge air.

FIG. 7 shows a partially exploded illustration of a heat exchanger block which is suitable for the proposed arrangement. The heat exchanger block is composed of heat exchanger plates 2 which form in each case one pair. At the opposite ends, each plate pair in the exemplary embodiment shown is closed off by inserted rods 3 and 4. At the longitudinal sides, the plates 2 are provided with shaped edge flanges in order to close off the space within a plate pair.

The cooling liquid flows within each pair. The plates 2 are formed with beads 7 or similar formations in such a way that the cooling liquid must pass through a plurality of U-shaped paths in order to pass from the inlet to the outlet. Arranged between the pairs are corrugated fins 5 or similar elements, through which one partial flow of the charge air flows. The block arrow is intended to show this. The stack of plates 2 and corrugated fins 5 is provided at the top and at the bottom with one closure plate 1, 6 which are formed to be slightly more stable than the other plates 2. Blocks of this type can be arranged within the housing G which is shown. It is however also possible to use blocks of some other design, which need not strictly be situated in a housing G which is closed off at all sides. It is also possible for one block to be arranged in a housing G and for the other block to be designed to be of the housingless type.

Various features and advantages of the invention are set forth in the following claims.

Claims

1. A heat exchanger for transferring heat between a liquid coolant flow and a gaseous flow, the heat exchanger comprising: a pair of heat exchanger blocks being traversed by the coolant flow and the gaseous flow;a gas bypass arranged adjacent to or within the first heat exchanger block; anda gas bypass arranged adjacent to or within the second heat exchanger block, a first partial flow of the gaseous flow being directed through the gas bypass of the first heat exchanger and a second partial flow of the gaseous flow being directed through the gas bypass of the second heat exchanger.

2. The heat exchanger of claim 1, wherein one bypass is arranged at one side of the first heat exchanger block, and wherein an other bypass is situated at an opposite side of the second heat exchanger block.

3. The heat exchanger of claim 1, wherein one bypass is arranged at a side of the first heat exchanger block and an other bypass is situated at a corresponding side of the second heat exchanger block.

4. The heat exchanger of claim 1, wherein the heat exchanger blocks are arranged so as to be offset in height with respect to a flow direction of the gaseous flow.

5. The heat exchanger of claim 1, wherein the heat exchanger blocks are arranged at a common height with respect to a flow direction of the gaseous flow.

6. The heat exchanger of claim 1, wherein the blocks are spaced apart, and wherein at least one guide for conducting the first and second partial flows extends through the space between the heat exchanger blocks.

7. The heat exchanger of claim 1, wherein the blocks bear directly against one another and have different heights, and wherein one of the bypasses is arranged at least on or in the flatter block.

8. The heat exchanger of claim 1, wherein insulation can be provided between the bypass and one of the pair of the heat exchanger blocks.

9. A method of transferring heat between a gaseous flow and a liquid coolant in a heat exchanger having at least two heat exchanger blocks, the method comprising the acts of: dividing the gaseous flow into at least two partial flows;directing a first partial flow through one of the two heat exchanger blocks;directing a second partial flow through another of the two heat exchanger block; andmerging the one and the other partial flows.

10. The method of claim 9, wherein the first partial flow is guided past a first one of the pair of heat exchanger blocks, wherein the second partial flow is conducted through the first heat exchanger block, wherein the first and second partial flows are conducted through the second heat exchanger block, and wherein the first and second partial flows are merged either at the second heat exchanger block or downstream therefrom.

11. The method of claim 9, wherein the second partial flow is directed past the first heat exchange block, and wherein the first partial flow is directed past the second heat exchanger block through the second heat exchanger block, and wherein another partial flow is guided past the second heat exchanger block before being merged with the second partial flow.

12. The method of claim 9, wherein the coolant flow is initially conducted into the second heat exchanger block and subsequently into the first heat exchanger block.

13. The method of claim 9, wherein the coolant flow is initially conducted into the first heat exchanger block and subsequently into the second heat exchanger block.

14. The method of claim 9, wherein the coolant flow which flows through the one of the two heat exchanger blocks belongs to a different circuit than the coolant flow which flows through the other of the two heat exchanger blocks.

15. The method of claim 14, wherein the coolant which flows through the one of the two heat exchanger block being different than the coolant flow which flows through the other of the two heat exchanger blocks.

16. The method of claim 14, wherein the coolant which flows through the one of the two heat exchanger block being the same as the coolant flow which flows through the other of the two heat exchanger blocks.