FR2846734A1 - Motor vehicle heat exchanger module has stacked plates defining fluid flow paths and with partition to separate heat exchange regions - Google Patents

Abstract

The motor vehicle heat exchanger module has multiple plates (2,4) which are stacked and assembled to define flow passages for a first fluid (F1) which alternate with passages for a second fluid (F2). There is a partition (14) to separate the module into independent heat exchange sections (10,12). One of the fluids is atmospheric air. Claims include a motor vehicle heat exchanger circuit using the module.

Description

Plate heat exchanger module having an exchange section

  The invention relates to heat exchange modules, in particular for motor vehicles. More particularly, it relates to a heat exchange module having a multiplicity of stacked plates, assembled to determine first flow channels for a first fluid, which alternate with second flow channels for a second fluid. Already known (DE-A-195 11 991 and EP 1 063 486) stacked plate heat exchangers used, for example, as oil coolers for motor vehicles, for cooling the engine oil and / or the automatic gearbox, by heat exchange with a cooling fluid, usually that used for

  engine cooling of the vehicle.

  However, in plate heat exchangers of this type, the plates are grouped in a single stage, which does not make it possible to cool or sufficiently heat a fluid because the inlet temperature of the second fluid, with which it is heat exchange relationship, is not sufficiently low, respectively sufficiently high. Furthermore, it is possible that the thermal power available on one of the fluids is not sufficient to ensure cooling,

  respectively the heating of a fluid.

  The present invention relates to a heat exchange module that overcomes these disadvantages. To this end, it proposes a heat exchange module of the type defined above which comprises at least one partition wall which divides the heat exchange module into at least two independent or non-independent heat exchange sections. at least one of the fluids circulating in the heat exchange sections being constituted by a flow of atmospheric air. When the two heat exchange sections are independent, a heat exchange module is formed consisting of two independent exchangers, one of these 10 exchangers being cooled, for example, by a fluid, while the second is cooled. by a circulation of atmospheric air. This feature reduces the size of the heat exchange module in the engine compartment of the vehicle. In a preferred embodiment, at least one of the partition walls adjacent to the heat exchange section in which the flow of atmospheric air circulates comprises a communication passageway permitting the passage of one of the circulating fluids. in the heat exchange section

  located on the other side of the partition wall having the communication passages in the heat exchange section in which the air flow circulates, in order to achieve a heat exchange between this fluid and the air flow 25 atmospheric.

  With this characteristic, if the heat exchange with one or more liquid fluids is not sufficient to cool (possibly to heat> a given fluid, a complementary heat exchange with a stream of atmospheric air makes it possible to complete the cooling, possibly the

warming of this fluid.

  In a particular embodiment, the plates of at least one of the heat exchange sections are provided with raised peripheral edges, sealingly assembled to define the first and second flow channels.

flow channels.

  Advantageously, the plates of the heat exchange section 5 in which the flow of atmospheric air circulates define first flow channels for a fluid alternating with second open flow channels for the circulation of the air flow. Corrugated inserts can be arranged between

  heat exchange section plates which define open flow channels for the flow of air.

  Advantageously, the module may comprise an air inlet nozzle 15 for channeling the flow of air towards the plates of the heat exchange section in which the flow of atmospheric air circulates, and an outlet nozzle of air to channel the flow of air at the outlet of the heat exchange section in which circulates the flow of atmospheric air. Finally, the invention relates to an air conditioning circuit, in particular of the passenger compartment of a motor vehicle, comprising an evaporator, a compressor, a condenser, an expansion valve, in which a cooling fluid circulates, the condenser being constituted by a two-way heat exchanger

  heat exchange sections according to the present invention.

  Other characteristics and advantages of the invention will become apparent on reading the description which follows of exemplary embodiments given for illustrative purposes.

  reference to the appended figures. In these figures: - Figure 1 is a schematic sectional view of a two-stage heat exchange module according to the present invention; Figure 2 is a fragmentary sectional view - Figure 3 - Figure 4 - enlarged Figure 5 of the heat exchange module shown in Figure 1; is a schematic sectional view of a second embodiment of a two-stage heat exchange module according to the present invention; is a schematic view of the front portion of a motor vehicle;

  is a magnifying glass that represents an enlargement of the portion surrounded by dashed lines of the engine hood of the vehicle of Figure 4; is a magnifying glass that represents an enlarged view showing a variant of the implementation of a condenser according to the invention in a motor vehicle.

  - Figure 6 is shown in Figure 1 a sectional view of a heat exchange module according to the invention. It is divided into a first heat exchange section designated by the general reference 10 and a second heat exchange section designated by the general reference 12. The heat exchange sections 10 and 12 are separated by a plate 14. Only the fluid to be cooled or heated

in both sections.

  The heat exchange section 10 consists of plates 2

  stacked on top of each other and each provided with a peripheral rim 3. The peripheral flanges 3 are assembled in a sealed manner to delimit between the plates 2 of first flow channels for a first fluid F1 which alternate with second fluid channels. flow for a second fluid F2.

  The heat exchange section 12 is constituted by a stack of plates 4 which are distinguished from the plates 2 of the heat exchange section 10 in that they do not comprise inclined flange 3. These plates are designed in order to determine first flow channels for the circulation of a first fluid, generally a liquid, and second channels having an open inlet and an outlet for the entry of an air flow, as shown schematically by the arrows 5 (Figure 2) and for the output of this flow, as shown schematically by the arrow 6. In Figure 1, there is shown only an inlet pipe 15 for the first fluid F1 and only an outlet pipe 17 for the second fluid F2. However, it is understood that four pipes are actually provided on the end plate 19 of the heat exchange module, namely an inlet pipe 15 for the first fluid F1 and an outlet pipe for this same fluid, located behind the tubing 15. This output tubing is not visible in the figure. Similarly, an inlet pipe and an outlet pipe 17 are provided for the second fluid F2. The fluid inlet tubing F2 is located behind the outlet tubing 17. It is not visible in Figure 1. Alternatively, the fluid outlet Fl may be on the other side of the module as shown. by tubing 16 shown in broken lines. The heat exchange sections 10 and 12 may be independent of each other. In this case, the partition wall 14 disposed between these two sections has no communication passage for the fluids flowing in these different sections. Two independent heat exchangers are thus determined, the first heat exchanger, corresponding to the heat exchange section 10, being cooled by a fluid-fluid circulation, while the second heat exchanger, corresponding to the heat exchange section, heat 12, is cooled by a circulation of one

  flow of atmospheric air outside.

  Advantageously, the heat exchange section 12 comprises an air inlet nozzle 7 which makes it possible to channel the flow of air towards the plates 4 of the section 12 and an air outlet nozzle 9 which makes it possible to channel the flow of air at the outlet of the plates 4. Thus, the fluids Fi and F2 circulate in the heat exchange section 10 in heat exchange relationship with each other. In the example shown, the heat exchange module is a condenser used to condense the cooling fluid of the air conditioning circuit of the motor vehicle, for example R134a or carbon dioxide. The fluid F1 is constituted by the cooling fluid of the air conditioning circuit, whereas the fluid F2 is a liquid,

  usually the water of the engine cooling circuit.

  In the example shown, the heat exchange sections 10 and 12 are not independent of each other. This is why the partition wall 14 has two communication passages 21 respectively located opposite the inlet pipe 15 of the refrigerant of the air conditioning circuit 20 and the outlet pipe of the same fluid. The partition wall does not have a communication passage at the

  view of the inlet and outlet pipes of fluid F2.

  Thus, only the cooling fluid F1 of the air-conditioning circuit can enter the heat-exchange section 12 through the communication passage 21 located at the right of the inlet manifold 15. Having reached this section 12, it circulates in the first flow channels delimited between the plates 4 of the section 12 in heat exchange relation 30 with the atmospheric air circulating in the second channels

  defined by the same flow plates 4. After having passed through the flow channels, the fluid F leaves the heat exchange section 12 by the second communication passage 21 situated opposite the outlet pipe (no 35 shown and not referenced) of the fluid F1.

  A two-stage and three-fluid heat exchange module is thus produced. In the first stage, corresponding to the heat exchange section 10, the cooling fluid of the air conditioning circuit is cooled by heat exchange 5 with the fluid F2, then, in the second stage, corresponding to

  the heat exchange section 12, by heat exchange with the atmospheric air flow. The presence of the second stage makes it possible to complete the cooling of the cooling fluid in the case where its cooling is not sufficiently ensured by the exchange of heat with the second fluid F2.

  Of course, the heat exchange module of the invention may comprise only one pass or, in known manner, it may comprise a plurality of passes. Advantageously, the partition wall 14 may be constituted by a current plate 2 of the heat exchange section 10, or by a current plate 4 of the section

heat exchange 12.

  FIG. 3 is a diagrammatic sectional view of another exemplary embodiment of a heat exchange module according to the invention. It comprises a first heat exchange section 10 and a second heat exchange section 12 separated by a partition wall

  14. In Figure 3, the section is taken through the fluid inlet pipe F2, designated by the reference 23, and the outlet pipe 17 of the same fluid F2. The inlet and outlet tubings of the first fluid F1 are not shown.

  This embodiment is distinguished by the different constitution of the plates 25 of the heat exchange section 12. The plates 25 are grouped in pairs. Plates of the same pair have cups 27 facing towards each other and sealingly connected to each other at their periphery. The bottoms of these cups 27 communicate through openings 29, so as to delimit circulation chambers 31 for the liquid fluid of the heat exchange section 12. Furthermore, the plates 25 delimit between them circulation passages 33 for the airflow

  In this embodiment, it is noted that the flow of air 35 flows perpendicularly to the circulation of the other fluid, and not to the countercurrent or concurrent. Preferably, corrugated spacers 37 are disposed in the circulation passages 33 of the atmospheric air stream 35.

  The operation of this second exemplary embodiment is similar to that of the heat exchange module which has been described with reference to FIGS. 1 and 2. The refrigerant fluid F1 of the air conditioning circuit circulates in the first heat exchange section. 10 in heat exchange relation with the fluid F2, generally the cooling water of the engine, then passes into the heat exchange section 12 by communication passages formed in the separating plate 14 in order to flow in heat exchange relationship with the atmospheric air stream 35 to lower even further

its temperature.

  Although, in FIG. 3, the circulation chambers 31 have been represented opposite the fluid circulation chambers F2, in reality, the communication chambers are opposite the inlet and outlet pipes,

respectively, of the fluid F1.

  FIG. 4 shows a schematic view of the

  the front part of a motor vehicle 40. The circle represented in dashed lines 41 surrounds an area 42 located under the engine bonnet 43 of the motor vehicle, in which it is possible to implement a multi-stage and multi-stage heat exchange module. fluids according to the present invention.

  FIG. 5 is a magnifying glass which represents on an enlarged scale the area surrounded by the dashed circle 41 of FIG. 4. The heat exchange module of the invention, designated by the general reference 45, consists of two stages. i.e. a first stage constituted by the heat exchange section 10, cooled by the cooling water of the cooling circuit of the engine of the vehicle, and a second stage constituted by the heat exchange section 12, cooled by a circulation of atmospheric air. Arrow 46 denotes the entry of air into a duct 47, while the

  arrow 48 symbolizes the exit of the air from a duct 49 after crossing the heat exchange section 12. A fan 50 may possibly provide forced circulation of air.

  Reference 52 denotes the evaporator of the air conditioning circuit. The air flow 54 is cooled, prior to entering the passenger compartment of the vehicle, through the crossing of

the evaporator 52.

  FIG. 6 shows a magnifying glass similar to that of FIG. 5. In this embodiment, the implantation of the heat exchange module 45 of the invention differs in that the air outlet nozzle 54 opens into the engine compartment 53 of the vehicle (arrow 57) instead of being rejected to the outside (arrow 48 of Figure 5). 25

Claims (8)

claims   A heat exchange module comprising a multiplicity of stacked plates (2, 4), assembled to delimit first flow channels for a first fluid (F1) which alternate with second flow channels for a second fluid (F2), characterized in that it comprises at least one partition wall (14) which divides the heat exchange module into at least two heat exchange sections (10, 12) independent or not, at least one of the fluids (F1, F2) flowing in the heat exchange sections (10, 12) being constituted by an atmospheric air flow (5).   2. Heat exchange module according to claim 1, characterized in that at least one of the partition walls (14) adjacent to the heat exchange section (12) in which circulates the air flow 5, 6) has communication passages (21) for the passage of one of the fluids (F1) flowing in the heat exchange section (10) on the other side of the partition wall. separation (14) comprising the communication passages (21) in the heat exchange section (12) in which the air flow (5, 6) flows in order to achieve a heat exchange between this fluid (F1) and the flow of atmospheric air (5, 6). 25   3. Heat exchange module according to one of claims 1 or 2, characterized in that the plates (2) of at least one of the heat exchange sections (10) are provided with flanges   devices (3) raised, assembled tightly. 30   Heat exchange module according to one of Claims 1 to 3, characterized in that the plates (4) of the heat exchange section (12) in which the flow of atmospheric air (5, 6) delimit first flow channels 35 for a fluid (F1) alternating with second channels   open flow for the flow of air (5, 6).   he 5. Heat exchange module according to claim 4, characterized in that corrugated inserts (37) are arranged between the plates (25) of the heat exchange section (12) which define open channels for circulation. air flow (35).   6. heat exchange module according to one of claims 1 to 5, characterized in that it comprises an inlet nozzle (7) for channeling the air flow (5) to the plates (4) of the heat exchange section (12) in which the flow flows   of air, and an outlet nozzle (9) for channeling the air flow (6) to the outlet of the plates (4) of the exchange section of   heat (12) in which circulates the same air flow.   7. Heat exchange module according to one of the claims   1 to 6, characterized in that the partition walls (14) are constituted by common plates (2, 4) of the sections heat exchange (10, 12).   8. Air conditioning circuit, in particular of the passenger compartment of a motor vehicle, comprising an evaporator (52), a compressor, a condenser (45), an expansion valve, in which circulates a refrigerant fluid (F1), characterized in the condenser (45) is constituted by a two-stage heat exchanger (10, 12) according to one of the Claims 1 to 7.