U.S. patent application number 15/745585 was filed with the patent office on 2018-10-18 for fin heat exchanger comprising improved louvres.
This patent application is currently assigned to Valeo Systemes Thermiques. The applicant listed for this patent is Valeo Systemes Thermiques. Invention is credited to Patrick Boisselle, Samuel Bry, Erwan Etienne, Nicolas Francois, Christophe Lenormand.
Application Number | 20180299209 15/745585 |
Document ID | / |
Family ID | 54199870 |
Filed Date | 2018-10-18 |
United States Patent
Application |
20180299209 |
Kind Code |
A1 |
Etienne; Erwan ; et
al. |
October 18, 2018 |
FIN HEAT EXCHANGER COMPRISING IMPROVED LOUVRES
Abstract
The invention relates to a heat exchanger comprising: at least
one fin (4); at least one row of tubes (2), the tubes being
connected to the fin (4) by clamping the tubes (2) in a collar (6)
formed in the fin (4); and at least one row (10) of louvers (12),
said row (10) being formed in the fin (4) and interposed between
two tubes (2) in the row of tubes, each louver (12) comprising a
blade (14) provided with a free edge (16) and a connecting edge
(18) connecting the louver (12) to the fin (4). The connecting edge
(18) of the blade (14) of at least the first louver (12) in the row
(10) forms an upstream edge with respect to the air flow, the free
edge (16) of the blade (14) forming the downstream edge.
Inventors: |
Etienne; Erwan; (Le Mesnil
Saint Denis, FR) ; Boisselle; Patrick; (Le Mesnil
Saint Denis, FR) ; Bry; Samuel; (Le Mesnil Saint
Denis, FR) ; Francois; Nicolas; (Le Mesnil Saint
Denis, FR) ; Lenormand; Christophe; (Le Mesnil Saint
Denis, FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Valeo Systemes Thermiques |
Le Mesnil Saint Denis |
|
FR |
|
|
Assignee: |
Valeo Systemes Thermiques
Le Mesnil Saint Denis
FR
|
Family ID: |
54199870 |
Appl. No.: |
15/745585 |
Filed: |
July 6, 2016 |
PCT Filed: |
July 6, 2016 |
PCT NO: |
PCT/EP2016/065922 |
371 Date: |
June 27, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F28F 1/325 20130101 |
International
Class: |
F28F 1/32 20060101
F28F001/32 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 17, 2015 |
FR |
1556759 |
Claims
1. A heat exchanger comprising: at least one row of tubes; at least
one fin disposed transversely to said row of tubes, the tubes being
connected to the fin by clamping the tubes in a collar formed in
the fin; and at least one row of louvers, said row being formed in
the fin and interposed between two tubes in the row of tubes, each
louver comprising a blade provided with a free edge and a
connecting edge connecting the louver to the fin, wherein the
connecting edge of the blade of at least the first louver in the
row forms an upstream edge with respect to the air flow, the free
edge of the blade forming the downstream edge.
2. The heat exchanger as claimed in claim 1, wherein the heat
exchanger has only one row of tubes, and wherein the connecting
edges of all the blades in the row form an upstream edge with
respect to the air flow, the free edge of the blades forming the
downstream edge.
3. The heat exchanger as claimed in claim 1, wherein the free edge
of at least the last blade in the row forms an upstream edge with
respect to the air flow, the connecting edge of this last blade
forming the downstream edge.
4. The heat exchanger as claimed in claim 3, wherein the row of
louvers comprises two groups of louvers, the louvers of the second
group following the louvers of the first group in the row of
louvers, the connecting edge of the blades of the first group
forming the upstream edge with respect to the air flow, the free
edge of the blades of the first group forming the downstream edge,
and the free edge of the blades of the second group forming the
upstream edge with respect to the air flow, the connecting edge of
the blades of the second group forming the downstream edge.
5. The heat exchanger as claimed in claim 4, wherein the two groups
of louvers comprise equal numbers of louvers.
6. The heat exchanger as claimed in claim 4, wherein the free edge
of the blade of the last louver of the first group is connected to
the free edge of the blade of the first louver of the second group
by a joining blade that forms a bridge substantially parallel to
the surface of the fin.
7. The heat exchanger as claimed in claim 6, wherein the dimension
of the joining blade between the free edge of the blade of the last
louver of the first group and the free edge of the blade of the
first louver of the second group is less than 3 mm.
Description
[0001] The present invention relates to a heat exchanger, and more
particularly to the tubes for a mechanical heat exchanger.
[0002] A heat exchanger generally comprises tubes, through which a
heat transfer fluid is intended to flow, and heat exchange elements
connected to these tubes.
[0003] A distinction is usually made between brazed heat exchangers
and mechanical heat exchangers depending on the method for
manufacturing them.
[0004] In a mechanical heat exchanger, the heat exchange elements,
referred to as "fins" in this case, are connected to the tubes in
the following way. First of all, through-holes for the tubes to
pass through are made in the fins. These through-holes are
generally each delimited by a raised edge forming a neck. Next, the
fins are disposed substantially parallel to one another and each
tube is inserted into a series of aligned holes in the fins.
Finally, a radial expansion of the tubes is brought about by
passing an expansion tool through the inside of these tubes so as
to mechanically join the tubes and the fins by crimping, the necks
delimiting the through-holes for the tubes then forming collars
clamped around the tubes.
[0005] Such heat exchangers are passed through by an air flow, the
fins extending across the flow.
[0006] In order to increase the heat exchange between the fins and
the air flow, deflectors formed of rows of louvers are usually
provided on the fins, the rows being interposed between the tubes
in one and the same row of tubes. Generally, each louver comprises
a blade provided with a free edge and a connecting edge that
connects the louver to the fin.
[0007] In the prior art, the louvers are arranged in two successive
groups of louvers in the row. For the louvers of the first group,
to which the first louver of the row belongs, the free edge of the
blades forms an upstream edge with respect to the air flow, the
connecting edge forming the downstream edge. By contrast, for the
louvers of the second group, to which the last louver of the row
belongs, the connecting edge of the blades of the louvers forms an
upstream edge with respect to the air flow, the free edge forming
the downstream edge.
[0008] It has been found that this configuration has the effect of
creating ineffective regions upon contact with louvers, in which
the flow of air is braked, and so the heat exchange between the fin
and the air flow is reduced.
[0009] The aim of the invention is to improve the performance of
the heat exchanger by choosing a configuration of the louvers which
makes it possible to limit the occurrence of these ineffective
regions.
[0010] To this end, the subject of the invention is a heat
exchanger comprising: [0011] at least one row of tubes, [0012] at
least one fin disposed transversely to said row of tubes; the tubes
being connected to the fin by clamping the tubes in a collar formed
in the fin; and [0013] at least one row of louvers, said row being
formed in the fin and interposed between two tubes in the row of
tubes, each louver comprising a blade provided with a free edge and
a connecting edge connecting the louver to the fin,
[0014] characterized in that the connecting edge of the blade of at
least the first louver in the row forms an upstream edge with
respect to the air flow, the free edge of the blade forming the
downstream edge.
[0015] It has been found, surprisingly, that the configuration in
which the connecting edge of the blade of at least the first louver
forms an upstream edge with respect to the air flow passing through
the fin and its free edge forms the downstream edge makes the air
flow passing through the louvers less turbulent. This has the
effect of limiting the occurrence of ineffective regions, and thus
of increasing the heat exchange between the louvers and the air
flow.
[0016] In this regard, tests have revealed an increase in the heat
exchange of 3% for an equivalent pressure drop compared with the
configurations of the prior art.
[0017] According to a first embodiment of the invention, the heat
exchange has only one row of tubes, and the connecting edges of all
the blades in the row form an upstream edge with respect to the air
flow, the free edge of the blades forming the downstream edge.
[0018] According to a second embodiment of the invention, the free
edge of at least the blade in the row forms an upstream edge with
respect to the air flow, the connecting edge of this blade forming
the downstream edge.
[0019] According to one particular embodiment of the invention, the
row of louvers comprises two groups of louvers, the louvers of the
second group following the louvers of the first group in the row of
louvers, the connecting edge of the blades of the first group
forming the upstream edge with respect to the air flow, the free
edge of the blades of the first group forming the downstream edge,
and the free edge of the blades of the second group forming the
upstream edge with respect to the air flow, the connecting edge of
the blades of the second group forming the downstream edge.
[0020] According to one particular embodiment of the invention, the
two groups of louvers comprise equal numbers of louvers.
[0021] According to one particular embodiment of the invention, the
free edge of the blade of the last louver of the first group is
connected to the free edge of the blade of the first louver of the
second group by a joining blade that forms a bridge substantially
parallel to the surface of the fin.
[0022] According to one particular embodiment of the invention, the
dimension of the joining blade between the free edge of the blade
of the last louver of the first group and the free edge of the
blade of the first louver of the second group is less than 3
mm.
[0023] The invention will be understood better from reading the
following description, which is given solely by way of example and
with reference to the drawings, in which:
[0024] FIG. 1 is a perspective view of a fin of a heat exchanger
according to a first embodiment of the invention;
[0025] FIG. 2 is a perspective view of a fin of a heat exchanger
according to a second embodiment of the invention;
[0026] FIG. 3 is a perspective view of a heat exchanger according
to the invention.
[0027] FIG. 3 shows a mechanical heat exchanger 1 intended to equip
a motor vehicle.
[0028] The heat exchanger comprises a row of tubes 2 (shown in a
truncated manner for reasons of clarity in FIGS. 1 and 2), through
which a conventional heat transfer fluid is intended to flow, and
fins 4 (only one of which is shown for reasons of clarity)
connected to these tubes 2.
[0029] The tubes 2 are connected to the fins 4 by clamping the
tubes in collars 6 formed in the fins 4. To this end, the fins 4
are provided with through-holes 8 for the tubes to pass through.
These through-holes 8 have an oblong overall shape.
[0030] In the example described, the tubes 2 each have an elongate
overall shape and have a substantially oblong cross section. The
tubes 2 are arranged substantially parallel to one another, so as
to form a single row.
[0031] The fins 4 have a substantially flat rectangular overall
shape and are arranged in the heat exchanger 1 in a manner
substantially parallel to one another and perpendicular to the
longitudinal directions of the tubes 2.
[0032] The fins 4 are intended to extend across an air flow from
upstream to downstream, itself passing through the heat exchanger.
Arrows F indicate the direction of travel of the flow.
[0033] In order to increase the heat exchange between the flow F
and the fins 4, the heat exchanger 1 also comprises rows 10 of
louvers 12, which are formed in each fin 4 and are each interposed
between two tubes 2.
[0034] Each louver 12 comprises a blade 14 comprising a free edge
16 and a connecting edge 18 that connects the louver 12 to the fin
4.
[0035] In the two embodiments according to the invention, which are
shown in FIGS. 1 and 2, the connecting edge 18 of the blade 14 of
at least the first louver 12 in the row 10 forms an upstream edge
with respect to the flow F, the free edge 16 of the blade 14
forming the downstream edge.
[0036] More particularly, in the first embodiment, shown in FIG. 1,
the connecting edges 18 of all the blades 14 in the row 10 form an
upstream edge with respect to the air flow F, the free edge 16 of
the blades 14 forming the downstream edge.
[0037] In the second embodiment according to the invention, shown
in FIG. 2, the free edge 16 of at least the last blade 14 in the
row 10 forms an upstream edge with respect to the air flow F, the
connecting edge 18 thereof forming the downstream edge.
[0038] More particularly, in this second embodiment, the row 10
comprises two groups of louvers 12, preferably comprising equal
numbers of louvers 12, the louvers 12 of the second group following
the louvers of the first group in the row 10 of louvers.
[0039] In the example shown in FIG. 2, the row 10 is formed of
fourteen louvers 12 that are distributed in two groups of seven
louvers 12, disposed on either side of a joining blade 20 that
connects the free edge 16 of the last blade 14 of the first group
to the free edge 16 of the first blade 14 of the second group.
[0040] For all the louvers 12 of the first group, the connecting
edge 18 of each blade 14 forms an upstream edge with respect to the
air flow F and the free edge 16 forms the downstream edge.
[0041] By contrast, for the louvers 12 of the second group, the
free edge 16 of each blade 14 forms the upstream edge with respect
to the air flow F, and the connecting edge 18 forms the downstream
edge.
[0042] The joining blade 20 forms a bridge substantially parallel
to the surface of the fin 4 between the two groups of the row 10.
Substantially parallel is understood as meaning that the bridge is
situated in a plane offset with respect to the surface of the fin.
Preferably, the dimension of the joining blade 22 between the free
edge 16 of the blade 14 of the last louver 12 of the first group
and the free edge 16 of the blade 14 of the first louver 12 of the
second group is less than 3 mm.
[0043] The invention is not limited to the embodiments presented,
and further embodiments will be clearly apparent to a person
skilled in the art.
[0044] In particular, a combination of the different embodiments
can be envisioned in order to obtain the desired effects.
* * * * *