U.S. patent application number 13/253310 was filed with the patent office on 2012-04-05 for heat exchangers for air conditioning systems.
This patent application is currently assigned to Frenger Systems Limited. Invention is credited to Michael AINLEY, Andrew Gaskell.
Application Number | 20120080174 13/253310 |
Document ID | / |
Family ID | 43243536 |
Filed Date | 2012-04-05 |
United States Patent
Application |
20120080174 |
Kind Code |
A1 |
AINLEY; Michael ; et
al. |
April 5, 2012 |
HEAT EXCHANGERS FOR AIR CONDITIONING SYSTEMS
Abstract
In the field of heat exchangers for air conditioning systems
there is a need for an improved heat exchanger which provides
improved efficiency in terms of overall packaging and performance.
A heat exchanger, for use in an air conditioning system of a
building, including an elongate fluid conduit which has first and
second elongate heat exchange fins extending laterally therefrom.
Opposed faces of the first and second fins define an acute angle
therebetween. The fluid conduit defines a discrete conduit body,
the first fin defines a first fin body, and the second fin defines
a second fin body. The conduit body is thermally coupled to at
least one of the first and second fin bodies by a discrete heat
exchange member.
Inventors: |
AINLEY; Michael; (Derby,
GB) ; Gaskell; Andrew; (Derby, GB) |
Assignee: |
Frenger Systems Limited
Derby
GB
|
Family ID: |
43243536 |
Appl. No.: |
13/253310 |
Filed: |
October 5, 2011 |
Current U.S.
Class: |
165/181 |
Current CPC
Class: |
F28F 1/14 20130101; F28F
2215/08 20130101; F24F 13/30 20130101; F28F 13/12 20130101; F28D
1/0477 20130101; F28F 1/20 20130101; F28F 13/06 20130101 |
Class at
Publication: |
165/181 |
International
Class: |
F28F 1/12 20060101
F28F001/12 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 5, 2010 |
GB |
1016750.0 |
Claims
1. A heat exchanger, for use in an air conditioning system of a
building, comprising: an elongate fluid conduit having first and
second elongate heat exchange fins extending laterally therefrom,
opposed faces of the first and second fins defining an acute angle
therebetween, the fluid conduit defining a discrete conduit body,
the first fin defining a first fin body, and the second fin
defining a second fin body, the conduit body being thermally
coupled to at least one of the first and second fin bodies by a
discrete heat exchange member.
2. A heat exchanger according to claim 1 wherein the discrete heat
exchange member extends at least partially around the conduit
body.
3. A heat exchanger according to claim 1 wherein the conduit body
is removably retained between the first and second fin bodies.
4. A heat exchanger according to claim 1 wherein the first and
second fin bodies are integrally formed with one another.
5. A heat exchanger according to claim 1 further comprising a
second pair of first and second elongate heat exchange fins
extending laterally from the fluid conduit.
6. A heat exchanger according to claim 5 wherein the respective
first heat exchange fins are integrally formed with one another to
define a unitary first fin body and the respective second heat
exchange fins are integrally formed with one another to define a
unitary second fin body.
7. A heat exchanger according to claim 1 wherein the first and
second fin bodies are selectively separable from one another.
8. A heat exchanger according to claim 7 wherein the first and
second fin bodies are secured to one another by at least one
selectively removable fastener.
9. A heat exchanger according to claim 1 further comprising a heat
transfer member including an elongate member having a uniform
cross-sectional profile.
10. A heat exchanger according to claim 9 wherein the heat transfer
member defines a receiving formation to receive at least a portion
of the fluid conduit.
11. A heat exchanger according to claim 9 wherein the heat transfer
member cooperates with the first and second fin bodies to removably
retain the conduit body between the first and second fin
bodies.
12. A heat exchanger according to claim 9 wherein the heat transfer
member includes first and second heat transfer member portions.
13. A heat exchanger according to claim 12 wherein each heat
transfer member portion defines a part of the receiving formation
and is separable from the other heat transfer member portion.
14. A heat exchanger according to claim 11 wherein the first and
second heat transfer member portions lie spaced from one
another.
15. A heat exchanger assembly including a plurality of heat
exchangers according to claim 1 arranged side by side one another
in a heat exchange matrix, the fluid conduit of one heat exchanger
being fluidly connected with the fluid conduit of at least one
adjacent heat exchanger.
16. A heat exchanger according to claim 2 wherein the conduit body
is removably retained between the first and second fin bodies.
17. A heat exchanger according to claim 12 wherein the first and
second heat transfer member portions lie spaced from one another.
Description
[0001] This invention relates to a heat exchanger for use in an air
conditioning system of a building, and a heat exchanger assembly
including a plurality of such heat exchangers.
[0002] A conventional heat exchanger 10 typically includes a planar
baffle 12 within which is located a fluid conduit 14 to convey
heating or cooling fluid through the baffle 12. Such heat
exchangers 10 are able to provide both convective and radiant heat
transfer.
[0003] Normally a plurality of such heat exchangers 10 are
integrated into a heat exchanger assembly 16, as shown in FIG.
1.
[0004] One drawback of the conventional heat exchanger 10 is that
when incorporated into a heat exchanger assembly 16 the resulting
packing efficiency is low, and so the conventional heat exchanger
10 offers poor efficiency.
[0005] There is, therefore, a need for an improved heat exchanger
which provides improved efficiency in terms of overall packaging
and performance.
[0006] According to a first aspect of the invention there is
provided a heat exchanger, for use in an air conditioning system of
a building, comprising an elongate fluid conduit having first and
second elongate heat exchange fins extending laterally therefrom,
opposed faces of the first and second fins defining an acute angle
therebetween, the fluid conduit defining a discrete conduit body,
the first fin defining a first fin body and the second fin defining
a second fin body, the conduit body being thermally coupled to at
least one of the first and second fin bodies by a discrete heat
exchange member.
[0007] The inclusion of first and second fins which have opposed
faces that define an acute angle between them means that for a
given effective surface area the heat exchanger has a smaller
maximum dimension than a conventional heat exchanger. As a result,
for a given effective surface area, a heat exchanger assembly
including the heat exchanger of the invention is smaller in at
least one dimension than a conventional heat exchanger assembly
having the same effective surface area.
[0008] Having the fluid conduit define a discrete conduit body, and
the first and second fins define respective fin bodies provides the
option of separating the conduit body from the fin bodies, e.g. if
the conduit body requires repair of maintenance.
[0009] Thermally coupling of the conduit body to at least one fin
body by a heat transfer member allows for an increased surface area
of the fluid conduit to be utilised for heat transfer, thereby
improving the cooling/heating performance of the heat
exchanger.
[0010] Meanwhile the inclusion of a discrete such heat transfer
member provides the option of forming the heat transfer member from
a different material from that of the conduit body and/or the or
each of the first and second fin bodies, e.g. a highly thermally
conductive material, to further improve the performance of the heat
exchanger.
[0011] Optionally the discrete heat exchange member extends at
least partially around the conduit body. Such an arrangement
increases the rate of heat transfer between the conduit body and
the or each heat exchange fin.
[0012] The conduit body may be removably retained between the first
and second fin bodies. Removably retaining the conduit body between
the first and second fin bodies provides the heat exchanger with a
desired degree of structural integrity during normal use but
facilitates ready repair and/or maintenance of one or more of the
conduit body and the fin bodies.
[0013] In a preferred embodiment of the invention the first and
second fin bodies are integrally formed with one another. Such an
arrangement simplifies manufacture of the heat exchanger since it
minimises the number of components that an assembly operative needs
to handle, i.e. the operative needs only to handle a conduit body
and integrally formed first and second fins.
[0014] In a preferred embodiment of the invention the heat
exchanger includes a second pair of first and second elongate heat
exchange fins extending laterally from the fluid conduit. The
inclusion of an additional pair of heat exchange fins further
increases the effective surface area of the heat exchanger.
[0015] Preferably the respective first heat exchange fins are
integrally formed with one another to define a unitary first fin
body and the respective second heat exchange fins are integrally
formed with one another to define a unitary second fin body. Such
an arrangement further assists in the efficient manufacture and
assembly of the heat exchanger.
[0016] In another preferred embodiment of the invention the first
and second fin bodies are selectively separable from one another.
The ability to separate the first and second fin bodies from one
another assists in assembling the heat exchanger of the invention
and/or the selective removal of the fluid conduit for repair or
maintenance.
[0017] Optionally the first and second fin bodies are secured to
one another by at least one selectively removable fastener. The use
of such a fastener ensures a desired degree of structural integrity
while facilitating ready separation, as desired.
[0018] Preferably the heat transfer member is or includes an
elongate member having a uniform cross-sectional profile. Such a
heat transfer member may be readily manufactured, e.g. by
extrusion, and may be slidably coupled with the elongate fluid
conduit.
[0019] The heat transfer member may define a receiving formation to
receive at least a portion of the fluid conduit. Having the heat
transfer member define such a receiving formation helps to ensure
that the heat transfer member abuts directly with a maximum
external surface area of the fluid conduit so as to maximise the
rate of heat transfer between the fluid conduit and the heat
transfer member.
[0020] In a preferred embodiment of the invention the heat transfer
member cooperates with the first and second fin bodies to removably
retain the conduit body between the first and second fin bodies.
Such an arrangement obviates the need for any other fastening or
securing means between the fin bodies and the fluid body while
allowing ready removal of the fluid conduit as may be desired from
time to time.
[0021] Optionally the heat transfer member includes first and
second heat transfer member portions. Such an arrangement assists
in the assembly of the heat exchanger while providing a desired
increase in the rate of thermal transfer between the fluid conduit
and the or each heat exchange fin.
[0022] Each heat transfer member portion may define a part of the
receiving formation and may be separable from the other heat
transfer member portion. The inclusion of separable heat transfer
member portions assists, for example, in the removal of the fluid
conduit for repair and/or maintenance.
[0023] Preferably the first and second heat transfer member
portions lie spaced from one another. Spacing the first and second
heat transfer member portions from one another helps to ensure a
uniform distribution of heat transfer capability between the first
and second heat exchange fins.
[0024] In a still further preferred embodiment of the invention at
least one of the first and second fin bodies includes a retention
element to maintain the heat transfer member in cooperation with
the first and second fin bodies.
[0025] The inclusion of a retention element simplifies assembly of
the heat exchangers and reduces the need for specialist tools in
the assembly process.
[0026] Preferably at least one heat exchange fin includes at least
one fluid deflector to direct fluid from one face of the heat
exchange fin to another, opposite face of the heat exchange fin,
the or each fluid deflector extending lengthwise along the heat
exchange fin. The inclusion of one or more fluid deflectors
improves the convective heating or cooling effect of the heat
exchanger by allowing fluid, e.g. air, to pass through the
corresponding fin.
[0027] In another preferred embodiment of the invention each of the
first and second fins in a respective pair of fins includes at
least one fluid deflector, the fluid deflectors in each pair of
heat exchange fins cooperating to direct fluid between a first
region lying between opposed faces of the first and second fins and
a second region lying outside the opposed faces of the first and
second fins. Such an arrangement allows fluid, e.g. air, to move
between warm and cool regions adjacent to the heat exchanger,
thereby further improving the convective heat transfer effect of
the invention.
[0028] In a still further preferred embodiment of invention the or
each fluid deflector includes a deflector element inclined at an
angle relative to the remainder of the fin body of the
corresponding fin to entrain fluid against a face of the fin.
Entraining fluid against a face of a fin increases the heat
transfer coefficient between the fluid and the fin, and so further
improves the efficiency of the heat exchanger.
[0029] According to a second aspect of the invention there is
provided a heat exchanger assembly including a plurality of heat
exchangers as mentioned hereinabove arranged side by side one
another in a heat exchange matrix, the fluid conduit of one heat
exchanger being fluidly connected with the fluid conduit of at
least one adjacent heat exchanger. Such a heat exchanger assembly
offers a large effective surface area for a given maximum external
dimension, e.g. maximum width or maximum depth, and is highly
efficient.
[0030] There now follows a brief description of preferred
embodiments of the invention, by way of non-limiting examples, with
reference to the accompanying drawings in which:
[0031] FIG. 1 shows a conventional heat exchanger assembly;
[0032] FIG. 2 shows an end elevational view of a heat
exchanger;
[0033] FIG. 3(a) shows an end elevational view of a heat exchanger
according to a first embodiment of the invention;
[0034] FIG. 3(b) shows a perspective view of the heat exchanger
shown in FIG. 3(a);
[0035] FIG. 3(c) shows a perspective view of a modified version of
the heat exchanger shown in FIG. 3(a);
[0036] FIG. 4 shows an end elevational view of a heat exchanger
according to a second embodiment of the invention;
[0037] FIG. 5 shows an end elevational view of a heat exchanger
according to a third embodiment of the invention;
[0038] FIG. 6 shows an end elevational view of another heat
exchanger;
[0039] FIGS. 7(a) to 7(f) show various embodiments of heat exchange
fin;
[0040] FIG. 8 shows a perspective view of a heat exchanger assembly
according to another embodiment of the invention;
[0041] FIG. 9 shows an end elevational view of a heat exchanger
according to a fourth embodiment of the invention; and
[0042] FIG. 10 shows a perspective view of a heat exchanger
assembly including a plurality of the heat exchangers shown in FIG.
9.
[0043] A heat exchanger is designated generally by the reference
numeral 30, as shown in FIG. 2.
[0044] The heat exchanger 30 includes an elongate fluid conduit 32
which has first and second elongate heat exchange fins 34, 36
extending laterally therefrom.
[0045] In the arrangement shown the fluid conduit 32 is a tube, and
in particular a copper tube. Copper tubing is readily available
together with a variety of standard couplings to permit the fluid
connection of one length of tube to another in an easy and reliable
manner.
[0046] A single length of such tubing may also be formed into a
desired serpentine coil before respective first and second heat
exchange fins 34, 36 are fastened thereto. This avoids the need for
couplings to interconnect respective lengths of the tubing, and the
resulting omission of any joints in the fluid conduit minimises the
risk of a leak occurring.
[0047] A first face 38 of the first fin 34 lies opposite a first
face 40 of the second fin 36, and the first faces 38, 40 between
them define an acute angle. Preferably the angle between the
opposed first faces 38, 40 is between 10.degree. and 40.degree.,
and more preferably between 20.degree. and 30.degree..
[0048] In the arrangement shown the fins 34, 36 are made of
aluminium. The fins may also be made of another thermally
conductive material.
[0049] Optionally the fins 34, 36 are coated to increase radiant
heat exchange. The coating could be a paint, a cathodic electro
coating of an epoxy polymer/paint, or an anodised layer.
[0050] The fluid conduit 32 defines a discrete conduit body 42,
i.e. a conduit body 42 that is distinct from each of the first and
second fins 34, 36. In the arrangement shown the conduit body 42 is
formed from separate material to the first and second fins 34,
36.
[0051] In turn the first fin 34 defines a first fin body 44 and the
second fin 36 defines a second fin body 46. The first and second
fin bodies 44, 46 are selectively separable from one another.
[0052] The conduit body 42 is coupled to each of the first and
second fin bodies 44, 46 and, in particular, the conduit body 42 is
removably retained between the first and second fin bodies 44,
46.
[0053] The first and second fin bodies 44, 46 clamp the conduit
body 42 between them and the fin bodies 44, 46 are themselves
secured to one another by two selectively removable fasteners 48.
In the arrangement shown the removable fasteners 48 are clips 50
which extend at least partially around the conduit body 42.
[0054] Each of the first and second fins 34, 36 includes a
plurality of fluid deflectors 52, each of which extends lengthwise
along the corresponding fin 34, 36. In the arrangement shown each
fin 34, 36 includes three discrete rows of fluid detectors 52.
[0055] Other arrangements may, however, include fewer or greater
than three rows of fluid deflectors 52. Moreover, the relative
arrangement of fluid deflectors 52 in adjacent rows may vary,
together with the relative proportions of each deflector 52, as
shown in FIGS. 7(a) to 7(f). The relative arrangement and
proportions of the fluid deflectors 52 may be varied according to
the degree of convective heat transfer required.
[0056] Each fluid deflector 52 includes a deflector element 54
which is inclined at an angle relative to the remainder of the
corresponding fin body 44, 46.
[0057] In use, to cool air in a room of a building, the heat
exchanger 30 is suspended from a ceiling (not shown) with the first
and second fins 34, 36 extending towards the ceiling, i.e. in an
upwards direction.
[0058] A cooling fluid, e.g. cold water, is passed along the fluid
conduit 32. The fluid conduit 32 draws heat from each of the fins
34, 36 and so lowers the temperature of each fin 34, 36.
[0059] Each fin 34, 36 is therefore able to cool the air in the
room via a degree of radiant heat transfer.
[0060] At the same time the heat exchanger 30 carries out
convective heat transfer by inducing warm air 56 from above and
discharging cooled air 58 from below. In particular the fluid
deflectors 52 on respective fins 34, 36 cooperate to direct the
warm air 56 from a first region 60 between the opposed faces 38, 40
of the fins 34, 36 to a second region 62 lying outside the opposed
faces 38, 40.
[0061] The respective deflector elements 54 of each fluid deflector
52 entrain the warm air 56 against a second face 64, 66 of each fin
34, 36 to maximise the cooling effect of the corresponding fin 34,
36.
[0062] If desired the clips 50 may be removed and the first and
second fin bodies 44, 46 separated from one another to permit
removal of the fluid conduit 32 for repair and/or maintenance.
[0063] A heat exchanger according to a first embodiment of the
invention is designated generally by the reference numeral 70, as
shown in FIGS. 3(a) and 3(b).
[0064] The first heat exchanger 70 shares a number of features with
the heat exchanger 30 described hereinabove and these are
designated using the same reference numerals.
[0065] In this regard the first heat exchanger 70 includes an
elongate fluid conduit 32 and first and second fins 34, 36. As with
the heat exchanger 30 the fluid conduit 32 defines a discrete
conduit body 42, and each of the fins 34, 36 defines a
corresponding fin body 44, 46.
[0066] In contrast to the heat exchanger 30, however, the conduit
body 42 is coupled to each of the first and second fin bodies 44,
46 by a heat transfer member 72.
[0067] In the embodiment shown the heat transfer member 72 is an
elongate member which has a uniform cross-sectional profile. As a
result the heat transfer member 72 may be readily extruded, e.g.
from aluminium, although extrusion from other thermally conductive
materials is also possible.
[0068] The heat transfer member 72 defines a receiving formation 74
which, in the embodiment shown, receives and completely encloses
the fluid conduit 32. The heat transfer member 72 is further formed
of first and second heat transfer member portions 76, 78 each of
which defines a portion of the receiving formation 74. The first
and second heat transfer member portions 76, 78 are separable from
one another.
[0069] In the embodiment shown the first and second heat transfer
member portions 76, 78 are identical mirror images of one another
and, as such, define the same amount of the receiving formation 74,
i.e. one half. Such an arrangement simplifies the production of the
heat transfer member 72 since the first and second heat transfer
member portions 76, 78 share the same cross-sectional profile and
so only a single extrusion is required. In other embodiments (not
shown) the cross-sectional profile of the first and second heat
transfer member portions 76, 78 may differ from one another.
[0070] The heat transfer member 72 cooperates with the first and
second fin bodies 44, 46 to removably retain the conduit body 42
between the fin bodies 44, 46. In particular the first and second
heat transfer member portions 76, 78 lie either side of the conduit
body 42 and clamp it between the fin bodies 44, 46.
[0071] Each fin body 44, 46 includes a retention element 80 in the
form of a tab 82 which maintains the corresponding heat transfer
member portion 76, 78 in cooperation with the associated fin body
44, 46.
[0072] Each fin body 44, 46 also includes a mutually cooperable
connection portion 84 which allows mating with the other fin body
44, 46. A removable fastener 48, e.g. in the form of a nut and bolt
(not shown), may be used to removably secure the fin bodies 44, 46
to one another.
[0073] In use the first heat exchanger 70 functions in a similar
manner to the heat exchanger 30.
[0074] However, the inclusion of a heat transfer member 72 in the
second heat exchanger 70 increases the size of heat transfer
cross-section between the fluid conduit 32 and the fins 34, 36 to
improve further the performance of the second heat exchanger
70.
[0075] FIG. 3(b) illustrates the functioning of the fluid
deflectors 52 and associated deflector elements 54 to pass warm air
56 through the fins 34, 36, entrain it against the second face 58,
60 of each fin 34, 36 before discharging cool air 58 from
below.
[0076] A modified version of the first heat exchanger 70 is shown
in FIG. 3(c).
[0077] The modified second heat exchanger 70a includes a fluid
conduit 32 which has a fluid conduit insert 86 lying within the
conduit 32 to induce turbulence in the fluid flowing within the
conduit 32. This can be advantageous if the fluid has a low flow
rate since it helps to prevent the creation of a boundary layer on
the inner surface of the conduit 32 which would otherwise inhibit
the transfer of heat between the fluid and the conduit 32.
[0078] In the embodiment shown the fluid conduit insert 76 defines
a helical spiral 78. In other embodiments of the invention (not
shown) the fluid conduit insert 76 could be an elongate wire coil
having a generally helical configuration or other swirl-inducing
member.
[0079] Moreover, the fluid conduit insert 76 may be located in the
fluid conduit 32 of any of the other heat exchangers described
herein.
[0080] A heat exchanger according to a second embodiment of the
invention is designated generally by reference numeral 90, as shown
in FIG. 4.
[0081] The second heat exchanger is very similar to the first heat
exchanger 70, and like features share the same reference
numerals.
[0082] In the second heat exchanger 90 the fluid conduit 32 has a
smaller diameter relative to the size of the fins 34, 36, and the
heat transfer member has a different overall cross-sectional
shape.
[0083] The second heat exchanger functions in exactly the same
manner as the first heat exchanger 70.
[0084] A heat exchanger according to a third embodiment of the
invention is designated generally by the reference numeral 100.
[0085] The third heat exchanger 100 is similar to each of the first
and second heat exchangers 70, 90.
[0086] However the third heat exchanger 100 differs in that the
first and second fin bodies 44, 46 are integrally formed with one
another to define a unitary fin body 102.
[0087] In addition the heat transfer member 72 defines a receiving
formation 74 which extends only part way around the fluid conduit
32. The remaining external surface of the fluid conduct abuts
directly against the unitary fin body 102.
[0088] Respective retention elements 80, i.e. tabs 82, retain the
heat transfer member 72 in cooperation with the unitary fin body
102 to removably retain the fluid conduit between the heat transfer
member 72 and the unitary fin body 102.
[0089] In use, e.g. to cool a room in a building, a cooling fluid
passing through the fluid conduit 32 draws heat from the unitary
fin body 102 directly and via the heat transfer member 72.
[0090] Each of the heat exchangers 30; 70; 90; 100 described
hereinabove can be used in a different orientation to that shown in
the figures. In particular, each heat exchanger 30; 70; 90; 100 may
be suspended from a ceiling (not shown) with the first and second
fins 34, 36 extending away from the ceiling, i.e. in a downwards
direction.
[0091] Such arrangements increase the degree of convective heat
transfer while reducing the degree of radiant heat transfer, as
compared to the aforementioned "upward" configurations. Such
varying of the relative degree of convective and radiant heat
transfer can be desirable is certain installations.
[0092] FIG. 6 shows a further heat exchanger 110.
[0093] The further heat exchanger 110 is similar to the first heat
exchanger 30 but includes a first pair 112 of first and second heat
exchange fins 34, 36 and a second pair 114 of first and second fins
34, 36 arranged opposite the first pair 112.
[0094] Respective first fins 34 in each pair 112, 114 are
integrally formed with one another to define a first unitary fin
body 116, while respective second fins 36 in each pair 112, 144 are
integrally formed with one another to define a second unitary fin
body 118.
[0095] The first and second unitary fin bodies 116, 118 clamp the
conduit body 42 between them and the unitary fin bodies 116, 118
are themselves secured to one another by two selectively removable
fasteners 48 in the form of clips 50 which extend at least
partially around the conduit body 42.
[0096] The further heat exchanger 110 functions in a similar manner
to the first heat exchanger 30 but has an increased effective
surface area, as provided by the second pair 114 of first and
second fins 34, 36.
[0097] A heat exchanger assembly according to an embodiment of the
invention is designated generally by the reference numeral 130, and
is shown in FIG. 8.
[0098] The heat exchanger assembly 130 includes a plurality of
first heat exchangers 70 arranged side by side one another in a
heat exchange matrix 132. The first heat exchangers 70 may be
removably secured to one another by one or more selectively
removable fasteners (not shown), e.g. nuts and bolts.
[0099] The fluid conduit 32 of one second heat exchanger 70 is
fluidly connected with the fluid conduit 32 of the adjacent second
heat exchanger 70. Standard fluid connectors may be utilised for
this purpose thereby simplifying construction of the heat exchanger
assembly 130.
[0100] In use, the heat exchanger assembly 130 is suspended from a
ceiling (not shown) with the first and second fins 34, 36 of each
first heat exchanger 70 extending towards the ceiling, i.e. in an
upwards direction.
[0101] Warm air is able to pass through and over the first and
second fins 34, 36 of each first heat exchanger 70 to be cooled,
while the fins 34, 36 themselves are able to provide a degree of
radiant cooling.
[0102] The effective surface area of the heat exchanger assembly
130, i.e. the surface area which is able to affect heat transfer,
is double that of a conventional heat exchanger assembly 16 having
the same overall width and depth.
[0103] FIG. 9 shows a heat exchanger 140 according to a fourth
embodiment of the invention.
[0104] The fourth heat exchanger 140 is similar to the further heat
exchanger 110 in that it includes a first pair 112 of first and
second heat exchange fins 34, 36 and a second pair 114 of first and
second fins 34, 36 arranged opposite the first pair 112.
[0105] The first fins 34 in each pair 112, 114 are integrally
formed with one another to define a first unitary fin body 116,
while respective second fins 36 in each pair 112, 144 are
integrally formed with one another to define a second unitary fin
body 118.
[0106] The first and second unitary fin bodies 116, 118 are
selectively separable from one another.
[0107] The fourth heat exchanger 140 differs from the further heat
exchanger 110 in that the first and second unitary fin bodies 116,
118 have a heat transfer member 72 lying between them and the fluid
conduit 32. In particular, the first unitary fin body 116 has a
first heat transfer member portion 76 lying between it and the
fluid conduit 32 and the second unitary fin body 118 has a second
heat transfer member portion 78 lying between it and the fluid
conduit 32.
[0108] Each of the first and second heat transfer member portions
76, 78 is a planar elongate member which has a uniform
cross-sectional profile. The respective cross-sectional profiles
are identical to one another and each defines a receiving formation
to receive the corresponding heat transfer member portion 76, 78
and a portion of the fluid conduit 32. More particularly, each heat
transfer member portion 76, 78 includes an elongate recess 142 to
receive a portion of the fluid conduit 32.
[0109] Each of the first and second heat transfer member portions
76, 78 extends beyond the fluid conduit 32 in abutting engagement
with the corresponding unitary fin body 116, 118 to increase the
effective area available for heat transfer between the said heat
transfer member portion 76, 78 and the corresponding fin body 116,
118.
[0110] The first and second heat transfer member portions 76, 78
are spaced from one another to help ensure a uniform distribution
of transferred heat between the first and second unitary fin bodies
116, 118.
[0111] Each of the first and second heat transfer member portions
76, 78 cooperates with the corresponding unitary fin body 116, 118
to removably retain the conduit body 32 therebetween. In
particular, each fin body 116, 118 includes a receiving portion
which has a complimentary cross-sectional shape to the
corresponding heat transfer member portion 76, 78.
[0112] A secondary fastener (not shown) such as a clip or a nut and
bolt is used to selectively secure the first and second unitary fin
bodies 116, 118 to one another to affect the aforementioned
retention of the conduit body 32.
[0113] Each of the first and second fins 34, 36 includes a
plurality of fluid deflectors 52, each of which extends lengthwise
along the corresponding fin 34, 36. In the embodiment shown each
fin 34, 36 includes five discrete rows of fluid detectors 52.
[0114] Each fluid deflector 52 includes a deflector element 54
which extends at an angle relative to the remainder of the
corresponding fin body 44, 46. In the embodiment shown each
deflector element 54 has a curved shape although this may vary in
other embodiments of the invention.
[0115] More particularly, the deflector elements 54 in the first
pair 112 of first and second heat exchange fins 34, 36 extend
downwards in use, while the deflector elements 54 in the second
pair 114 of first and second heat exchange fins 34, 36 extend
upwards in use.
[0116] In use the fourth heat exchanger 140 is suspended from a
ceiling (not shown) with the first pair 112 of first and second
fins 34, 36 extending towards the ceiling, i.e. in an upwards
direction.
[0117] A cooling fluid, e.g. cold water, is passed along the fluid
conduit 32. The fluid conduit 32 draws heat from each of the fins
34, 36 and so lowers the temperature of each fin 34, 36.
[0118] Each fin 34, 36 is therefore able to cool the air in the
room via a degree of radiant heat transfer.
[0119] At the same time the heat exchanger 140 carries out
convective heat transfer by inducing warm air 56 from above and
discharging cooled air 58 from below. In particular the fluid
deflectors 52 on the first pair 112 of heat exchange fins 34, 36
allow warm air entrained along and cooled by an upper inner surface
of each fin 34, 36 to pass through the respective fin 34, 36. The
upwardly facing fluid deflectors 52 in the second pair 114 of heat
exchange fins 34, 36 capture the cooled air from the first pair 112
of heat exchange fins 34, 36 and further cool it by entraining it
against a lower inner surface of each fin 34, 36 in the second pair
114.
[0120] A heat exchanger assembly according to a second embodiment
of the invention is designated generally by the reference numeral
150, and is shown in FIG. 10.
[0121] The second heat exchanger assembly 150 includes a plurality
of fourth heat exchangers 140 arranged side by side one another in
a heat exchange matrix 132. The fourth heat exchangers 140 may be
removably secured to one another by one or more selectively
removable fasteners (not shown), e.g. nuts and bolts.
[0122] The fluid conduit 32 of one fourth heat exchanger 140 is
integrally formed with the fluid conduit 32 of the adjacent fourth
heat exchanger 140. This may be achieved by forming a single fluid
conduit 32 into a required serpentine path before respective first
and second fluid bodies 116, 118 are coupled therewith. Standard
fluid connectors could also be utilised to interconnect respective
lengths of fluid conduit 32.
[0123] In use, the second heat exchanger assembly 150 is suspended
from a ceiling (not shown) with the first pair 112 of first and
second fins 34, 36 of each fourth heat exchanger 140 extending
towards the ceiling, i.e. in an upwards direction.
[0124] Warm air is able to pass through and over the first and
second pairs 112, 114 of first and second fins 34, 36 in each
fourth heat exchanger 140 to be cooled, while the fins 34, 36
themselves are able to provide a degree of radiant cooling.
[0125] The effective surface area of the heat exchanger assembly
130, i.e. the surface area which is able to affect heat transfer,
is double that of a conventional heat exchanger assembly 16 having
the same overall width and depth. Meanwhile, having each fluid
conduit 32 lie towards the middle of each fin body 116, 118 helps
to ensure rapid heat transfer between all regions of each fin body
116, 118.
* * * * *