Note: Descriptions are shown in the official language in which they were submitted.
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HEAT EXCHANGER PLATES WITH INTEGRAL BYPASS
BLOCKING TABS
FIELD
[0001] The specification relates to a heat exchanger having an air bypass
blocking tabs, and a heat exchanger assembly having a housing and the heat
exchanger described herein.
BACKGROUND
[0002] Charge air cooler heat exchangers are well known in the art for
mounting along the flow path of charge air supplied to a combustion engine.
This
charge air typically comprises ambient air which has been compressed by
apparatus
such as a supercharger or turbocharger to provide an increased mass flow of
air to
the engine to permit the engine to combust increased quantities of fuel and
thereby
operate at an increased level of power and performance. However, compression
of
ambient air also elevates the air temperature such that the charge air has a
relatively high temperature which, if not reduced, undesirably increases total
engine heat load. It is therefore desirable to cool the charge air prior to
supply
thereof to the engine, and charge air coolers are provided for this purpose.
[0003] In general, the charge air cooler is constructed from a plurality of
lightweight heat transfer elements of a heat conductive material, such as
copper or
aluminum, shaped to provide extended heat transfer surfaces and defining a
flow
path for the charge air in heat transfer relation with a suitable coolant,
such as
ambient air or a liquid coolant. More specifically, the charge air cooler may
be
constructed from a network of finned tubes such that charge air flowing over
the
fins is associated with a coolant flowing through the tubes resulting in
adequate
heat transfer for some engine system applications. Alternatively, when
improved
heat transfer capacity is required, the charge air cooler is constructed from
a
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stacked array of plates and fins which cooperate to define a heat exchanger
core
having separate flow paths for passage of the charge air and the coolant in
close
heat transfer relation with each other. In either case, however, the charge
air
cooler is desirably mounted directly into the intake manifold of the engine
wherein
charge air passing through the intake manifold is reduced in temperature by
flow
through the charge air cooler immediately prior to ingestion by the engine.
[0004] The current heat exchanger products can allow air bypass past
the
ends of the fins (the plate lap joints extend beyond the end of the fins, or
extend
beyond the liquid fluid manifold, leaving unintended air bypass channels), or
require additional brazed on components to compensate by blocking off these
regions, which adds significant cost and/or may be impossible for certain
cooler
configurations. To address the above problem, wide elastomer seals can be
provided, such as adhesively bonded or mechanically trapped seals, as part of
the
ducting installation - to minimize such bypass. But these seal materials are
expensive, add assembly complexity, and have service durability limitations.
Another compensating alternative is to overdesign the heat exchanger, either
by
over-sizing or adding much higher fin density (pressure drop penalty) so that
performance is maintained even with bypass flow, which can have other
disadvantages.
[0005] There is a need in the art for a heat exchanger and a heat exchanger
assembly, where the heat exchanger can reduce or prevent air bypass around the
ends of the heat exchanger.
SUMMARY OF THE INVENTION
[0006] In one aspect, the specification discloses a heat exchanger,
containing:
a plurality of spaced-apart plate pairs, where each plate pair defines a flow
passage for the flow of a first fluid;
one or more fins thermally coupled and sandwiched by the spaced-apart
plate pairs for flow of a second fluid;
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a fluid manifold being fluidly coupled to the spaced-apart plate pairs at a
manifold end of the spaced-apart plate pairs; and
a tab extending from a flange end of a first plate of a first plate pair and
being in contact with a second tab extending from a flange end of a second
plate of
a second plate pair for providing a fluid flow blocker.
[0007] In another aspect, the specification discloses a heat
exchanger
containing
a plurality of spaced-apart plate pairs, where each plate pair defines a flow
passage for the flow of a first fluid;
one or more fins thermally coupled and sandwiched by the spaced-apart
plate pairs for flow of a second fluid;
a fluid manifold being fluidly coupled to the spaced-apart plate pairs at a
manifold end of the spaced-apart plate pairs; and
a tab extending from a flange end of a first plate of the first plate pair and
being in contact with a second plate of a second plate pair for providing a
fluid flow
blocker.
[0008] In a further aspect, the specification discloses a heat
exchanger
assembly containing
a housing having a cavity in communication with an opening; and
a heat exchanger, as described herein, receivable in the cavity of the
housing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Reference will now be made, by way of example, to the
accompanying
drawings which show example embodiments of the present application, and in
which:
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[0010] Figure 1 shows an air intake manifold for receiving a heat
exchanger in
accordance with an embodiment of the specification;
[0011] Figure 2 shows a front elevational view of a heat exchanger in
accordance with a first embodiment of the specification;
[0012] Figure 3 shows a side elevational view of a heat exchanger in
accordance with a first embodiment of the specification;
[0013] Figure 4 shows a perspective view of an expanded portion of
the heat
exchanger in accordance with a first embodiment of the specification;
[0014] Figure 5 shows a perspective view of an expanded portion of a
single
plate of a plate pair in accordance with a first embodiment of the
specification;
[0015] Figure 6 shows a perspective view of an expanded portion of a
single
plate of a plate pair in accordance with a second embodiment of the
specification;
[0016] Figure 7 shows a perspective view of an expanded portion of a
single
plate of a plate pair in accordance with a third embodiment of the
specification; and
[0017] Figure 8 shows a side elevational view of an expanded portion of a
plate pair in accordance with a fourth embodiment of the specification.
[0018] Similar reference numerals may have been used in different
figures to
denote similar components.
DESCRIPTION
[0019] The specification generally relates to heat exchanger (2),
such as a
charge air cooler for reducing the temperature of air inflow to a combustion
engine.
[0020] The heat exchanger (2) is typically placed in an air intake
manifold
(4), as shown in Figure 1, which has a cavity (6) for placing the heat
exchanger (2)
through an opening (8). Incoming air enters the manifold (4) through an air
intake
aperture (10) and passes the heat exchanger (2) before being directed to the
combustion engine.
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[0021] The heat exchanger (2) used in accordance with the disclosure
is not
particularly limited. In one example embodiment, as shown in Figures 2 and 4,
the
heat exchanger (2) has a plurality of spaced-apart plate pairs (12), where
each
plate pair defines a flow passage for the flow of a first fluid, such as a
coolant. A
fluid manifold (14) having an inlet (16) and outlet (18) (Figures 2 and 3) is
also
provided; where the fluid manifold (14) is connected to the flow passage of
each
plate pair (12) to allow fluid, such as the coolant, to enter through the
inlet (16)
pass through the flow passages of the plate pairs (12) and exit through the
outlet
(18). The position of the fluid manifold (14) and the inlet (16) and outlet
(18) are
not particularly limited. In one embodiment, as shown in Figures 2 and 3, the
inlet
and outlet can be present on a top plate (20). While in another embodiment
(not
shown), the inlet (16) and outlet (18) can be present on a side face (22) of
the
heat exchanger (2).
[0022] The space between each spaced-apart plate pair (12) is
provided with
a fin (24). The fins (24) can provide for a second fluid flow passage,
generally the
air entering through the air intake aperture (10); and where the second flow
passage is perpendicular to the flow passage defined by the plate pairs (12)
to
allow for heat exchange.
[0023] The heat exchanger (2) as disclosed herein, has a front face
(26) such
that when the heat exchanger (2) is positioned in the air intake manifold (4),
the
front face (26) is positioned at the air intake aperture (10) and allows for
the
second fluid, the air, to pass through the fins (24) and undergo heat exchange
before entering the combustion engine.
[0024] In addition, each plate of the heat exchanger (2), as
disclosed herein,
has a manifold end (28) and an opposing end (30), denoted herein as the flange
end (30). The manifold end (28) of the heat exchanger plates have the fluid
manifold (14) coupled to the plates, while the flange end (30) have one or
more
tabs (32) for blocking air bypass. The heat exchanger (2), as disclosed
herein, are
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provided with side faces (22). In the embodiment shown in Figure 2, one of the
side faces is formed by the fluid manifold (14) while the other side face is
formed
by the flange ends (30) of the plate pairs (12) along with the ends of the
fins (24)
(Figure 4).
[0025] In the embodiment shown in Figures 2-5, each plate of the heat
exchanger (2) is provided with a tab (32) at the flange end. The tab (32) in
each
plate can be formed by creating a cut at the flange end (30) of the plates and
folding up the cut section of the flange end (30), to create a face of the tab
(34)
(Figures 4 and 5) that is essentially perpendicular to the air flow direction.
[0026] The length of the tabs (32) in accordance with the specification is
not
particularly limited. In the embodiments disclosed in Figures 2-7, the length
of the
tabs (32) in each plate of the heat exchanger (2) can be set such that in the
assembled heat exchanger (2), a tab (32) extending from a flange end (30) of a
first plate of a first plate pair is in contact with a second tab extending
from a
second plate of a second (or adjacent) plate pair, in the heat exchanger (2).
In
another embodiment, as shown in Figure 8, a tab (32) extending from the flange
end (30) of a first plate is in contact with a second plate of an adjacent (or
second)
plate pair. By adjusting the size and position of the tabs (32), air that
bypasses at
the flange end (30) of the heat exchanger (2) can be blocked.
[0027] The number of tabs (32) in accordance with the specification is not
particularly limited. In the embodiments shown in Figures 2-5 and 7, each
plate of
the heat exchanger (2) is provided with a single tab (32). While in the
embodiment shown in Figure 6, each plate of the heat exchanger (2) is provided
with a pair of tabs (32).
[0028] The position of the tabs (32) in each plate of the heat exchanger
(2) is
not particularly limited. In one embodiment in accordance with the
specification, as
shown Figures 2-5, the tab (32) in each plate is centrally positioned at the
flange
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end (30) of the heat exchanger. While in other embodiments in accordance with
the specification, and as shown in Figures 6-8, the tabs (32) in each plate
are
positioned at a corner of the flange end (30). When the tabs (32) are
positioned
near a corner of the flange end (30), in the assembled heat exchanger (2), the
tabs
(32) can be proximate to the front face (26) or back face (36) (i.e., the face
away
from the air intake aperture (10) of the manifold (4)), depending upon the
design
and other requirements.
[0029] In the embodiments shown in the figures, the tabs (32) project
nearly
perpendicularly from the plates of the heat exchanger (2). However, it should
be
understood that the tabs (32) can be at an angle relative to the plane of the
plates
of the heat exchanger (2). Further, in the embodiments as shown in the
figures,
the tabs (32) can be provided with a bent neck (38) that can help with
aligning of
the tabs (32) in adjacent plate pairs. Alternatively, the bent neck (38) can
be used
for contacting a plate of the adjacent plate pair in the heat exchanger (2).
[0030] The method of maintaining contacts between the tabs (32) or tab (32)
and plate in a heat exchanger (2) is not particularly limited in accordance
with
specification. In one embodiment, the tabs (32) can be contact with adjacent
tabs
(32) or plate of a plate pair in the heat exchanger (2). In an alternate
embodiment, the tabs (32) can be brazed to tabs (32) on a plate in an adjacent
plate pair or to a plate in an adjacent plate pair to prevent air bypass.
[0031] In another aspect, the specification discloses a heat
exchanger
assembly containing the housing (4) and the heat exchanger (2), as described
herein. The presence of the tabs (32) in the heat exchanger (2) and the heat
exchanger assembly can help to reduce the air bypass and improve the
efficiency of
the heat exchange.
[0032] Certain adaptations and modifications of the described
embodiments
can be made. Therefore, the above discussed embodiments are considered to be
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illustrative and not restrictive.
