AIR BYPASS FLOW

FIELD

[0001] The specification relates to a heat exchanger having an air bypass seal, and a heat exchanger assembly having the heat exchanger and the seal.

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 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 has a seal that 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; a fluid manifold being fluidly coupled to the flow passages of the spaced- apart plate pairs; the heat exchanger having a front face and side faces defined by at least the plurality of spaced-apart plate pairs and the one or more fins; and a bypass seal complementary to the front face or one of the side faces and engagingly coupled to the front face or one of the side faces for blocking a gap between the heat exchanger and a housing for receiving the heat

exchanger.

[0007] In another aspect, disclosed is a heat exchanger assembly containing a housing having a cavity in communication with an opening for receiving a heat exchanger; and the heat exchanger as disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Reference will now be made, by way of example, to the

accompanying drawings which show example embodiments of the present application, and in which :

[0009] Figure 1 shows an air intake manifold for receiving a heat exchanger in accordance with the specification;

[0010] Figure 2(a) shows a heat exchanger having a clip-on bypass seal in accordance with a second embodiment of the specification;

[0011] Figures 2(b) and (c) show an alternative clip-on bypass seal attachable to a heat exchanger in accordance with the second embodiment of the specification ;

[0012] Figure 2(d) shows a sectional view of a heat exchanger with the clip-on bypass seal in accordance with the second embodiment of the

specification in an air intake manifold;

[0013] Figure 2(e) shows a top view of the heat exchanger in an air-intake manifold in accordance with the second embodiment of the specification;

[0014] Figure 3(a) shows a schematic elevational view of a heat exchanger having a clip-on bypass seal in accordance with one embodiment of the specification ; [0015] Figure 3(b) shows a top plan view of the heat exchanger of Figure 3(a);

[0016] Figure 4 shows the clip-on bypass seal in accordance with one embodiment of the specification for use with a heat exchanger;

[0017] Figure 5 is a perspective view of the air intake manifold having a cut-out within the manifold for receiving the bypass seal present on a heat exchanger;

[0018] Figure 6(a) shows a heat exchanger having a clip-on bypass seal in accordance with a third embodiment of the specification;

[0019] Figure 6(b) shows an expanded view of clip-on bypass seal used with the heat exchanger in accordance with the third embodiment of the specification ;

[0020] Figures 7 (a)-(d) shows views of an end section of heat exchanger having a retainer for clipping in place the clip-on bypass seal in accordance with a fourth embodiment of the specification;

[0021] Figures 8 shows a heat exchanger having a brazed-on bypass seal in accordance with a fifth embodiment of the specification;

[0022] Figure 9 shows an expanded view of an end portion of the heat exchanger having the brazed-on seal as shown in Figure 8;

[0023] Figure 10 shows an embodiment of a seal for use with the heat exchanger shown in Figure 8; and

[0024] Figure 11 another view of the seal shown in Figure 10.

[0025] Similar reference numerals may have been used in different figures to denote similar components.

DESCRIPTION

[0026] 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. [0027] 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.

[0028] The heat exchanger (2) used in accordance with the disclosure is not particularly limited. In one example embodiment, as shown in Figure 2a, 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) (more clearly seen Figure 6) having an inlet (16) and outlet (18) 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 Figure 2(a), the inlet and outlet can be present on a top plate (20). While in another embodiment, as shown in Figure 6, the inlet (16) and outlet (18) can be present on a side face (22) of the heat exchanger (2).

[0029] 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.

[0030] 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.

[0031] In addition, the heat exchanger (2) as disclosed herein, are provided with side faces (22). In the embodiment shown in figure 6a, one of the side faces is formed by the fluid manifold ( 14) while the other side face is formed by the ends of the plate pairs (12) along with the ends of the fins (24).

[0032] The heat exchanger (2), as disclosed herein, is also provided with a bypass seal (28) that is complementary to the front face (26) or one of the side faces (22) of the heat exchanger. The complementary bypass seal (28) is coupled to the front face (26) or one of the side faces (22) of the heat

exchanger to block a gap that can be present between the heat exchanger (2) and the inside of a housing, such as the air intake manifold (4). This can help to prevent air bypass along the side faces (22) of the heat exchanger (2) and improve the overall efficiency of heat exchange.

[0033] In the embodiments shown in Figures 2 and 4, two bypass seals (28) are used, with each seal (28) being complementary to the side face (22) of the heat exchanger (2) to which it is attached. The seals (28) are provided with a heat exchanger engaging face (30) and a sealing face (32). It is the heat exchanger engaging face (30) that is complementary in profile to the side face (22) or the front face (26), whichever it engages. In one embodiment, the heat exchanger engaging face (30) is provided with notches (34) (Figures 3 and 4), such that when the seal engages the side face (22) or the front face (26), the grooves formed by the plate pairs (12) and the fins (24) are blocked. While the sealing face (32) helps to block any gaps between the ends of the heat exchanger (2) and the manifold (4).

[0034] The exact shape and dimensions of the seal (28) used in

accordance with the heat exchanger (2) disclosed are not particularly limited. In one embodiment as shown in Figure 2, the sealing face (32) of the bypass seal (28) provides a flat surface. While in another embodiment as shown in Figures 3 and 4, the sealing face (32) is inclined; tapering and becoming narrower as it goes from the top plate (20) towards the bottom of the heat exchanger. For example, in one embodiment, the sealing face (32) is inclined at 1-2°. The angle can help to ensure that the seal (28) does not need to be compressed until the heat exchanger (2) is almost completely inserted in the manifold (4), and hence, assist with installation. [0035] Similarly, the shape and dimension of the heat exchanger engaging face (30) is not particularly limited and would depend upon, among other factors, the particular application and heat exchanger to which the seal (28) is applied to. In the embodiment shown in Figures 3 and 4, the notches (34) present on the heat exchanger engaging face (30) can be deeper, while in other case, the notches (34) can be shallow, depending upon the particular application and heat exchanger used.

[0036] In one embodiment as shown in Figure 5, the manifold (4) is provided with a recess (36) that is complementary to the sealing face (32) of the bypass seal (28) to block the gap between the heat exchanger (2) and the manifold (4). In the embodiment of Figure 5, the recess (36) is tapered, which can assist in both sealing and mounting of the heat exchanger (2) in the manifold (4). In addition, the recess (36) can also assist in retaining the position of the heat exchanger (2) by resisting movement within the manifold. [0037] In further embodiments in accordance with the description, the heat exchanger (2) has a bypass seal (28) positioned on the front face (26) of the heat exchanger (2), as shown, for example in Figures 6-9. In such

embodiments, and as described previously, the seal (28) is also provided with a sealing face (32) and a heat exchanger engaging face (30) that has a profile, which is complementary to the front face (26) of the heat exchanger (2) to which it engages. Further, the seal (28) can be present at an edge (38) of the front face adjacent to the side face (22) of the heat exchanger (2). In the embodiments shown in Figures 6-9, the seal (28) is present at an edge (38), which is adjacent to a side face (22) that has the ends of the plate pairs (12) and the fins (24). However, it would be understood that a second seal (28) can also be provided at the opposing end of the front face (26) of the heat exchanger (2).

[0038] The manifold (4) can be prepared or appropriately manufactured to accommodate a heat exchanger (2) where the seal (28) is present at the front face (26) of the heat exchanger (2). A similar recess (36), as described above, can also be provided to accommodate the seal (28) present on the front face (26).

[0039] The method for attaching the seal (28) to the heat exchanger (2) is not particularly, and can depend upon the particular application, among other factors. In one embodiment, the seal (28) is frictionally attached to the heat exchanger. In another embodiment, the seal (28) is clipped in place and is provided with means for clipping the seal (28) to the heat exchanger (2), as shown in Figure 6. In a further embodiment, the heat exchanger can be provided with tabs (40) for retaining the seal, as shown in Figure 7. The tabs (40) and the seal (28) can be provided with additional means, such as an arm and a gap for insertion of the arm into the gap, to lock the seal (28) in place. Alternatively, the seal (28) can also be bolted on the heat exchanger (2), as shown in Figures 8- 11. In a still further embodiment, the seal (28) can be brazed-on to the heat exchanger (2). Moreover, a combination of methods can be used to position the seal (28) with the heat exchanger (2).

[0040] The material of construction of the seal (28) is not particularly limited and can depend upon the particular application. In one embodiment, for example and without limitation, the seal (28) is made of plastic, such as a thermoplastic. While in another embodiment, the seal (28) can be made of a similar material as the heat exchanger (2) to allow for brazing of the seal (28) to the heat exchanger (2).

[0041] In another aspect in accordance with the description, a heat exchanger assembly is provided, which contains the housing (4) and the heat exchanger (2) as described herein. The entire assembly can be provided and be fitted into an engine for use. Alternatively, the heat exchanger (2) and the manifold (4) can be provided separately.

[0042] Certain adaptations and modifications of the described

embodiments can be made. Therefore, the above discussed embodiments are considered to be illustrative and not restrictive.