1. Field of the Invention
A heat exchanger assembly for transferring heat between a coolant and a stream of air.
2. Description of the Prior Art
U.S. Pat. No. 6,272,881, issued to Kuroyanago et al. on Aug. 14, 2001 (hereinafter referred to as Kuroyanago '881), shows first and second manifolds spaced from one another A cross-over plate is disposed in one of the manifolds for dividing the associated manifold into an upstream section on one side of the cross-over plate and a downstream section on the other side of the cross-over plate. The cross-over plate defines at least one orifice for establishing fluid communication between the upstream and downstream sections of the associated manifold. A core extends between the first and second manifolds for transferring heat between the stream of air and the coolant. The core includes a plurality of tubes defining a plurality of upstream flow paths and a plurality of downstream paths. The upstream flow paths of the tubes are in fluid communication with the upstream section of the one of the manifolds including the cross-over plate, and the downstream flow paths of the tubes are in fluid communication with the downstream section of the one of the manifolds including the cross-over plate. The upstream flow paths define an upstream cross-sectional area, and the downstream flow paths define a downstream cross-sectional area. The orifices of the cross-over plate define a cross-over opening area.
The invention provides for such a heat exchanger assembly and wherein the ratio of the cross-over opening area of the cross-over plate to the upstream cross-sectional area of the upstream flow paths is in the range of XXXXX:XXXXX to XXXXX:XXXXX. This ratio maximizes the efficiency of the heat exchanger assembly by ensuring optimum fluid flow without creating a pressure drop in the coolant flowing through the cross-over plate. A large pressure drop often has the undesirable effect the effect of cooling and/or re-condensing the coolant.
Other advantages of the present invention will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
a is a top view a first embodiment of the cross-over plate according to the subject invention;
b is a plot of the cross-over opening area across the length of the first embodiment of the cross-over plate;
a is a top view a second embodiment of the cross-over plate according to the subject invention;
b is a plot of the cross-over opening area across the length of the second embodiment of the cross-over plate;
a is a top view a third embodiment of the cross-over plate according to the subject invention;
b is a plot of the cross-over opening area across the length of the third embodiment of the cross-over plate;
a is a top view a fourth embodiment of the cross-over plate according to the subject invention; and
b is a plot of the cross-over opening area across the length of the fourth embodiment of the cross-over plate.
Referring to the Figures, wherein like numerals indicate corresponding parts throughout the several views, a heat exchanger assembly 20 for transferring heat between a coolant and a stream of air is generally shown in
The heat exchanger assembly 20 includes a first manifold 22, generally indicated, extending along an axis A between first manifold ends 24. A second manifold 26, generally indicated, extends between second manifold ends 28 in spaced and parallel relationship with the first manifold 22.
A first partition 30 is disposed in the first manifold 22 and extends axially along the first manifold 22 between the first manifold ends 24 to define a first upstream section 32, 34 on one side of the first partition 30 and a first downstream section 36, 38 on the other side of the first partition 30. A second partition 40 is disposed in the second manifold 26 and extends axially along the second manifold 26 between the second manifold ends 28 to define a second upstream section 42 on one side of the second partition 40 and a second downstream section 44 on the other side of the second partition 40. The first upstream section 32, 34 of the first manifold 22 is aligned with the second upstream section 42 of the second manifold 26, and the first downstream section 36, 38 of the first manifold 22 is aligned with the second downstream section 44 of the second manifold 26.
The first manifold 22 includes an inlet 46 disposed on one of the first manifold ends 24 for receiving the coolant. In the exemplary embodiment, the inlet 46 is in fluid communication with the first downstream section 36, 38 of the first manifold 22. The first manifold 22 further includes an outlet 48 spaced from the inlet 46 in a transverse direction for dispensing the coolant. In the exemplary embodiment, the outlet 48 is in fluid communication with the first upstream section 32, 34 of the first manifold 22.
A core 50, generally indicated, is disposed between the first and second manifolds 22, 26 for conveying a coolant therebetween. The core 50 includes a plurality of tubes 52 extending in spaced and parallel relationship to one another between the first and second manifolds 22, 26 for receiving the stream of air in the transverse direction to transfer heat between the stream of air and the coolant in the tubes 52. In the exemplary embodiment, each of the tubes 52 has a cross-section presenting flat sides 54 extending in the transverse direction interconnected by round ends 56 with the flat sides 54 of adjacent tubes 52 spaced from one another by a fin space across the transverse direction.
A plurality of air fins 58 are disposed in the fin space between the flat sides 54 of the adjacent tubes 52 for transferring heat from the tubes 52 to the stream of air.
Each of the tubes 52 includes at least one tube divider 60, best seen in
One of the first and second partitions 30, 40 is further defined as a cross-over plate having at least one orifice 66, 68, 70 for establishing fluid communication between the upstream and downstream sections 42, 44 of the associated one of the first and second manifolds 22, 26. The sum of the cross-sectional areas of the orifices 66, 68, 70 of the cross-over plate defines a cross-over opening area for the flow of coolant between the upstream and downstream sections 34, 38, 42, 44 of the associated one of the first and second manifolds 22, 26. The heat exchanger assembly 20 of
In the four-pass heat exchanger assembly 20 of
In the two-pass heat exchanger assembly 20 of
a shows a first embodiment of the cross-over plate 40 of the two-pass heat exchanger assembly 20. In the first embodiment, the cross-over plate 40 includes a plurality of orifices 66, 68, 70 spaced axially from one another by an orifice space D. The orifices 66, 68, 70 include a first orifice 66 disposed closest to the inlet 46, a plurality of middle orifices 68, and a last orifice 70 disposed farthest from the inlet 46. The orifice space D between adjacent orifices 66, 68, 70 sequentially decreases from the first orifice 66 closest to the inlet 46 to the middle orifices 68 to define the continuously increasing cross-over opening area in the axial direction away from the inlet 46, as shown in
a shows a second embodiment of the cross-over plate 40 of the two-pass heat exchanger assembly 20. In the second embodiment, the cross-over plate 40 includes a plurality of orifices 66, 68, 70 spaced axially from one another by an orifice space D. The orifices 66, 68, 70 include a first orifice 66 disposed closest to the inlet 46, a middle orifice 68, and a last orifice 70 disposed farthest from the inlet 46. The area of the orifices 66, 68, 70 sequentially increases from the first orifice 66 closest to the inlet 46 to the middle orifice 68 to define the continuously increasing cross-over opening area in the axial direction away from the inlet 46, as shown in
a shows a third embodiment of the cross-over plate 40 of the two-pass heat exchanger assembly 20. In the third embodiment, the cross-over plate 40 includes a plurality of orifices 66, 68, 70 disposed in three rows. All of the orifices 66, 68, 70 have the same area, and each row of orifices 66, 68, 70 includes a first orifice 66 disposed closest to the inlet 46, a plurality of middle orifices 68, and a last orifice 70 disposed farthest from the inlet 46. In each row, the orifice space D between adjacent orifices 66, 68, 70 sequentially decreases from a first orifice 66 closest to the inlet 46 to the middle orifices 68 to define the continuously increasing cross-over opening area in the axial direction away from the inlet 46, as shown in
a shows a fourth embodiment of the cross-over plate 40 of the two-pass heat exchanger assembly 20. In the fourth embodiment, the cross-over plate 40 includes a plurality of orifices 66, 68, 70 disposed in two rows. In contrast to the first, second, and third embodiments, where the orifices 66, 68, 70 are all circular in shape, the orifices 66, 68, 70 of the fourth embodiment are oval shaped. It should be appreciated that the orifices 66, 68, 70 can present any shape to transfer the coolant between the upstream and downstream sections 34, 38, 42, 44 of the associated one of the first and second manifolds 22, 26. Each row of orifices 66, 68, 70 includes a first orifice 66 closest to the inlet 46, a plurality of middle orifices 68, and a last orifice 70 farthest from the inlet 46. In each row, the orifice space D between adjacent orifices 66, 68, 70 sequentially decreases from a first orifice 66 closest to the inlet 46 to the middle orifices 68 to define the continuously increasing cross-over opening area in the axial direction away from the inlet 46, as shown in
As can be seen from
The sum of the cross-sectional areas of the upstream flow paths 62 adjacent to the orifices 66, 68, 70 of the cross-over plate is defined as an upstream cross-sectional area, and the sum of the cross-sectional areas of the downstream flow paths 64 adjacent to the orifices 66, 68, 70 of the cross-over plate is defined as a downstream cross-sectional area. In other words, in the four-pass heat exchanger assembly 20 of
The ratio of the cross-over opening area, described above, of the cross-over plate to the downstream cross-sectional area of the tubes 52 is XXXX:XXXX. This maximizes the efficiency of the heat exchanger assembly 20 without creating an undesirable pressure drop in the coolant flowing through the cross-over plate.
While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.