The presently disclosed subject matter generally relates to improved heat exchanger devices and systems, and more specifically, to heat exchanger devices and systems incorporating configurations and mechanisms to improve air distribution along the heat exchanger tubes.
Heat exchangers are used in heating, ventilation, air conditioning, and refrigeration (HVAC&R) systems. Heat exchangers generally include tubes for flowing refrigerant through the heat exchanger. Each tube may contain several individual flow channels, or paths. Fins may be positioned between the tubes to facilitate heat transfer between refrigerant contained within the flow paths and an external fluid passing over the tubes. Moreover, heat exchangers may be used in small tonnage systems, such as residential systems, or in large tonnage systems, such as industrial chiller systems.
In order to provide the maximum possible surface area for heat exchange, heat exchangers and fan coils are often made up of two or more generally planar heat exchanger subassemblies, commonly referred to as slabs, which generally have their planes oriented obliquely with respect to the direction of air flow and which, together, occupy the height and width of the duct within which they are located.
Accordingly, there is a need for improved heat exchanger devices and systems incorporating configurations and mechanisms to improve air distribution along the heat exchanger tubes.
Examples of the present disclosure include improved heat exchanger devices and systems. The system can include a first slab of refrigerant tubes and a second slab of refrigerant tubes. The first slab can have (i) an upstream side, (ii) a downstream side, (iii) a linear shaped region, and (iv) a curved region. The second slab can have (i) an upstream side, (ii) a downstream side, (iii) a linear shaped region, and (iv) a curved region. The linear region of the first slab can be closer to the upstream side of the first slab and the curved region of the first slab can be closer to the downstream side of the first slab. Further, the linear shaped region of the second slab can be closer to the upstream side of the second slab and the curved region of the second slab can be closer to the downstream side of the second slab. The downstream side of first slab can be set apart a first distance from the downstream side of the second slab and the upstream side of the first slab can be set apart a second distance from the upstream side of the second slab. Additionally, the second distance can be greater than the first distance.
Further, the heat exchanger system can include a third slab of refrigerant tubes, the third slab having (i) an upstream side, (ii) a downstream side, (iii) a linear shaped region, and (iv) a curved region. The linear shaped region of the third slab can be closer to the upstream side of the third slab and the curved region of the third slab can be closer to the downstream side of the third slab. Further, the downstream side of third slab can be set apart a third distance from the downstream side of one of the first or second slabs and the upstream side of the third slab can be set apart a fourth distance from the upstream side of the slab of the first or second slabs. The third distance can be greater than the fourth distance.
A further example of the present disclosure can provide a heat exchanger system where the first slab of refrigerant tubes can be subdivided into a first group of tubes closer to the upstream side of the first slab and a second group of tubes closer to the downstream side of the first slab. The second slab of refrigerant tubes can be subdivided into a third group of tubes closer to the upstream side of the second slab and a fourth group of tubes close to the downstream side of the second slab. The third slab of refrigerant tubes can be subdivided into a fifth group of tubes closer to the upstream side of the third slab and a sixth group of tubes close to the downstream side of the third slab.
An additional example of the present disclosure can provide a heat exchanger system where the number of tubes in the first group of tubes can be greater than the number of tubes in the second group of tubes, the number of tubes in the third group of tubes can be greater than the number of tubes in the fourth group of tubes, and the number of tubes in the fifth group of tubes can be greater than the number of tubes in the sixth group of tubes.
A further example of the present disclosure can provide a heat exchanger system where the diameter of each tube in the first group of tubes can be greater than diameter of each tube in the second group of tubes, the diameter of each tube in the third group of tubes can be greater than diameter of each tube in the fourth group of tubes, and the diameter of each tube in the fifth group of tubes can be greater than the diameter of each tube in the sixth group of tubes.
These and other aspects, objects, features, and embodiments will be apparent from the following description and the appended claims.
Reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and which are incorporated into and constitute a portion of this disclosure, illustrate various implementations and aspects of the disclosed technology and, together with the description, serve to explain the principles of the disclosed technology. In the drawings:
It is noted that the drawings of the disclosure are not to scale. The drawings are intended to depict only typical aspects of the disclosure, and therefore should not be considered as limiting the scope of the disclosure. In the drawings, like numbering represents like elements between the drawings.
Disclosed are improved heat exchanger devices and systems incorporating configurations and mechanisms to improve air distribution along the heat exchanger tubes.
Some example implementations of the disclosed technology will be described more fully with reference to the accompanying drawings. This disclosed technology may, however, be embodied in many different forms and should not be construed as limited to the implementations set forth herein. The components described hereinafter as making up various elements of the disclosed technology are intended to be illustrative and not restrictive. Many suitable components that would perform the same or similar functions as components described herein are intended to be embraced within the scope of the disclosed electronic devices and methods. Such other components not described herein may include, but are not limited to, for example, components developed after development of the disclosed technology.
Herein, the use of terms such as “having,” “has,” “including,” or “includes” are open-ended and are intended to have the same meaning as terms such as “comprising” or “comprises” and not preclude the presence of other structure, material, or acts. Similarly, though the use of terms such as “can” or “may” are intended to be open-ended and to reflect that structure, material, or acts are not necessary, the failure to use such terms is not intended to reflect that structure, material, or acts are essential. To the extent that structure, material, or acts are presently considered to be essential, they are identified as such.
By “comprising” or “containing” or “including” is meant that at least the named compound, element, particle, or method step is present in the composition or article or method, but does not exclude the presence of other compounds, materials, particles, method steps, even if the other such compounds, material, particles, method steps have the same function as what is named.
It is also to be understood that the mention of one or more method steps does not preclude the presence of additional method steps or intervening method steps between those steps expressly identified.
The components described hereinafter as making up various elements of the disclosure are intended to be illustrative and not restrictive. Many suitable components that would perform the same or similar functions as the components described herein are intended to be embraced within the scope of the disclosure. Such other components not described herein can include, but are not limited to, for example, similar components that are developed after development of the presently disclosed subject matter.
Reference will now be made in detail to example embodiments of the disclosed technology, examples of which are illustrated in the accompanying drawings and disclosed herein. Throughout this disclosure, reference is made to the downstream and upstream directions. Unless otherwise indicated, the upstream direction is depicted in the drawings as generally downward, and the downstream direction is depicted in the drawings as generally upward.
As further shown, the linear region of the first slab 402 can be closer to the upstream side of the first slab 402, and the curved region of the first slab 402 can be closer to the downstream side of the first slab 403. Additionally, the linear region of the second slab 404 can be closer to the upstream side of the second slab 404, and the curved region of the second slab 404 can be closer to the downstream side of the second slab 404. Further, the linear region of the third slab 406 can be closer to the upstream side of the third slab 406, and the curved region of the third slab 406 can be closer to the downstream side of the third slab 406. The downstream side of first slab 402 can be set apart a first distance from the downstream side of the second slab 404, and the upstream side of the first slab 402 can be set apart a second distance from the upstream side of the second slab 404. As further depicted, the downstream side of third slab 406 can be set apart a third distance from the downstream side of one of the first or second slabs 402, 404, and the upstream side of the third slab 406 can be set apart a fourth distance from the upstream side of the slab of the first or second slabs 402, 404. Such a geometric alignment results in an “N” shape having an enlarged region between slabs due to the presence of the curves. As will be appreciated, such a design increases the flow area and helps prevent the development of a high velocity region.
As further shown, the downstream side of first slab 401 can be set apart a first distance from the downstream side of the second slab 405. The upstream side of the first slab 401 can be set apart a second distance from the upstream side of the second slab 405. The second distance can be greater than the first distance such that the first and second slabs 401, 405 angle inwardly in the direction of flow. The upstream side of the first slab 401 can be attached to the first side of the third slab 403, and the upstream side of the second slab 405 can be attached to the second side of the third slab 403. Such a geometric alignment results in an “A” shape having an enlarged region between slabs due to the presence of the curves. As will be appreciated, such a design increases the flow area and prevents the development of a high velocity region. Further, the trapezoid shape with a tilted surface of the slabs 401, 403, 405 can allow condensate drain down along the slabs 401, 403, 405.
As further depicted, the first region 512 can be closer to the upstream side of the first slab 510 and the second region 514 can be closer to the downstream side of the first slab 510. The number of HX tubes in the first plurality of HX tubes 513a, 513b, 513c can be less than the number of HX tubes in the second plurality of HX tubes 515a, 515b, 515c. Further, the first region 522 can be closer to the upstream side of the first slab 520 and the second region 524 can be closer to the downstream side of the first slab 520. The number of HX tubes in the first plurality of HX tubes 523a, 523b, 523c can be less than the number of HX tubes in the second plurality of HX tubes 525a, 525b, 525c. Further, the first region 532 can be closer to the upstream side of the first slab 530, and the second region 534 can be closer to the downstream side of the first slab 530. The number of HX tubes in the first plurality of HX tubes 533a, 533b, 533c can be less than the number of HX tubes in the second plurality of HX tubes 535a, 535b, 535c. As will be appreciated, having fewer tubes in the region of the slabs 510, 520, 530 with lower airflow will reduce the resistance in the lower airflow region therefore improving the airflow distribution of the heat exchanger system 500. As will be further appreciated, both the number and orientation of the HX tubes can be varied based on the airflow of the system 500.
As further depicted, the first region 512 can be closer to the upstream side of the first slab 510, and the second region 514 can be closer to the downstream side of the first slab 510. The number of HX tubes in the first plurality of HX tubes 513a, 513b, 513c can be less than the number of HX tubes in the second plurality of HX tubes 515a, 515b, 515c. Further, the first region 522 can be closer to the upstream side of the first slab 520, and the second region 524 can be closer to the downstream side of the first slab 520. The number of HX tubes in the first plurality of HX tubes 523a, 523b, 523c can be less than the number of HX tubes in the second plurality of HX tubes 525a, 525b, 525c. As will be appreciated, having fewer tubes in the region of the slabs 510, 520 with lower airflow will reduce the resistance in the lower airflow region therefore improving the airflow distribution of the heat exchanger system 500. As will be further appreciated, both the number and orientation of the HX tubes can be varied based on the airflow of the system 500.
As further depicted, the first region 512 can be closer to the upstream side of the first slab 510, the third region 516 can be closer to the downstream side of the first slab 510, and the second region 514 can be between the first region 512 and the third region 516. The number of HX tubes in the first plurality of HX tubes 513a, 513b, 513c can be less than the number of HX tubes in the second plurality of HX tubes 515a, 515b, 515c. Additionally, the number of HX tubes in the second plurality of HX tubes 515a, 515b, 515c can be less than the number of HX tubes in the third plurality of HX tubes 517a, 517b, 517c. Further, the first region 522 can be closer to the upstream side of the first slab 520, the third region 526 can be closer to the downstream side of the first slab 520, and the second region 524 can be between the first region 522 and the third region 526. The number of HX tubes in the first plurality of HX tubes 523a, 523b, 523c can be less than the number of HX tubes in the second plurality of HX tubes 525a, 525b, 525c. Additionally, the number of HX tubes in the second plurality of HX tubes 525a, 525b, 525c can be less than the number of HX tubes in the third plurality of HX tubes 527a, 527b, 527c. Further, the first region 532 can be closer to the upstream side of the first slab 530, the third region 536 can be closer to the downstream side of the first slab 530, and the second region 534 can be between the first region 532 and the third region 536. The number of HX tubes in the first plurality of HX tubes 533a, 533b, 533c can be less than the number of HX tubes in the second plurality of HX tubes 535a, 535b, 535c. Additionally, the number of HX tubes in the second plurality of HX tubes 535a, 535b, 535c can be less than the number of HX tubes in the third plurality of HX tubes 537a, 537b, 537c. As will be appreciated, having fewer tubes in the regions of the slabs 510, 520, 530 with lower airflow will reduce the resistance in the lower airflow region therefore improving the airflow distribution of the heat exchanger system 500. As will be further appreciated, both the number and orientation of the HX tubes can be varied based on the airflow of the system 500.
As further depicted, the first region 512 can be closer to the upstream side of the first slab 510, the third region 516 can be closer to the downstream side of the first slab 510, and the second region 514 can be between the first region 512 and the third region 516. The number of HX tubes in the first plurality of HX tubes 513a, 513b, 513c can be less than the number of HX tubes in the second plurality of HX tubes 515a, 515b, 515c. Additionally, the number of HX tubes in the second plurality of HX tubes 515a, 515b, 515c can be less than the number of HX tubes in the third plurality of HX tubes 517a, 517b, 517c. Further, the first region 522 can be closer to the upstream side of the first slab 520, the third region 526 can be closer to the downstream side of the first slab 520, and the second region 524 can be between the first region 522 and the third region 526. The number of HX tubes in the first plurality of HX tubes 523a, 523b, 523c can be less than the number of HX tubes in the second plurality of HX tubes 525a, 525b, 525c. Additionally, the number of HX tubes in the second plurality of HX tubes 525a, 525b, 525c can be less than the number of HX tubes in the third plurality of HX tubes 527a, 527b, 527c. As will be appreciated, having fewer tubes in the regions of the slabs 510, 520, 530 with lower airflow will reduce the resistance in the lower airflow region therefore improving the airflow distribution of the heat exchanger system 500. As will be further appreciated, both the number and orientation of the HX tubes can be varied based on the airflow of the system 500.
As further depicted, the first region 612 can be closer to the upstream side of the first slab 610, and the second region 614 can be closer to the downstream side of the first slab 610. The diameter of each HX tube in the first plurality of HX tubes 613a, 613b, 613c can be less than the diameter of each HX tube in the second plurality of HX tubes 615a, 615b, 615c. Further, the first region 622 can be closer to the upstream side of the first slab 620 and the second region 624 can be closer to the downstream side of the first slab 620. The diameter of each HX tube in the first plurality of HX tubes 623a, 623b, 623c can be less than the diameter of each HX tube in the second plurality of HX tubes 625a, 625b, 625c. Further, the first region 632 can be closer to the upstream side of the first slab 630 and the second region 634 can be closer to the downstream side of the first slab 630. The diameter of each HX tube in the first plurality of FIX tubes 633a, 633b, 633c can be less than the diameter of each HX tube in the second plurality of HX tubes 635a, 635b, 635c. As will be appreciated, having tubes with smaller diameters in the region of the slabs 610, 620, 630 with lower airflow will reduce the resistance in the lower airflow region therefore improving the airflow distribution of the heat exchanger system 600. As will be further appreciated, both the number and orientation of the HX tubes can be varied based on the airflow of the system 600.
As further depicted, the first region 612 can be closer to the upstream side of the first slab 610 and the second region 614 can be closer to the downstream side of the first slab 610. The diameter of each HX tube in the first plurality of HX tubes 613a, 613b, 613c can be less than the diameter of each HX tube in the second plurality of HX tubes 615a, 615b, 615c. Further, the first region 622 can be closer to the upstream side of the first slab 620 and the second region 624 can be closer to the downstream side of the first slab 620. The diameter of each HX tube in the first plurality of HX tubes 623a, 623b, 623c can be less than the diameter of each HX tube in the second plurality of HX tubes 625a, 625b, 625c. As will be appreciated, having tubes with smaller diameters in the region of the slabs 610, 620 with lower airflow will reduce the resistance in the lower airflow region therefore improving the airflow distribution of the heat exchanger system 600. As will be further appreciated, both the number and orientation of the HX tubes can be varied based on the airflow of the system 600.
While various examples are described herein as having holes with a diameter (e.g., a circular hole), the holes can be of any shape and dimension. For example, one, some, or all of the holes for a particular slab can have a shape that is circular, ovular, square, rectangular, trapezoidal, polygonal, elliptical, triangular, irregular, or the like.
As further depicted, the first region 712 can be closer to the upstream side of the first slab 710 and the second region 714 can be closer to the downstream side of the first slab 710. The height and/or width of each microchannel HX tube in the first plurality of microchannel HX tubes 713a, 713b, 713c can be less than the height and/or width of each microchannel HX tube in the second plurality of microchannel HX tubes 715a, 715b, 715c. Further, the first region 722 can be closer to the upstream side of the second slab 720 and the second region 724 can be closer to the downstream side of the second slab 720. The height and/or width of each microchannel HX tube in the first plurality of microchannel HX tubes 723a, 723b, 723c can be less than the height and/or width of each microchannel HX tube in the second plurality of microchannel HX tubes 725a, 725b, 725c. Further, the first region 732 can be closer to the upstream side of the third slab 730 and the second region 734 can be closer to the downstream side of the third slab 730. The height and/or width of each microchannel HX tube in the first plurality of microchannel HX tubes 733a, 733b, 733c can be less than the height and/or width of each microchannel HX tube in the second plurality of microchannel HX tubes 735a, 735b, 735c. As will be appreciated, having tubes with smaller dimensions in the region of the slabs 710, 720, 730 with lower airflow will reduce the resistance in the lower airflow region therefore improving the airflow distribution of the heat exchanger system 700. As will be further appreciated, both the number and orientation of the HX tubes can be varied based on the airflow of the system 700.
As further depicted, the first region 712 can be closer to the upstream side of the first slab 710 and the second region 714 can be closer to the downstream side of the first slab 710. The height and/or width of each microchannel HX tube in the first plurality of microchannel HX tubes 713a, 713b, 713c can be less than the height and/or width of each microchannel HX tube in the second plurality of microchannel HX tubes 715a, 715b, 715c. Further, the first region 722 can be closer to the upstream side of the second slab 720 and the second region 724 can be closer to the downstream side of the second slab 720. The height and/or width of each microchannel HX tube in the first plurality of microchannel HX tubes 723a, 723b, 723c can be less than the height and/or width of each microchannel HX tube in the second plurality of microchannel HX tubes 725a, 725b, 725c. As will be appreciated, having tubes with smaller dimensions in the region of the slabs 710, 720 with lower airflow will reduce the resistance in the lower airflow region therefore improving the airflow distribution of the heat exchanger system 700. As will be further appreciated, both the number and orientation of the HX tubes can be varied based on the airflow of the system 700.
For example, and as depicted, air distribution device 840 can include a first region 842, a second region 844, a third region 846, and a fourth region 848. The first region 842 can include a plurality of openings 843a, 843b, 843c having a first dimension (e.g. diameter, width, height, etc.) to allow for air flow through the opening and to a portion of a slab. The second region 844 can include a plurality of openings 845a, 845b, 845c having a second dimension (e.g. diameter, width, height, etc.) to allow for air flow through the opening and to a portion of a slab. The third region 846 can include a plurality of openings 847a, 847b, 847c having a third dimension (e.g. diameter, width, height, etc.) to allow for air flow through the opening and to a portion of a slab. The fourth region 848 can include a plurality of openings 849a, 849b, 849c having a fourth dimension (e.g. diameter, width, height, etc.) to allow for air flow through the opening and to a portion of a slab. As will be appreciated, the shape and dimension of the openings can correspond to the distribution of airflow on the slabs. For example, the larger dimensioned openings can be positioned so as to direct larger portions of airflow onto the upstream portion of the slabs and the smaller dimensioned openings can be positioned so as to direct smaller portions of airflow on the downstream portion of the slabs. While the openings described herein are depicted as circular, the openings can be of any shape and dimension. For example, one, some, or all of the openings for a particular slab can have a shape that is circular, ovular, square, rectangular, trapezoidal, polygonal, elliptical, triangular, irregular, or the like.
The maldistribution of airflow can also be reduced by modifications to, or different designs for, the drain pan, which is used for collecting water droplets that drip from a heat exchanger system (e.g., condensate from the heat exchanger coils), such as the ones previously described, and discharging the water droplets external to the system.
As will be appreciated, such a design provides fin and coil assembly 1300 with an effective fin density (and thus an air-to-fin contact area) along the bottom coil portion B, which can be half that in the upper coil portion A. Accordingly, the velocity of the air which is being drawn by a fan or pushed by a blower through the bottom portion B of the fin and coil assembly 1300 can be substantially increased compared to the velocity that it would have in a conventionally configured coil in which the fin density was constant throughout the coil. This configuration of the fin and coil assembly 1300 provides a variety of advantages over conventionally configured coils including, for example, material cost savings, weight reduction, enhanced air side convective heat transfer, improved air velocity profiles, lowered air side pressure drop, improved condensate drainage efficiency, lowered frost and ice accumulation on the coil, and lowered thermal coil stress.
As will also be readily appreciated by those of ordinary skill in this particular art, a variety of modifications could be made to the representatively illustrated fin and coil assembly 1300 without departing from principles of the present invention. For example, only two fin sizes are used in the fin and coil assembly 1300. However, more than two fin sizes could be used, and the fins could be interdigitated in other manners, if desired. Further, fin and coil assembly 1300 has been show with two different portions A, B having different fin density, however more than two regions could exist. Further, while portions A, B are shown as discrete sections of differing fin density, the fin density can gradually change along the entire length of the assembly, as an alternative. Also, principles of the present invention could be advantageously utilized in coils having various geometries and orientations, such as for example, round coils, flat coils, coils which have non-vertical orientations, etc.
As will be appreciated, the examples presented herein have been directed at reducing the resistance of lower airflow region and increasing the distribution of airflow along the slabs in order to increase the performance of the heat exchangers. In addition to the previously discussed designs, the positioning of the blower can be adjusted to alter the distribution of airflow across the slabs. It will be appreciated that while certain examples have been distinctly shown and discussed, combining such examples falls within the scope of the present disclosure. For example, in some examples, a heat exchanger system could incorporate a combination of varying diameter HX tubes as well as varying numbers of rows of tubes.
Any component described in one or more figures herein can apply to any other figures having the same label. In other words, the description for any component of a figure can be considered substantially the same as the corresponding component described with respect to another figure. For any figure shown and described herein, one or more of the components can be omitted, added, repeated, and/or substituted. Accordingly, embodiments shown in a particular figure should not be considered limited to the specific arrangements of components shown in such figure.
In this description, numerous specific details have been set forth. It is to be understood, however, that implementations of the disclosed technology be practiced without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description. References to “one embodiment,” “an embodiment,” “some embodiments,” “example embodiment,” “various embodiments,” “one implementation,” “an implementation,” “example implementation,” “various implementations,” “some implementations,” etc., indicate that the implementation(s) of the disclosed technology so described may include a particular feature, structure, or characteristic, but not every implementation necessarily includes the particular feature, structure, or characteristic. Further, repeated use of the phrase “in one implementation” does not necessarily refer to the same implementation, although it may.
Terms such as “first,” “second,” “top,” “bottom,” “left,” “right,” “end,” “back,” “front,” “side”, “length,” “width,” “inner,” “outer,” “above”, “lower”, and “upper” are used merely to distinguish one component (or part of a component or state of a component) from another. Such terms are not meant to denote a preference or a particular orientation unless specified and are not meant to limit embodiments of water heating devices or heat exchangers. In the foregoing detailed description of the example embodiments, numerous specific details are set forth in order to provide a more thorough understanding of the disclosure. However, it will be apparent to one of ordinary skill in the art that the example embodiments can be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.
Accordingly, many modifications and other embodiments set forth herein will come to mind to one skilled in the art to which example water heaters pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that example water heaters are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of this application. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.