Patent Application
20170227292
Not applicable.
a. Field of Invention
The invention relates generally to the field of process fluid cooling. More particularly, the invention refers to heat exchange systems and methods for cooling fluids using a compact cabinet using less space, height, and weight than other heat exchange systems known in the art.
Current State of the Art
In a traditional counter flow closed circuit fluid cooler, the air comes into the cabinet through inlet louvers located below the heat exchanger. The air is drawn up first through the heat exchanger, then the water spray, and finally across mist eliminators before being discharged through the fans.
Because the inlet air louvers are located below the heat exchanger coil and in the wet air stream, it is possible for water to splash out, or during windy periods to be blown out. This arrangement also requires more unit height to stack all of the areas one over the other.
U.S. Pat. No. 5,501,269 to Jenkens discloses a condenser unit configuration having double wall sidewalls wherein outside air is drawn into the cabinet above the sprayers. This configuration does prevent sunlight reaching the sump water as well as sump water splashing out the inlet louvers by using the double side walls to bring in the outside air through inlets near the top of the walls. Air enters at top of wall and travels downward through double wall void to bottom opening cut in inside wall. The air then travels up through the heat exchanger coil similar to conventional closed circuit fluid coolers.
It is desirable to have a heat exchange system that overcomes loss of spray water and also have a lower overall unit height.
One object of the invention is to provide a compact heat exchange system that minimizes loss of spray water, is efficient, and has a compact height, compact footprint, and provides less weight loading to a roof or other structure supporting the system.
The invention is directed to a heat exchange system for cooling heated fluid circulated from a heat source. The term heated fluid, could be, but is not limited to water, glycol, oil, or refrigerant. A vertically oriented central plenum is housed within a base structure, a plurality of upright side panels, and a top. The central plenum and the plurality of side panels define boundaries of a coil-air interface that houses a heat exchange coil. Above the heat exchange coil are sprayers that spray/distribute water downwardly over the heat exchange coil into the base structure, where the water is collected and pumped back to the sprayers. The plurality of side panels have air intakes that communicate outside air into the coil-air interface at a location above the sprayers and the heat exchange coil. A fan connected to the plenum draws air through the air intake, downwardly over the heat exchange coil located in the coil-air interface, generally horizontally into the plenum at an intake conduit, and then vertically to a central exhaust exit of the plenum.
The plenum can be described as including at least one horizontally-disposed lower located intake conduit that transitions to a vertically oriented exhaust conduit. The at least one intake conduit is for drawing air into the plenum. The at least one intake conduit is defined by at least one wall extending from a face opening, in a generally horizontal direction, to an intake transition end. The exhaust conduit conveys air from the at least one intake conduit The exhaust conduit is defined by at least one central exhaust wall that extends generally vertically from a central exhaust transition end to a central exhaust exit. The transition is defined by at least one transition wall that extends from generally horizontal at the intake transition end to generally vertical at the central exhaust transition end.
In an embodiment of the present invention heat exchange system, mist eliminators are disposed within the at least one intake conduit of the plenum. The mist eliminators are defined as a plurality of surfaces that are oriented to create a flowpath by which mist-entrained air travels as the mist-entrained air is drawn through the at least one intake conduit of the plenum. The plurality of surfaces are generally parallel and have angular bends that vary the flowpath in a directional manner causing the mist-entrained air to impinge on the surfaces as the mist-entrained air travels through the flowpath, causing a mist to collect (or transfer) onto the surfaces. According to an embodiment of the present invention, the surfaces have a pitch that causes the mist to drain in a direction away from the centrally located exhaust conduit. In other words, the surfaces are generally higher in elevation at a central end than elevation at an intake end. In an embodiment of the present invention, the plenum includes a coil support surface for providing structural support to heat exchange coil equipment. The coil support surface is defined by a flange that protrudes outwardly from the centrally located exhaust conduit. The flange, preferably, is integral to the at least one wall forming the at least one intake conduit.
In an embodiment of the present invention, the plenum includes a coalescing structure located within the centrally located exhaust conduit for removing fluid that is entrained within air passing through the exhaust conduit. The coalescing structure comprises a helical strip.
In accordance with an embodiment of the present invention heat exchange system, a base structure is disclosed. The base structure is for aiding in the collection and redistribution of the spray water, and for supporting the side panels and the plenum. The base structure comprises a floor existing at a first average floor elevation and a plurality of upturned edges extending upwardly from the periphery of the floor and creating a catchment area. A raised plateau structure (RPS), (formed into or with or as a part of the floor) extends upwardly from the floor. The RPS forms a plenum support surface. The plenum support surface exists at a PSS elevation that is above the first average floor elevation. The RPS is located central to the base and occupies a RPS area less than the catchment area. A sump recess is located within the catchment. The sump recess has a SR floor existing at a sump average elevation that is lower than the first average floor elevation. The sump recess has at least one SR wall for communicating fluid from the floor to the SR floor. The drain conduit communicates fluid from the SR floor to a drain.
In accordance with an embodiment of the present invention, the base structure includes a standpipe. The standpipe comprises a conduit extending generally upwardly through the base structure to a top. The conduit has an aperture at an overflow elevation for communicating fluid into the conduit to the drain when the fluid reaches the overflow elevation.
In accordance with an embodiment of the present invention, the base structure includes a bleed off catchment defined by an expandable structure in fluidic communication with a waste conduit. The expandable structure is disposed to intercept (catch/receive/collect) a portion of the spray water falling to the floor of the base structure and convey the portion to the waste conduit. According to a preferred embodiment, the expandable structure of the bleed off catchment includes a manual setting structure to enable selective adjustment of the amount by which the plurality of surfaces overlap each other.
In accordance with an embodiment of the present invention, the base structure includes fork lift fork receiving channels. Said receiving channels are preferably located at a fork channel elevation below the drain recess. This is to minimize or eliminate any additional catch basin volume created by having the receiving channels above the drain recess.
In accordance with an embodiment of the present invention heat exchange system, a side panel is disclosed. The side panel comprises an outer surface extending between side edges from a bottom outer edge to a top outer edge, an inner surface extending between side edges from a bottom inner edge to a top inner edge, and an air intake connecting the outer surface to the inner surface for communicating outside air through the side panel into a coil-air interface space. The inner surface forms a protrusion that extends inwardly to define a cavity forming face and at least one adjoining face. The cavity forming face forms the outer boundary of the coil-air interface space when a plurality of side panels are positioned together on the base structure. The adjoining face is for abutting (or near abutting) another adjoining face of another side panel to minimize openings where spray water can leak outside the cabinet.
In accordance with an embodiment of the present invention, a method for cooling hot fluid circulated in a heat exchange coil is disclosed. The method comprises drawing air with a fan coupled to (or contained in or formed as) the plenum from a location outside of the cabinet. The air flowing into an air intake located on an upper portion a side panel of the plurality, into the coil-air interface containing the heat exchange coil i.) downwardly from the air intake over (through) the heat exchange coil, ii.) generally horizontally-inwardly through at least one intake conduit of the plenum from a face opening to an intake transition end, and iii.) vertically through a centrally located exhaust conduit for from a central exhaust transition end to a central exhaust exit. The method further includes, in the heat exchange cabinet, spraying water downwardly into the coil-air interface and on the heat exchange coil. The method further includes, in the heat exchange cabinet, collecting water sprayed on the heat exchange coil in a base structure, and returning water to the sprayers.
According to an embodiment of the present invention, a method for cooling hot fluid (water, glycol, oil or refrigerant) circulated in a heat exchange coil is disclosed. A coalesced stream of spray water and air is drawn downwardly over a heat exchange coil that surrounds a central exhaust plenum. The plenum is defined by a central exhaust wall that physically separates a plenum flowpath from the heat exchange coil. After passing downwardly through the coil, a portion of the spray water is separated from the air by drawing the air generally horizontally inward from a face opening through an intake conduit, to an intake transition end, while allowing a portion of the spray water to fall by gravity below the face opening of the intake conduit. The air is then drawn upwardly within the plenum from the intake transition end to an exhaust external to the enclosure. The spray water is then collected in a base structure and recirculated to the sprayers with a pump.
According to an alternate embodiment of the present invention, a heat exchange system is disclosed. The heat exchange system comprises a heat exchange cabinet. The heat exchange cabinet is defined by a vertically oriented central plenum housed within a base structure, a plurality of upright side panels, and a top. The central plenum and the plurality of side panels define boundaries of an coil-air interface that exists within the cabinet external to the plenum. A plenum coil-air interface is defined within the central plenum. A first HX coil is located in the plenum coil-air interface. The first HX coil is adapted to convey fluid from a HX1 inlet through a plurality of tubes to a HX1 outlet. A second HX coil is located in the coil-air interface. The second HX coil is adapted to convey fluid from a HX2 inlet through a plurality of tubes to a HX2 outlet. A third HX coil is located in the coil-air interface. The third HX coil is located above or below the second HX coil and is adapted to convey fluid from a HX3 inlet through a plurality of tubes to a HX3 outlet. Plumbing is provided and adapted to convey the heated fluid from a cabinet inlet to the first HX coil at a HX1 inlet, then from the HX1 outlet to the HX2 inlet, then from the HX2 outlet to the HX3 inlet, then from the HX3 outlet to a cabinet outlet. In operation, a plurality of sprayers spray water into the coil-air interface; a fan connected to the plenum causes air to be drawn from outside the cabinet downwardly with water from the sprayers through the coil-air interface over the second and third HX coils, into the plenum at an intake conduit, and then upwardly the plenum coil-air interface over the first HX coil to a central exhaust exit of the plenum at the top; and the heated fluid is circulited via the plumbing from a cabinet inlet to the first HX coil at a HX1 inlet, then from the HX1 outlet to the HX2 inlet, then from the HX2 outlet to the HX3 inlet, then from the HX3 outlet to a cabinet outlet.
According to an alternate embodiment of the present invention, a method for cooling hot fluid (water, glycol, oil or refrigerant) circulated in a heat exchange coil is disclosed. The method comprises the steps of providing a heat exchange cabinet, drawing a coalesced stream of spray water and air downwardly through the coil-air interface, over a second HX coil and third HX coil contained within the coil-air interface. After passing downwardly through the coil-air interface, a portion of the spray water is separated from the air by drawing the air generally horizontally inward from a face opening through an intake conduit, to an intake transition end, while allowing a portion of the spray water to fall by gravity below the face opening of the intake conduit. Air is drawn upwardly through the plenum coil-air interface, over the first HX coil, from the intake transition end to an exhaust external to the enclosure. A hot fluid from a heat source is conveyed to the first HX coil, then to the second HX coil, then to the third HX coil, then back to the heat source.
Additional features, advantages, and embodiments of the invention may be set forth or apparent from consideration of the following detailed description. Moreover, it is to be understood that both the foregoing summary of the invention and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the invention.
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate preferred embodiments of the invention and together with the detailed description serve to explain the principles of the invention. In the drawings:
Referring now to the Figures in general, and specifically to
Referring to
Important to the design of the heat exchange system 10 are the areas of the exhaust conduit 213 and the face opening(s) 209 of the plenum 200. The central plenum 200 has an exhaust plenum face area defined as the cross sectional area within exhaust conduit 213 formed by the at least one central exhaust wall 215. The plenum 200 having an intake conduit 213 total face area defined by the sum of the area of the face opening(s) 209 of the at least one intake conduit 205 and one or more additional areas of additional face openings 209 of additional intake conduits 205 of the plenum 200. The total face area of the intake conduit(s) 205 should be maximized to slow the velocity of the mist-entrained air that enters the plenum 200 at the intake conduit(s). Decreased air velocities into the intake conduit(s) will result in improving separation of water/mist from the airflow/airstream as it enters the plenum 200. Also, smaller areas result in higher air velocities, which contribute to noise.
Alternately stated, the plenum has a total face area defined summing the area of the face opening 209 of the at least one intake conduit 205, and also summing one or more additional areas of additional face openings 209. Ideally, the total face area for a given unit height is larger than a surface area of the central exhaust conduit 213 for the same given unit height. This is to minimize a face opening air velocity, that is dependent on said total face area for a given height, to promote the de-entrainment of spray water from the air entering the plenum.
Also important to the design of the heat exchange system 10 is the area of the coil-air interface 15. The coil-air interface 15 has a coil face area defined as the area between the central plenum 200 and the plurality of side panels 300. According to known principles of heat transfer theory, this area is important for determining overall heat exchange from the size of the heat exchange coil 19 that can fit within the coil-air interface 15.
In a preferred embodiment of the present invention, the fan 53 draws air through the coil-air interface 15 at a coil velocity range between about 400-800 fpm. Ideally, the ratio of coil face area to exhaust plenum face area is in the range from about 2 to 1-3.5 to 1. The intake conduit 205 total face area of the plenum 200 is large enough to pass the air through the intake conduit 205 total face area at a velocity of 1,500 fpm or less, and optimally at 850 fpm or lower. Further, the intake conduit 205 total face area is no less than about 43% of the coil face area, and optimally about 77% of the coil face area. The plenum 200 optimally has the ratio of exhaust plenum face area to the intake conduit total face area within the range of about 1 to 2, or 40%-60%.
Referring to
In a preferred embodiment of the present invention, the plenum 200 includes an air inlet frame 229 (
In an embodiment of the present invention, the plenum 200 further includes a plenum base 239 (
In an embodiment of the present invention, the plenum 200 includes a coil support surface 261 (
In an embodiment of the present invention, the plenum 200 includes a coalescing structure 263 (
Referring to
A sump recess 119 is located within the catchment 109. In an embodiment, the sump recess 119 is located inside or outside the RPS area 117. The sump recess 119 has a SR floor 121 existing at a sump average elevation 123 that is lower than the first average floor elevation 103. The sump recess 119 has at least one SR wall 125 for communicating fluid from the floor 1012 to the SR floor 121. SR wall 125 includes, within the understanding of this description, a conduit or open channel that conveys fluid. The drain conduit 135 communicates fluid from the SR floor 121 to a drain. The drain conduit 135 includes, within the meaning of this description, a conduit or open channel that conveys fluid.
Referring to
In accordance with an embodiment of the present invention, the base structure 100 includes a bleed off catchment 145 defined by an expandable structure 147 in fluidic communication with a waste conduit 149. The expandable structure 147 is disposed to intercept (catch/receive/collect) a portion of the spray water falling to the floor 101 of the base structure 100 and convey the portion to the waste conduit 149.
In a preferred embodiment, the expandable structure 147 of the bleed off catchment 145 is defined by a plurality of overlapping part surfaces 151. A total surface area of the expandable structure 147 exposed to intercept the portion of the spray water is inversely proportional to the an amount by which the plurality of surfaces 151 overlap each other of the plurality of surfaces 151.
According to a preferred embodiment, the expandable structure 147 of the bleed off catchment 145 includes a manual setting structure 153 to enable selective adjustment of the amount by which the plurality of surfaces 151 overlap each other. In a preferred embodiment, the manual setting structure 153 includes: a slot 155 formed into at least one surface 151 of the plurality of overlapping part surfaces 151; a threaded member 157 passing through the slot 155; and one or more thread cooperating members 159 for fixing the at least one surface 151 of the plurality of overlapping part surfaces 151 to an other surface 151 of the plurality of overlapping part surfaces 151.
According to an embodiment of the present invention, the expandable structure 147 of the bleed off catchment 145 includes: a first partial box surface 163, and a second partial box surface 173. The first partial box surface 163 includes a bottom 163a and three sides 163b extending upwardly from the bottom 163a, thereby leaving an open top 163c and an open end 163d. The second partial box surface 173 includes a bottom 173a and three sides 173b extending upwardly from the bottom 173a, thereby leaving an open top 173c and an open end 173d. One of the first partial box surface 163 and second partial box surface 173 has a open end width 175 that is larger than an other open end width 177 to enable one of the first partial box 163 and second partial box 173 to slide within an other of the first partial box 163 and second partial box 173. One of the first partial box surface 163 and second partial box surface 173 has a waste conduit fitting 179 in the bottom 163a/173a to fluidically couple with the waste conduit 149.
In an embodiment of the present invention, the bleed off catchment further includes a waste conduit fitting 179 and an aperture 141. The waste conduit fitting 179 formed into (connected to or formed part of) the expandable structure 147. The waste conduit fitting 179 having at least one wall 181 communicating an expandable structure top surface 183 to a waste conduit fitting outlet 185. The aperture 141 is for communicating fluid into the waste conduit fitting to the waste conduit fitting outlet 185 when the fluid reaches the aperture 141. In a preferred embodiment, the aperture 141 is located below the expandable structure 147.
In accordance with an embodiment of the present invention, the base structure 100 includes fork lift fork receiving channels 187 (
Referring to
In a preferred embodiment, the side panel 300 further includes a base coupling interface 325 for coupling the side panel 300 to the base structure 100, or a sill 326 that connects with the base structure 100. The base coupling interface 325 is defined by or comprises one or more of a bottom outer edge 305 that is offset vertically from the bottom inner edge 311 by one or more base lip surfaces 327. The base coupling interface 325 includes one or more of tabs, recesses, keys, or keyways 329; one or more lap joints 329; and one or more threaded nut inserts 329a molded into the side panel 300.
In a preferred embodiment, the side panel 300 further includes one or more races, chases and/or recesses 331 extending vertically through the protrusion 319 for providing a pathway for piping, tubing or electrical cabling. Preferably, the one or more races, chases and/or recesses 331 are formed integral to the panel 300 by means of rotational molding.
The side panel 300 further has an inner side edge 333 and an outer side edge 335, wherein the inner side edge 333 is offset from the outer side edge 335 by one or more side lip surfaces 337 to enable overlapping and secure inter-fitment among adjoining side panels 300 or other structures. In a preferred embodiment, the protrusion 319 has a portional cross-sectional shape of an arc, a partial arc, and/or a semicircle to encompass a circular heat exchange coil. The protrusion 319 may have a support abutment, notch groove, recess, or ledge 339 for providing vertical load bearing support to one or more support structures that span inwardly from one side panel to another side panel. The side panel 300 preferably includes a top coupling interface 341 for coupling the side panel 300 to a top 400. The top coupling interface 341 is defined by or comprises one or more of:
In accordance with an embodiment of the present invention, a method for cooling hot fluid (water, glycol, oil or refrigerant) circulated in a heat exchange coil is disclosed. The method comprises providing a heat exchange system 10/cabinet 13 as disclosed herein. Then, drawing air with a fan 23 coupled to (or contained in or formed as) the plenum 200 from a location outside of the cabinet 13, into an air intake 315 located on an upper portion a side panel 300 of the plurality of side panels 300, into the coil-air interface 15 containing the heat exchange coil 319 i.) downwardly from the air intake 315 over (through) the heat exchange coil 19, ii.) generally horizontally-inwardly through at least one intake conduit 205 of the plenum 200 from a face opening 209 to an intake transition end 311, and iii.) vertically through a centrally located exhaust conduit 213 for from a central exhaust transition end 317 to a central exhaust exit 319. The method further includes, in the heat exchange cabinet 13, spraying water downwardly into the coil-air interface 15 and on the heat exchange coil 19. The method further includes, in the heat exchange cabinet 13, collecting water sprayed on the heat exchange coil 19 in a base structure 100, and returning water to the sprayers 21.
According to an embodiment of the present invention, a method for cooling hot fluid (water, glycol, oil or refrigerant) circulated in a heat exchange coil 19 is disclosed. A coalesced stream of spray water and air is drawn downwardly over a heat exchange coil 19 that surrounds a central exhaust plenum 200. The plenum 200 is defined by a central exhaust wall 215 that physically separates a plenum flowpath from the heat exchange coil 19. After passing downwardly through the coil 19, a portion of the spray water is separated from the air by drawing the air generally horizontally inward from a face opening 209 through an intake conduit 205, to an intake transition end 211, while allowing a portion of the spray water to fall by gravity below the face opening 209 of the intake conduit 205. The air is then drawn upwardly within the plenum 200 from the intake transition end 211 to an exhaust 203 external to the enclosure 13. The spray water is then collected in a base structure 100 and recirculated to the sprayers 21 with a pump.
Referring now to
An advantage of such a configuration disclosed herein is that it allows the hottest fluid to reach the air in the plenum 200 first, after the air has been wetted. The hot coil (first HX coil 25) helps to heat the wet air stream well above its saturation temperature and thus mitigates plume formation above the exhaust exit 219 of the cabinet 13 on cold winter days. The air is better utilized in the cabinet 13, allowing the air stream to carry off the hottest air last, rather than through the cabinet. The liquid from the heat source 10, after exiting the first HX coil 25, is cooled some before entering the second HX coil 27 and third HX coil 29 located in the wetted coil-air interface 19 reducing the tendency to build scale on the second HX coil 27 and third HX coil 29. Moreover, drier air is exhausted from the plenum 200 past the fan 53 motor, which results in lower fan motor bearing and winding dedregation.
Plumbing 31 is provided and adapted to convey the heated fluid from a cabinet inlet 33 to the first HX coil 25 at a HX1 inlet 25a, then from the HX1 outlet 25b to the HX2 inlet 27a, then from the HX2 outlet 27b to the HX3 inlet 29a, then from the HX3 outlet 29b to a cabinet outlet 35.
In operation, a plurality of sprayers 21 spray water into the coil-air interface 15; a fan 53 connected to the plenum 200 causes air to be drawn from outside the cabinet 13 downwardly with water from the sprayers 21 through the coil-air interface 15 over the second and third HX coils 27, 29, into the plenum 200 at an intake conduit 205, and then upwardly through the plenum coil-air interface 17 over the first HX coil 25 to a central exhaust exit 219 of the plenum 200 at the top 400. The heated fluid is circulited via the plumbing 31 from a cabinet inlet 33 to the first HX coil 25 at a HX1 inlet 25a, then from the HX1 outlet 25b to the HX2 inlet 27a, then from the HX2 outlet 27b to the HX3 inlet 29a, then from the HX3 29b outlet to a cabinet outlet 35.
Referring to
Referring to
Referring again to
The tubes 41 may be polymer type or metal, such as stainless steel or copper. Preferably, the plenum 200, base 100, walls 300 and top 400 are polymer.
The invention further includes a method for cooling fluid circulated from a heat source 10 comprises, in an enclosure or cabinet 13: drawing a coalesced stream of air and fluid spray downwardly over a heat exchange medium that surrounds a central exhaust plenum 200, the plenum 200 defined by a central exhaust wall 215 that physically separates a plenum flowpath from the heat exchange medium. The heat exchange medium may be a heat exchange coil, or slab, tubes, or tower fill located in the coil-air interface 15. After passing downwardly over the heat exchange medium, a portion of the fluid spray is separated from the air by drawing the air generally horizontally inward from a face opening through an intake conduit, to an intake transition end, while allowing a portion of the fluid spray to fall by gravity below the face opening 209 of the intake conduit 213. Air is drawn upwardly within the plenum 200 to an exhaust 203 external to the enclosure 13. The fluid is then collected in a base structure 100 and returned the fluid to the heat source 10.
Although particular embodiments of the invention have been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those particular embodiments, and that various changes and modifications, including the omission of steps or the interchangeability of the order of steps, may be effected therein by one skilled in the art without departing from the scope or spirit of the invention.
This application claims priority to U.S. Provisional Patent Application No. 62/058,174, filed Oct. 1, 2014; U.S. Provisional Patent Application No. 62/064,609 filed on Oct. 16, 2014, and 62/194,558 filed on Jul. 20, 2015; and incorporates the same by reference as if set forth herein in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US15/53602 | 10/1/2015 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62058174 | Oct 2014 | US | |
| 62064609 | Oct 2014 | US | |
| 62194558 | Jul 2015 | US |
