BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

[0001] The present invention relates to air-cooled coil-type heat exchangers. DESCRIPTION OF THE BACKGROUND

[0002] Air-cooled heat exchangers remove heat from a working fluid by transferring that heat to the air. Air-cooled heat exchangers typically consist of tubes connected to fins. The working fluid is sent through the inside of the tubes and the heat is conducted to the outside of the tubes and the fins. Air passing over the fins and tubes removes this heat; one or more fans are generally used to move the air. The working fluid can be a liquid, a gas, a condensing refrigerant, or any other fluid that needs to have heat removed. The tubes are typically constructed of copper, aluminum, or stainless steel but other metals and non-metals have been used. Fins are typically made from copper or aluminum but other thermally conductive materials have been used.

[0003] For heat to be removed from the working fluid, the temperature of the working fluid must be greater than the temperature of the air entering the cooler . The greater the temperature difference between the air entering the cooler and the working fluid the less is air volume needed to remove the heat; hence the less fan horsepower is needed to move the air.

SUMMARY OF THE INVENTION

[0004] According to the invention, there is presented a modular V-shaped heat exchange assembly in which a first, lower module contains two heat exchangers arranged in a V-shape, and a second upper module containing two additional heat exchangers is stacked on top of the first, lower module, and where the two heat exchangers in the upper module continue and extend the V-shape that is formed by the bottom two heat exchangers. The V shape results in more equal air flow through the heat exchanger. Finally, a fan module is placed atop the upper heat exchange module. According to various embodiments, the modules are factory pre-assembled, sized and configured for ease of shipping and assembly. The present invention provides substantially higher fluid flow rates and greater heat exchange capacity compared to prior art V-shaped air cooled heat exchangers using the same footprint, especially taking into account the required spacing between devices to allow for sufficient air flow. Multiple double V-stacked cells according to the invention may also be arranged in a line or rectangular array under one common fan with all air coming from the bottom .The invention may be used as a cooler for fluid cooling or as a condenser for refrigerant condensing. Optional adiabatic pads or adiabatic pre-cooling spray nozzles may be provided to pre-cool the air entering the system.

[0005] Accordingly, there is provided according to the invention, a modular V-shaped heat exchange apparatus featuring 1) a factory assembled and transportable bottom heat exchange module having a bottom module frame and two bottom module heat exchange panels arranged and supported in said bottom module frame in a V-shape, 2) a factory assembled and transportable top heat exchange module having a top module frame and two top module heat exchange panels arranged and supported in said top module frame so that said two top module heat exchange panels continue and extend the V-shape formed by said two bottom module heat exchange panels, said top heat exchange module positioned on and supported by said bottom heat exchange module; and 3) a factory assembled and transportable fan module having a fan module frame and at least one fan, said fan module positioned on top of and supported by said top heat exchange module, said at least one fan positioned and configured to draw air through said two bottom module heat exchange panels and said two top module heat exchangers. [0006] According to further features or embodiments of the invention, each of said two bottom module heat exchange panels and said two top module heat exchange panels have an inlet header and an outlet header, said inlet header configured and located to receive hot process fluid and to distribute it to a corresponding heat exchange panel and said outlet header configured and located to receive cooled process fluid from said heat exchange panel.

[0007] According to one embodiment of the invention each of said two bottom module heat exchange panels and said two top module heat exchange panels contain the same process fluid. [0008] According to other embodiments of the invention, at least one of said bottom module heat exchange panels and said top module heat exchange panels contains a first process fluid, and at least one other of the heat exchange panels contains a second process fluid different from said first process fluid.

[0009] According to further embodiments of the invention, at least one of the bottom module heat exchange panels and top module heat exchange panels contains a first process fluid, at least one of the other heat exchange panels contains no process fluid.

[0010] According to further embodiments of the invention, the modular V-shaped heat exchange apparatus may be fitted with adiabatic panels and/or spray nozzles configured to spray water into an air flow entering said bottom and top heat exchange modules.

[0011] According to another embodiment of the invention, each of said top module heat exchange panels share a common plane with an adjacent one of said bottom module heat exchange panels. [0012] According to yet another embodiment of the invention, there is provided 1) a plurality of a factory assembled and transportable bottom heat exchange modules, each having a bottom module frame and two bottom module heat exchange panels arranged and supported in said bottom module frame in a V-shape, 2) a plurality of factory assembled and transportable top heat exchange modules each having a top module frame and two top module heat exchange panels arranged and supported in said top module frame so that said two top module heat exchange panels continue and extend the V-shape formed by two of said two bottom module heat exchange panels, each of said plurality of top heat exchange modules positioned on and supported by a respective bottom heat exchange modules, and wherein said bottom and top heat exchange modules are configured to receive ambient air from below; 3) an elevating frame supporting each of said plurality of bottom heat exchange modules; and 4) a fan module comprising a single fan sized and positioned to draw air through a plurality of cells, each cell comprising a top heat exchange module and a bottom heat exchange module.

[0013] According to another embodiment of the invention, there is provided a method for assembling a heat exchange apparatus, comprising the steps of: transporting to an assembly location a factory assembled bottom heat exchange module having a bottom module frame and two bottom module heat exchange panels arranged and supported in said bottom module frame in a V-shape, transporting to said assembly location a factory assembled top heat exchange module having a top module frame and two top module heat exchange panels; transporting to said assembly location a factory assembled fan module having a fan module frame and at least one fan, installing said bottom heat exchange module at an installation location; mounting said top heat exchange module on top of said bottom heat exchange module, wherein said top module heat exchange panels are arranged and supported in said top module frame so that said two top module heat exchange panels continue and extend the V-shape formed by said two bottom module heat exchange panels; and mounting said fan module on top of said top heat exchange module.

[0014] There is further provided according to the invention a method for assembling a heat exchange apparatus, comprising: a. assembling an elevation frame at an installation location; b. mounting on said elevation frame a plurality of a factory assembled and transportable bottom heat exchange modules, each having a bottom module frame and two bottom module heat exchange panels arranged and supported in said bottom module frame in a V-shape, c. mounting on top of each of said bottom heat exchange modules a respective factory assembled and transportable top heat exchange module having a top module frame and two top module heat exchange panels arranged and supported in said top module frame so that said two top module heat exchange panels continue and extend the V-shape formed by two of said two bottom module heat exchange panels; d. and mounting and positioning above said top heat exchange module a fan configured to draw ambient air into a plenum formed by said elevation frame and up through a plurality of said bottom heat exchange modules and plurality of said top heat exchange modules. According to further embodiments of the invention, adiabatic pads may be mounted on said elevation frame. Alternatively or in addition, mounting spray nozzles may be mounted on said elevation frame and oriented said spray nozzles to spay water into air being drawn into or through the plenum.

BRIEF DESCRIPTION OF THE DRAWINGS [0015] Figure 1 is a perspective view of two V-type air cooled heat exchangers of the type that might be used in connection with the present invention. [0016] Figure 2 is a close up perspective view of the opposite ends of the two V-type air cooled heat exchangers shown in Figure 1.

[0017] Figure 3 is a representation of the operation of a V-type air cooled heat exchanger of the type shown in Figures 1 and 2.

[0018] Figure 4 shows a perspective view of two V-type air cooled heat exchangers on which adiabatic pads have been provided after market and site-mounted for pre-cooling the incoming air. [0019] Figure 5 shows a close-up side cutaway view of one of the V-type air cooled heat exchangers shown in Figure 3.

[0020] Figure 6 is a representation of the operation of the V-type air cooled heat exchanger with pre-cooling adiabatic pads shown in Figures 4 and 5.

[0021] Figure 7 is a representation of a standard fan size module according to an embodiment of the invention.

[0022] Figure 8 is a representation of a top heat exchange module according to an embodiment of the invention.

[0023] Figure 9 is a representation of a bottom heat exchange module according to an embodiment of the invention.

[0024] Figure 10 is a representation of a modular double V-stack air-cooled heat exchanger according to an embodiment of the invention.

[0025] Figure 11 is a representation of a modular double V-stack air-cooled heat exchanger with pre-cooling adiabatic pads according to an embodiment of the invention.

[0026] Figure 12 is a representation of a modular double V-stack air-cooled heat exchanger with pre-cooling adiabatic spray nozzles according to an embodiment of the invention. [0027] Figure 13 is a representation of a large fan module according to another embodiment of the invention.

[0028] Figure 14 is a representation of a modular double V-stack air-cooled heat exchanger according to a large fan module embodiment of the invention.

[0029] Figure 15 is a representation of a modular double V-stack air-cooled heat exchanger with pre-cooling adiabatic pads according to another large fan module embodiment of the invention. [0030] Figure 16 is a representation of a modular double V-stack air-cooled heat exchanger with pre-cooling adiabatic spray nozzles according to another large fan module embodiment of the invention.

[0031] Figure 17 is a representation of an embodiment of the invention in which multiple double- V-stack heat exchanger cells are mounted on an elevation frame beneath a very large fan.

[0032] Figure 18 is a representation of an embodiment of the invention in which an intermediate module may be placed between a top module and a bottom module to result in a triple V-stack air cooled heat exchanger.

[0033] Figure 19 is a representation of an embodiment of the invention in which one or more modules may have a second set of coils.

[0034] Features in the attached drawings are numbered with the following reference numerals:

101 bottom heat exchange module 113 bottom module frame top section

102 intermediate heat exchange module 115 bottom module frame side section

103 top heat exchange module 119 top corners of the bottom module frame 105 fan module 121 distance between tops of bottom heat

109 bottom heat exchange coil exchangers and top comers of bottom

111 bottom module frame base section module. 125 top heat exchange coil 161 water return tube

131 top corners of top frame module. 163 bottom module basin

133 The top module frame base section 165 pump

135 top module frame top section 167 large fan module

137 top module frame side sections 169 elevating frame

139 inlet header 171 very large fan module

141 outlet header 173 intermediate module frame

147 intermediate header 175 intermediate module heat exchange coil

151 adiabatic pre-cooling pad 177 low temperature process fluid coil

151a top adiabatic pad 179 high temperature process fluid coil

151b bottom adiabatic pads 181 space between high and low process fluid

153 top module water distribution tube coils.

157 spray nozzles

159 spray nozzle supply tube

DETAILED DESCRIPTION

[0035] An example of a V-shaped cooler is shown in Figs. 1 and 2. A frame supports two heat exchange panels (also “tube bundles” or “coils”), each comprising a plurality of horizontally arranged finned tubes in a V-shaped configuration. At one end of each tube bundle or coil, the tubes are connected at an inlet end to an inlet header and to an outlet header. At an opposite end of each bundle, each horizontal tube is connected to an adjacent horizontal tube via a return bend. A hot process fluid enters the inlet header via an inlet header connection and is then distributed to the tubes from the inlet header. Cooled fluid exits the tubes via an outlet header and returned to the process/ system that heated the fluid. The frame supports one or more fans at the top of the cooler and draws ambient air into the unit past the tubes and the fins and out the top of the unit. [0036] The principles of operation of a V-shaped air-cooled heat exchanger of the type shown in Figures 1 and 2 is shown in Figure 3. Hot process fluid, shown in red, enters the inlet header via the inlet header connection. From the inlet header, the hot process fluid travels transversely across the heat exchanger, generally parallel to the horizontal. Heat from the process fluid dissipates through the coil tubes’ surfaces and out to the fins (not shown). Ambient air is drawn over the coil surface by the fan(s) located at the top of the unit. Heat from the process fluid transfers to the air and discharged to the atmosphere. Cool process fluid, shown in blue, exits the unit through the outlet headers.

[0037] An example of a V-shaped cooler with adiabatic pre-cooling pads is shown in Figs. 4 and 5. A frame supports two heat exchange coils each comprising a plurality of horizontally arranged finned tubes in a V-shaped configuration. At one end of each tube bundle, the tubes are connected at an inlet end to an inlet header and to an outlet header. At an opposite end of each bundle, each horizontal tube is connected to an adjacent horizontal tube via a return bend. A hot process fluid enters the inlet header via an inlet header connection and is then distributed to the tubes from the inlet header. Cooled fluid exits the tubes via an outlet header and returned to the process/system that heated the fluid. Adiabatic pads are mounted along and spanning both sides of the unit lefit- to-right and top-to-bottom. A water distribution system drips water onto the top of the pads to saturate them. Water that is not evaporated from the pads is collected at the bottom of the unit and either send to drain or recirculated back to the top of the unit and returned to the pads. The frame supports one or more fans at the top of the cooler and draws ambient air into the unit through the saturated pads, past the tubes and the fins and out the top of the unit. [0038] The principles of operation of a V-shaped air-cooled heat exchanger with adiabatic pads for pre-cooling the incoming air is shown in Figure 6. Hot process fluid, shown in red, enters the inlet header via the inlet header connection. From the inlet header, the hot process fluid travels transversely across the heat exchanger, generally parallel to the horizontal. Heat from the process fluid dissipates through the coil tubes surface and out to the fins (not shown). The adiabatic system involves fully wetting a fibrous pad located in front of the coil. Ambient air is drawn through the adiabatic pre-cooling pad by the fans located on top of the unit. The air is humidified as it passes through the adiabatic pad, decreasing the dry bulb temperature within a few degrees of the wet bulb temperature. This new air temperature is referred to as the depressed dry bulb. This pre-cooled air is then drawn through the tube and fin surface, offering a substantial increase in heat rejection capability. Heat from the process fluid transfers to the air and discharged to the atmosphere. Cool process fluid, shown in blue, exits the unit through the outlet headers. In a recirculating water system, the water used to wet the adiabatic pads and which is not evaporated is collected at the bottom of the unit and recirculated to a water distribution system at the top of the pad. In a once- through water system, the water used to wet the adiabatic pads and which is not evaporated is collected and sent to a drain.

[0039] According to an alternate embodiment, instead of using adiabatic pads to pre-cool the incoming air, a V-shaped air-cooled heat exchanger may be outfitted with spray nozzles configured to spray a mist of water into the incoming air to humidify the ambient air before it is drawn past the fin and tube surfaces. A basin is situated at the bottom of the heat exchanger to collect and optionally recirculate the pre-cooling water to the spray nozzles via a recirculation pump, return pipes and water distribution pipes that distribute the pre-cooling water to the spray nozzles. According to an alternate once-through water system, the water sprayed into the incoming air and which is not evaporated is collected and sent to a drain.

[0040] Figures 7-10 show an embodiment in which the V-shaped air-cooled heat exchanger is formed from three modules, a bottom heat exchange module 101, a top heat exchange module 103, and a fan module 105. The bottom module 101 (Figure 9) includes a bottom module frame, and two bottom heat exchange coils 109 supported in the bottom module frame and arranged in a V- shape. The bottom module frame may include a base section 111, a top section 113 and side sections 115 extending between the base section 111 and the top section 113. The dimensions (width and length) of the top and bottom sections 111, 113 of the bottom module frame may be, but are not necessarily, the same. The tops of the two bottom heat exchange coils 109 do not converge with the top comers 119 of the bottom module frame but instead are separated from the side sections 115 of the bottom frame module by a distance 121.

[0041] The top module 103 (Figure 8) includes a top module frame, and two top heat exchange coils 125 supported in the top module frame so that they continue and extend the V-shape formed by the two bottom heat exchange coils 109 when the top heat exchange module 103 is placed on top of the bottom heat exchange module 101. The top heat exchange module 103 is dimensioned to fit on top of and be supported by the bottom heat exchange module 101. The top heat exchange coils 125 are inclined away from one-another from bottom to top. The bottoms of the top heat exchanger coils 125 are spaced from one-another approximately the same distance 121 that the tops of the bottom heat exchangers 109 are spaced from one-another. The tops of the top heat exchangers 125 preferably terminate at opposite top comers 131 of the top frame module. The top module frame may include a base section 133, a top section 135 and side sections 137 extending between the base section 133 and the top section 135. The dimensions (width and length) of the top and bottom sections of the top module frame may be, but are not necessarily, the same as one- another, and may be the same as the dimensions of the top and bottom sections of the bottom module frame. According to a preferred embodiment, the base section 133 of the top module frame is configured to mate with and be fixed to the top section 113 of the bottom module frame. [0042] Each of the four heat exchange coils (two top coils 125 and two bottom coils 109) may include a dedicated inlet header 139 (shaded in red/stippling) and outlet header 141 (shaded in blue/crosshatch) connected by a plurality of tubes with horizontal segments and U-shaped return bends.

[0043] According to one embodiment, adjacent top and bottom coils are fluidically isolated from one-another. According to one aspect of this embodiment, the coils may be manufactured with different materials compatible with the process fluid allowing multiple different process fluids to be cooled in a single assembly.

[0044] According to another embodiment, the fluid to be cooled in a top heat exchange coil 125 may pass from the outlet header 141 of the top heat exchange coil 125 to the inlet header of the adjacent bottom heat exchange coil 109 via an intermediate header 147.

[0045] A fan module 105 (Figure 7) is dimensioned and configured to rest upon and be supported by the top module 103.

[0046] According to a first optional embodiment of the invention, the double-v stack heat exchanger of the invention may be provided with adiabatic pre-cooling pads, see, e.g., Fig. 11. According to another optional embodiment of the invention, each of the top and bottom modules may be fitted with adiabatic pre-cooling pads 151a and 151b, see, e.g., Fig. 15. According to this embodiment, a top module water distribution tube 153 is located above the top adiabatic pre cooling pads 151a and drips or sprays water onto the top adiabatic pads. According to a first variation to this embodiment, the water that passes through the top adiabatic pads 151a drains into the bottom adiabatic pads 151b. According to a second variation of this embodiment (not shown), the water passing through the top adiabatic pads 151a is collected in top module water collection trays and redistributed to the bottom module adiabatic pads 151b.

[0047] According to another optional embodiment (Figure 12), instead of having adiabatic pre cooling pads, the top and bottom modules may be provided with a pre-cooling spray system including spray nozzles 157 located and configured to spray water into the incoming air flow.

The spray nozzles 157 may be attached to and fed by spray nozzle supply tubes 159 which receive fresh water from a fresh water supply or, in the case that unused water collected in a water collection basin, water return tubes 161.

[0048] According to one embodiment, each of the top and bottom modules may have separate and independent water supply, collection and water recirculation (or drain) systems, whether using adiabatic pads or adiabatic pre-cooling spray nozzles. According to an alternate embodiment, there may be an integrated water supply collection and recirculation (or drain system) in which all water supplied to the system is collected at the bottom of the bottom module in a basin or set of trays 163, and drained, or returned to various water distribution locations in the top and bottom modules via water return tubes 161 supplied by one or two pumps 165 located in the bottom module.

[0049] Figure 13 shows a large fan module 167 which may be used in place of the module 105 of Figure 7 in which two or more smaller fans are used. In the large fan module embodiment, the fan or fans have a diameter that is greater than 60% of the distance that separates the tops of the two top heat exchangers 126. As with the embodiment of Figure 7, the large fan module 167 is dimensioned and configured to rest upon and be supported by the top heat exchange module 103. Figures 14-16 show large fan embodiments corresponding to the otherwise identical embodiments of Figures 10-12.

[0050] According to another embodiment of the invention, represented in Figure 17, multiple top and bottom heat exchange modules may be mounted adjacent to one another in a line or in a rectangular matrix on a elevating frame 169. According to this embodiment, a single very large fan module 171 may be positioned on top of a matrix of V-shaped modular heat exchangers to draw air into and through the open space created by the elevating frame 169 and up through the plurality of bottom and top heat exchange modules. In the case of the this embodiment, a single fan draws air through at least two, and preferably three, four, five or six double v-stacked cells. The bottom elevated air sections may be equipped with adiabatic pre-cooling pads and/or sprays to pre-cool the entering air.

[0051] According to another embodiment of the invention, represented in Figure 18, one or more intermediate heat exchange modules 102 may be placed between the top and bottom heat exchange modules 101, 103 to result in triple, quadruple, or more V-stacked air-cooled heat exchangers. According to this embodiment, each intermediate heat exchange module 102 includes intermediate heat exchange coils 175 supported in an intermediate module frame 173. The triple, quadruple or more V-shaped stacked modular air-cooled heat exchanger according to the invention may have a single very large fan module, or a fan module with two or more fans. Additionally, the triple, quadruple or more V-shaped stacked modular air-cooled heat exchanger according to the invention, may be optionally fitted with adiabatic pads or adiabatic spray systems as described above.

[0052] According to another embodiment of the invention, one or more of the heat exchange modules in a V-shaped stacked modular air-cooled heat exchanger of the invention may include a second set of coils nested proximate the first set of coils, separated by a space. According to this embodiment, a bottom, top or intermediate module (or combination thereof) has a set of low temperature process fluid coils 177, and a second set of high temperature process fluid coils 179. The low temperature process fluid coils 177 are preferably located on the air intake side of the module and the high temperature process fluid coils 179 are located on a plenum side of the module. According to this embodiment, ambient air drawn into the module, for example at 80°F, first passes through the low temperature process fluid coils 177, cooling the low temperature process fluid, for example from 100°F to 90°F, warming the air to 88°F. The warmed air then passes through a space 181 between the coils and then passes through the high temperature process fluid coils 179, cooling the hot process fluid, for example, from 130°F to 115°F, further heating the ambient air which leaves the module now heated to, for example 110°F. It is noted that the air and process fluid temperatures mentioned above are merely for exemplary purposes. The high temperature process fluid and the low temperature process fluid may be different fluids entirely, generated by different process. Alternatively, the low temperature process fluid may be the same fluid as the high temperature process fluid, in which the process fluid first flows through a high temperature process fluid coil, and subsequently through a low temperature process fluid coil.

[0053] It is specifically contemplated that every feature embodiment disclosed herein may be used together with every other feature and embodiment disclosed herein.

[0054] The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the concept of a modular double-V-stacked cooler or condenser are intended to be within the scope of the invention. Any variations from the specific embodiments described herein but which otherwise constitute modular double-V-stacked cooler or condenser should not be regarded as a departure from the spirit and scope of the invention set forth in the following claims.