HEAT EXCHANGER COIL ARRAY AND METHOD FOR ASSEMBLING SAME

Abstract

A heat exchanger coil array includes at least six heat exchanger coils of an HVAC&R system for regulating a temperature of a structure, each heat exchanger coil being a separate and independent unit, where each heat exchanger coil is less than 75 pounds and capable of being moved within a passageway of the structure, the passageway having a width along at least a portion of the passageway of about 44 inches, and where an assembled heat exchanger coil array is incapable of being moved within the passageway.

Claims

1. A heat exchanger coil array comprising: at least six heat exchanger coils of an HVAC&R system for regulating a temperature of a structure, each heat exchanger coil being a separate and independent unit; and wherein each heat exchanger coil is less than 75 pounds and capable of being moved within a passageway adjacent to the HVAC&R system, the passageway having a width along at least a portion of the passageway of about 44 inches.

2. The heat exchanger coil array of claim 1, wherein the width along at least a portion of the passageway is about 36 inches.

3. The heat exchanger coil array of claim 1, wherein the width along at least a portion of the passageway is about 28 inches.

4. The heat exchanger coil array of claim 1, wherein each heat exchanger coil is independently selectably connectable to receive fluid from a fluid source of the system.

5. The heat exchanger coil array of claim 1, wherein the heat exchanger coil array operates as a condenser.

6. The heat exchanger coil array of claim 1, wherein the heat exchanger coil array operates as an evaporator.

7. The heat exchanger coil array of claim 1, wherein each heat exchanger coil has an individual operating capacity between 10% and 20% of an overall operating capacity of the heat exchanger coil array.

8. The heat exchanger coil array of claim 1, wherein at least one heat exchanger coil of the at least six heat exchanger coils has an operating capacity of about 2,000 CFM.

9. The heat exchanger coil array of claim 1, wherein at least one heat exchanger coil of the at least six heat exchanger coils weighs about 50 pounds or less.

10. The heat exchanger coil array of claim 1, wherein at least one heat exchanger coil of the at least six heat exchanger coils weighs about 40 pounds or less.

11. The heat exchanger coil array of claim 1, wherein at least one heat exchanger coil of the at least six heat exchanger coils weighs about 35 pounds or less.

12. An air handler comprising: at least six heat exchanger coils of an HVAC&R system for regulating a temperature of a structure, each heat exchanger coil being a separate and independent unit; wherein each heat exchanger coil is independently selectably connectable to receive fluid from a fluid source of the system; and wherein each heat exchanger coil comprises an individual operating capacity between 10% and 20% of an overall capacity of the air handler and is capable of being moved within a passageway adjacent to the HVAC&R system, the passageway having a width along at least a portion of the passageway of about 44 inches.

13. The air handler of claim 12, wherein the width along at least a portion of the passageway is about 36 inches.

14. The air handler of claim 12, wherein the width along at least a portion of the passageway is about 28 inches.

15. The air handler of claim 12, wherein each heat exchanger coil weighs about 75 pounds or less.

16. The heat exchanger coil array of claim 15, wherein at least one heat exchanger coil of the at least six heat exchanger coils weighs about 40 pounds or less.

17. A method for assembling a heat exchanger coil array comprising: providing at least six heat exchanger coils for use with an HVAC&R system for regulating a temperature of a structure, wherein each heat exchanger coil is a separate and independent unit; moving each heat exchanger coil within a passageway adjacent to the HVAC&R system, the passageway having a width along at least a portion of the passageway of about 44 inches; positioning each heat exchanger coil inside of an air handler without removing a door of an access panel of the air handler; and connecting each heat exchanger coil to receive fluid from a fluid source of the system, the fluid connection between each heat exchanger coil and the system being separate and independent.

18. The method of claim 17, wherein the width along at least a portion of the passageway is about 36 inches.

19. The method of claim 17, wherein each heat exchanger coil has an individual operating capacity between 10% and 20% of an overall operating capacity of the heat exchanger coil array.

20. The method of claim 17, wherein at least one heat exchanger coil of the at least two heat exchanger coils weighs about 75 pounds or less.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0006] FIG. 1 shows an embodiment for a heating, ventilation, air conditioning, and refrigeration (HVAC&R) system, in accordance with an aspect of the present disclosure;

[0007] FIG. 2 shows an embodiment of a compressor unit of an HVAC&R system, in accordance with an aspect of the present disclosure;

[0008] FIG. 3 schematically illustrates an embodiment of an HVAC&R system, in accordance with an aspect of the present disclosure;

[0009] FIGS. 4-6 show different orthogonal views of a ventilation system, in accordance with an aspect of the present disclosure;

[0010] FIG. 7 shows a condenser coil array of region 7 taken from FIG. 4, in accordance with an aspect of the present disclosure; and

[0011] FIG. 8 shows the condenser coil array of FIG. 4 with a replacement component, in accordance with an aspect of the present disclosure.

DETAILED DESCRIPTION

[0012] FIG. 1 shows an environment for an HVAC&R system 10 in a structure or building 12 for a typical commercial setting. System 10 may include a compressor (not shown) incorporated into a chiller 16 that can supply a chilled liquid that may be used to cool building 12. In one embodiment, compressor 38 may be a screw compressor 38 (see for example, FIG. 2). In other embodiments, compressor 38 may be a centrifugal compressor, scroll compressor, or reciprocal compressor (not shown). System 10 includes an air distribution system that circulates air through building 12. The air distribution system can include an outside air duct 19, exhaust air duct 21, air return duct 20, an air supply duct 18, and an air handler 22. Air handler 22 can include a heat exchanger (not shown) that is connected to a boiler (not shown) and chiller 16 by conduits or chilled water pipes 24. Air handler 22 may receive either heated liquid from the boiler or chilled liquid from chiller 16, depending on the mode of operation of HVAC&R system 10. HVAC&R system 10 is shown with a separate air handler on each floor of building 12, but it will be appreciated that these components may be shared between or among floors. In another embodiment, the system 10 may include an air-cooled chiller that employs an air-cooled heat exchanger coil or heat exchanger coil array as a condenser, as will be discussed in additional detail below. In another embodiment, a heat exchanger coil or heat exchanger coil array can operate as an evaporator. An air-cooled chiller may be located on the exterior of the building (e.g., adjacent to or on the roof of the building). Another embodiment is a packaged roof top unit (RTU) that combines an air cooled chiller and an air handler.

[0013] FIG. 2 shows an embodiment of a screw compressor in a packaged unit for use with chiller 16. The packaged unit includes a screw compressor 38, a motor 43 to drive screw compressor 38, a control panel 50 to provide control instructions to equipment included in the packaged unit, such as motor 43. An oil separator 46 can be provided to remove entrained oil (used to lubricate the rotors of screw compressor 38) from the discharge vapor before providing the discharge vapor to its intended application.

[0014] FIG. 3 shows an HVAC&R or liquid chiller system 10, which includes compressor 38, condenser 26, water chiller or evaporator 42, and a control panel 50. Control panel 50 may include a microprocessor 70, an interface board 72, an analog-to-digital (A to D) converter 74, and/or a non-volatile memory 76. Control panel 50 may be positioned or disposed locally and/or remotely to system 10. Control panel 50 receives input signals from system 10. For example, temperature and pressure measurements may indicate the performance of system 10. The signals may be transmitted to components of system 10, for example, a compressor capacity control signal, to control the operation of system 10. In some embodiments, the liquid chiller or HVAC&R system 10 may include other features that are not shown in FIG. 3. While the following description of system 10 is in terms of a liquid chiller system, it is to be understood that the invention could be applied to any HVAC&R system.

[0015] As shown in the illustrated embodiment of FIG. 3, the compressor 38 may compress a refrigerant vapor and deliver the refrigerant vapor to the condenser 26 through a discharge conduit 68. Compressor 38 may be any suitable type of compressor including screw compressor, reciprocating compressor, scroll compressor, rotary compressor, or another type of compressor. In some embodiments, the system 10 may have more than one compressor 38 and/or one or more refrigerant circuits.

[0016] The refrigerant vapor delivered to the condenser 26 may enter into a heat exchange relationship with a fluid (e.g., air or water) and undergo a phase change to a refrigerant liquid as a result of the heat exchange relationship with the fluid. For example, the refrigerant vapor in the condenser 26 enters into the heat exchange relationship with the fluid, which may flow through a heat exchanger coil 52 connected to a cooling tower 54. In other embodiments, the refrigerant vapor may be condensed in the coil 52, which may be in a heat exchange relationship with air flowing across an external surface of the coil 52. In any case, the refrigerant vapor in condenser 26 undergoes a phase change to a refrigerant liquid as a result of the heat exchange relationship with the water or air. Accordingly, the condensed liquid refrigerant from the condenser 26 may flow to the evaporator 42.

[0017] Evaporator 42 may include a heat exchanger coil 62 having a supply line 56 and a return line 58 connected to a cooling load 60. Heat exchanger coil 62 can include a plurality of tube bundles within the evaporator 42. A secondary liquid (e.g., water, ethylene, calcium chloride brine, sodium chloride brine, or any other suitable secondary liquid) may travel into the evaporator 42 via return line 58 and exit the evaporator 42 via supply line 56. The liquid refrigerant in the evaporator 42 enters into a heat exchange relationship with the secondary liquid in heat exchanger coil 62 to chill the temperature of the secondary liquid in heat exchanger coil 62. The refrigerant liquid in evaporator 42 may then undergo a phase change to the refrigerant vapor as a result of the heat exchange relationship with the secondary liquid in heat exchanger coil 62. The vapor refrigerant in the evaporator 42 may exit evaporator 42 and return to the compressor 38 by a suction line to complete the cycle. While system 10 has been described in terms of the condenser 26 and the evaporator 42, any suitable configuration of heat exchangers may be used in the system 10, provided that the appropriate phase change of the refrigerant is obtained.

[0018] In one embodiment, chiller system capacity may be controlled by adjusting the speed of a compressor motor driving compressor 38, using a variable speed drive (VSD). Additionally, the HVAC&R system 10 may include one or more heat pumps in addition to, or in lieu of, the refrigeration cycles.

[0019] To drive the compressor 38, the system 10 may include a motor or drive mechanism 66 for the compressor 38. While the term motor is used with respect to the drive mechanism for the compressor 38, the term motor is not limited to a motor, but may encompass any component that may be used in conjunction with providing the driving force for the compressor 38, such as a variable speed drive and a motor starter. Motor or drive mechanism 66 may be an electric motor and associated components. Other drive mechanisms, such as steam turbines, gas turbines, steam engines, or gas engines and associated components may be used to drive the compressor 38.

[0020] The control panel 50 may be configured to execute a control system that uses a control algorithm or multiple control algorithms (e.g., software) to control operation of the system 10. Additionally, the control panel 50 may be configured to determine and implement an operating configuration for the inverters of a VSD (not shown) to control the capacity of the compressor 38 (or multiple compressors) in response to a particular output capacity set point of the system 10. The control algorithm or multiple control algorithms may be computer programs or software stored in non-volatile memory 76 of the control panel 50 and may include a series of instructions executable by the microprocessor 70. The control algorithm may be embodied in a computer program or multiple computer programs and may be executed by the microprocessor 70. Additionally or alternatively, the control algorithm may be implemented and executed using digital and/or analog hardware (not shown). If hardware is used to execute the control algorithm, the corresponding configuration of the control panel 50 may be changed to incorporate any additional components and/or to remove any components that may be superfluous.

[0021] The chiller system 10, as illustrated in FIG. 3, includes the compressor 38 in fluid communication with an oil separator 46. An oil and refrigerant gas mixture travels along discharge pipe 64 from the compressor 38 to the oil separator 46. The compressor 38 may be in fluid communication with the oil separator 46 via an oil return line 109. The condenser 26 may also be in fluid communication with the oil separator 46, and refrigerant gas travels from the oil separator 46 to the condenser 26. As discussed above, the condenser 26 may cool and condense refrigerant vapor into refrigerant liquid, which is in turn may be directed to the evaporator 42 through an expansion valve 61. Heat transfer may then occur between the refrigerant liquid and a second fluid that is cooled by the refrigerant liquid to provide desired refrigeration. The refrigerant liquid in evaporator 42 is converted into the refrigerant vapor by absorbing heat from the chilled liquid. The refrigerant vapor from the evaporator 42 may then return to the compressor 38. This refrigeration cycle repeats as a continuous cycle when the chiller system is in operation.

[0022] FIGS. 4-6 show an embodiment of a self contained cooling system with ventilation system 80 for the HVAC&R system 10. Ventilation system 80 includes a structure commonly referred to as an air handler or rooftop air handling unit or a packaged rooftop unit 30, which typically is positioned on an upper surface of the building 12. Accordingly, the temperature of the building 12 may be maintained by the HVAC&R system 10 (and the ventilation system 80). As further shown in FIGS. 4-6, the rooftop unit 30 receives outside air 82 and return air 84 from a return air opening 85. A portion of the return air 84 may be mixed with the outside air 82 to form mixed air 86. The mixed air 86 may be filtered by a filter 81 and brought into thermal contact with cooling coils 88, which may reduce the temperature and the amount of water vapor entrained in the mixed air 86, to generate supply air 90. The supply air 90 may then be directed by a fan 89 through an opening 94 into the building 12. A portion of the return air 84 may be directed by another fan 83 through an opening 78 to generate the exhaust air 87.

[0023] As further shown in FIGS. 5 and 6, the rooftop unit 30 (FIG. 4) may include the condenser 26, which may have fans 27 for drawing outside air 82 into thermal heat exchange with condenser coils 28. The outside air 82 may then cool the refrigerant vapor flowing through the condenser coils 28 heated air 92 may be discharged from the condenser 26.

[0024] As discussed above, typical heat exchanger coil arrays that may be utilized in evaporators or condensers of HVAC&R systems are bulky, heavy, expensive, and difficult to install. For example, an air handler rated at or having an operating capacity of 46,000 cubic feet per minute (CFM) may include multiple heat exchanger coils that each weigh more than 300 pounds and each have a length of approximately 120 inches and a height of approximately 40 inches. There are numerous disadvantages associated with conventional heat exchanger coils of such large size. Office buildings compliant with building codes (e.g., codes regulated by the Life Safety Code of the National Fire Protection Association) provide that for new construction, aisles or passageways near an exit should have at least 44 inches of clear space (width). However, in some cases a width of 36 inches may be acceptable if fewer than 50 people would be using the exit. For an existing building, it may be permissible to have aisles or passageways (e.g., not near an exit) as narrow as 28 inches wide.

[0025] Clearly, such constrained access within a building is insufficient for manipulating large objects, such as typical heat exchanger coils. That is, moving typical heat exchanger coils within a passageway of the structure to/from the air handler having a width along at least a portion of the passageway of about 44 inches, about 36 inches, or about 28 inches may be problematic. Additionally, a passageway adjacent to the HVAC&R system 10 within the building 12 may also have a limited width of about (e.g., within 5% of or within 10% of) 44 inches, about 36 inches, or about 28 inches. For example, a space between the air handler 22 and a wall of the building 12 may include the limited width, such that a coil pull may be included to insert and/or remove typical heat exchanger coils. Reducing a size of the heat exchanger coils may enable insertion and/or removal of the heat exchanger coils without including the coil pull in the HVAC&R system 10. Of course, an assembled heat exchanger coil array that includes a plurality of typical heat exchanger coils is also difficult to move within a passageway of the structure to/from the air handler. As a result, equipment such as a crane or carts may be used to install and/or replace typical heat exchanger coils. Further, when the air handler is positioned within the building 12 (e.g., the air handler 22) a portion of the exterior of the building 12 (e.g., windows) may be removed to permit access inside of the building because the typical heat exchanger coils may be too large to maneuver within entrances, aisles, or passageways of the building 12. Moreover, rooms containing the air handlers may be sufficiently sized to accommodate removal of typical heat exchanger coils from the air handler (e.g., 12-15 feet of clearance).

[0026] Further, air handlers may include a coil pull (e.g., dead space) to facilitate removal of large heat exchanger coils from the air handler. For example, equipment such as forklifts or other machinery may be utilized to remove large heat exchanger coils from the air handler due to the large size and weight of the coils. Therefore, the coil pull may be included to accommodate such equipment and facilitate the removal of the coils. Additionally, the air handler may include an access panel that provides access to the heat exchanger coils. In some cases, a door (e.g., panel) of the access panel may be removed to enable large heat exchanger coils to be removed from the air handler. For example, large heat exchanger coils may not fit through an opening of the access panel when the door is fixed to a wall and/or component of the air handler. Thus, the door is removed so that the large heat exchanger coils may be removed and/or replaced.

[0027] There are further disadvantages associated with typical heat exchanger coils of such large size. For example, should one heat exchanger coil fail, capacity of the air handler may be reduced by between 10 percent and 33 percent, between 15 percent and 50 percent, or between 75 and 100 percent (e.g., when the failed heat exchanger coil is removed from the air handler and a replacement component, such as a blank or blank-off, cannot be inserted in place of the heat exchanger coil). In addition, typical, large heat exchanger coils may have long lead times (e.g., a time between ordering and delivery of the heat exchanger coil). Furthermore, cleaning of typical heat exchanger coils may be performed while the typical heat exchanger coils are installed in the air handler thereby causing the air handler to shut down for cleaning.

[0028] Accordingly, the illustrated embodiment of FIG. 7, taken from region 7 of FIG. 4, shows an enhanced arrangement of a condenser coil array or heat exchanger coil array 132, which for purposes of this disclosure, may also be interchangeably referred to as a condenser heat exchanger coil array or the like. As shown in the illustrated embodiment of FIG. 7, the heat exchanger coil array 132 includes twenty (20) heat exchanger coils 134a-134t. In other embodiments, the heat exchanger coil array 132 may include any suitable number of heat exchanger coils 134. For example, the heat exchanger coil array 132 may include less than 20 heat exchanger coils 134. In other embodiments, the heat exchanger coil array 132 may include more than 20 heat exchanger coils 134. In still further embodiments, the heat exchanger coil array 132 may include at least six heat exchanger coils 134, at least eight heat exchanger coils 134, at least ten heat exchanger coils 134, at least twelve heat exchanger coils, or at least twenty heat exchanger coils 134. Additionally, each of the heat exchanger coils 134 may include a same size. In other embodiments, at least one of the heat exchanger coils 134 may be sized differently from the other heat exchanger coils 134.

[0029] In any case, each of heat exchanger coils 134a-134t is a separate and independent component that can be installed and/or removed independently of the other heat exchanger coils. Accordingly, each of the heat exchanger coils 134a-134t may operate in a parallel arrangement with one another. In such embodiments, the fluid flow through each of the heat exchanger coils 134a-134t may be individually controlled (e.g., via the control panel 50), controlled at a single point (e.g., via the control panel 50), or controlled as subgroups of the heat exchange coils 134a-134t (e.g., via the control panel 50). For example, as shown in the illustrated embodiment of FIG. 7, the heat exchanger coil array 132 may be coupled to a header 135 that is coupled to individual inlets 137a-137t (and/or outlets) of each of the heat exchanger coils 134a-134t. The header 135 may be coupled to the control panel 50, such that individual operation of each of the heat exchanger coils 134a-134t may be controlled as the control panel 50 directs fluid to one or more of each of the heat exchanger coils 134a-134t. However, in other embodiments, the heat exchanger coils 134a-134t may operate in a series arrangement with one another. As shown in the illustrated embodiment of FIG. 7, the heat exchanger coil array 132 that is included in an air handler rated at or having an operating capacity of 46,000 CFM, each heat exchanger coil 134a-134t may weigh approximately (e.g., within 5%, within 10%, or within 15% of) 40 pounds and has a length of approximately (e.g., within 5%, within 10%, or within 15% of) 30 inches and a height of approximately (e.g., within 5%, within 10%, or within 15% of) 24 inches.

[0030] Additionally, each heat exchanger coil may include a design operating capacity of approximately (e.g., within 5%, within 10%, or within 15% of) 2,300 CFM at a flow rate of approximately (e.g., within 5%, within 10%, or within 15% of) 460 FPM (feet per minute). For example, in some embodiments, each heat exchanger coil 134 has an operating capacity between about 1,500 CFM and 2,500 CFM, between about 1,700 CFM and 2,300 CFM, between about 1,900 CMF and 2,100 CFM, about 2,500 CFM, about 2,400 CFM, about 2,300 CFM, about 2,200 CFM, about 2,100 CFM, about 2,000 CFM, about 1,900 CFM, about 1,800 CFM, about 1,700 CFM, about 1,600 CFM, about 1,500 CFM, or any range or sub-range thereof. In other embodiments, none of the heat exchanger coils 134 may include a design air flow of greater than 6,000 CFM. As used herein, design air flow of an individual heat exchanger coil 134 is the maximum airflow of the air handler divided by the total surface area of all of the heat exchanger coils 134 multiplied by the surface area of the individual heat exchanger coil 134. Additionally, in some embodiments, the flow rate of air may be between 100 FPM and 1000 FPM, between 250 FPM and 500 FPM, between 300 FPM and 500 FPM, approximately 350 FPM, approximately 400 FPM, approximately 425 FPM, approximately 450 FPM, or approximately 500 FPM.

[0031] In some embodiments, a capacity of each of the heat exchanger coils 134a-134t may be based on the overall operating capacity of the air handler. For example, in some embodiments, the capacity of each heat exchanger coil 134 may be between 1% and 45% of the overall capacity of the air handler, between 2% and 30% of the overall capacity of the air handler, between 5% and 25% of the overall capacity of the air handler, between 10% and 20% of the overall capacity of the air handler, approximately (e.g., within 5%, within 10%, or within 15% of) 3% of the overall capacity of the air handler, approximately 5% of the overall capacity of the air handler, approximately 10% of the overall capacity of the air handler, approximately 15% of the overall capacity of the air handler, or approximately 17% of the overall capacity of the air handler.

[0032] Embodiments of the present disclosure provide for a heat exchanger coil array 132 that includes heat exchanger coils 134 that are reduced in size when compared to individual heat exchanger coils in typical heat exchanger coil arrays. For example, in some embodiments, the heat exchanger coils 134 may weigh about 75 pounds or less, about 70 pounds or less, about 65 pounds or less, about 60 pounds or less, about 55 pounds or less, about 50 pounds or less, about 45 pounds or less, about 40 pounds or less, about 35 pounds or less, about 30 pounds or less, about 25 pounds or less, or any suitable value between 75 pounds and about 25 pounds thereof. Utilizing heat exchanger coils that are about 75 pounds or less facilitates installation and replacement of the heat exchanger coils 134 (e.g., installation and/or replacement may be performed by one or two people). It should be understood that the heat exchanger coils 134 of the present disclosure may include any combination of length and width dimensions that enable the heat exchanger coils 134 to move within a threshold passageway width (e.g., 28 inches) for a given structure. Additionally, the heat exchanger coils 134 may have any combination of operating capacity and/or weight that enable the heat exchanger coils 134 to move within the threshold passageway width (e.g., 28 inches) for a given structure.

[0033] In other words, the heat exchanger coils 134a-134t may include a reduced size when compared to typical heat exchangers that include large, heavy coils. The reduced size of the heat exchanger coils 134a-134t may enable the heat exchanger coils 134a-134t to be maneuvered through entrances, aisles, or passageways of the building 12. Further, the reduced size may enable the heat exchanger coils 134a-134t to be removed from the air handler without using equipment, such as a forklift or other machinery. Therefore, the coil pull of the air handler may be eliminated from the air handler, which may enable the overall size of the air handler to be reduced. Further still, the reduced size of the heat exchanger coils 134a-134t may facilitate removal and/or replacement of the heat exchanger coils 134a-134t because the heat exchanger coils 134a-134t may fit through the access panel of the air handler without removing the door of the access panel.

[0034] As discussed above, in some embodiments, each of the heat exchanger coils 134a-134t may be independently connected to receive a fluid from a fluid source of the HVAC&R system 10. For example, each of the heat exchanger coils 134 may have a single point connection with the air handler (e.g., each of the heat exchanger coils 134 includes piping or plumbing that enables the heat exchanger coil 134 to be readily incorporated into the air handler). As shown in the illustrated embodiment of FIG. 8, the heat exchanger coil 134d (FIG. 7) may be removed and replaced by a replacement component 136d, such as a replacement heat exchanger coil, a blank, or blank-off. The replacement heat exchanger coil, the blank, or the blank-off may thereby permit the air handler to continue to operate. As a result of the heat exchanger coils 134 being independently connectable to the air handler, each heat exchanger coil 134 may be individually removed without significantly reducing the operating capacity of the air handler. For example, for the heat exchanger coil array 132 (FIG. 7), replacing one of the heat exchanger coils 134a-134t with appropriately sized replacement component (e.g., a blank or blank-off) the loss of operating capacity may be less than 10 percent.

[0035] While only certain features and embodiments of the invention have been shown and described, many modifications and changes may occur to those skilled in the art (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters (e.g., temperatures, pressures, etc.), mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited in the claims. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. Furthermore, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation may not have been described (i.e., those unrelated to the presently contemplated best mode of carrying out the invention, or those unrelated to enabling the claimed invention). It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation.