Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
COMBINATION PHASE SEPARATOR AND DRIER FOR A REFRIGERATION APPLIANCE
Document Type and Number:
WIPO Patent Application WO/2015/077150
Kind Code:
A1
Abstract:
A device is provided for a refrigeration system that separates liquid and vapor phases of the refrigerant while also drying the liquid phase to remove water. The phase separator and drier are provided integrally as part of the same device (222). The device (222) can be used with e.g., dual evaporator refrigeration systems and both single and multicomponent refrigerants. Improved efficiencies in space and plumbing so as to reduce costs can be achieved.

Inventors:
JUNGE BRENT ALDEN (US)
Application Number:
PCT/US2014/065701
Publication Date:
May 28, 2015
Filing Date:
November 14, 2014
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
GEN ELECTRIC (US)
International Classes:
F25B5/02; F25D11/02; F25B1/10; F25B5/04; F25B40/06; F25B43/00
Foreign References:
US20120137724A12012-06-07
US20060168996A12006-08-03
US3019614A1962-02-06
JP2002349978A2002-12-04
Other References:
None
Attorney, Agent or Firm:
ZHANG, Douglas, D. et al. (Global Patent Operation3135 Easton Turnpik, Fairfield CT, US)
Download PDF:
Claims:
WHAT IS CLAIMED IS:

1. A dual evaporator refrigeration appliance, comprising: a refrigerant for circulation within a refrigeration system of the appliance; a compressor for providing a pressurized flow of the refrigerant; a condenser configured to receive and cool the flow of pressurized refrigerant provided by the compressor; a first reducing device configured to receive the flow of refrigerant from the condenser and configured for reducing the pressure of the refrigerant stream; a phase separating and drying device configured for receipt of the refrigerant stream provided by the first reducing device, the phase separating and drying device comprising a chamber having a top, middle, and a bottom along a vertical direction; an inflow line in fluid communication with the first reducing device, the inflow line having at least one opening positioned for releasing refrigerant into the chamber; a vapor outflow line positioned near the top of the chamber and configured for receiving vapor refrigerant from the chamber; a liquid outflow line positioned near the bottom of the chamber and configured for receiving liquid refrigerant from the chamber; a drying element configured to remove water from liquid refrigerant provided by the inflow line; a first evaporator configured to receive and evaporate refrigerant provided by the vapor outflow line of the phase separating and drying device; and a second evaporator configured to receive and evaporate refrigerant provided by the liquid outflow line of the phase separating and drying device.

2. The dual evaporator refrigeration appliance of claim 1, wherein the drying element comprises a desiccant.

3. The dual evaporator refrigeration appliance of claim 2, further comprising a filter positioned in the chamber and configured for filtering liquid refrigerant provided to the liquid outflow.

4. The dual evaporator refrigeration appliance of claim 3, wherein the filter comprises a screen.

5. The dual evaporator refrigeration appliance of claim 4, further comprising a perforated metal element positioned over the desiccant, wherein the filter is located below the desiccant so that liquid refrigerant flows through the perforated metal element, desiccant, and then the filter before exiting the chamber through the liquid outflow line.

6. The dual evaporator refrigeration appliance of claim 1, further comprising a second reducing device configured to receive vapor refrigerant from the vapor outflow line of the phase separating and drying device, wherein the first evaporator is configured to receive refrigerant from the second reducing device.

7. The dual evaporator refrigeration appliance of claim 1, further comprising a junction for combining vaporized refrigerant from the first evaporator and the second evaporator into a combined refrigerant stream for delivery to the compressor.

8. The dual evaporator refrigeration appliance of claim 7, further comprising a heat exchanger configured for exchanging heat between the combined refrigerant stream and refrigerant supplied to the phase separating and drying device from the condenser.

9. A dual evaporator refrigeration appliance, comprising: a zeotropic refrigerant for circulation within a refrigeration system of the appliance; a compressor for providing a pressurized flow of the refrigerant; a condenser configured to receive and cool the flow of pressurized refrigerant, the condenser comprising a phase separating and drying device for separating the flow of pressurized refrigerant into a first refrigerant stream and a second refrigerant stream, wherein the phase separating and drying device comprises a chamber having a top and a bottom along a vertical direction; an inflow line in receipt of the flow of refrigerant, the inflow line having at least one opening positioned for releasing the refrigerant into the chamber; a vapor outflow line positioned near the top of the chamber and configured for receiving vapor refrigerant from the chamber and providing such refrigerant to the first refrigerant stream; a liquid outflow line positioned near the bottom of the chamber and configured for receiving liquid refrigerant from the chamber and providing such refrigerant to the second refrigerant stream; a drying element configured to remove water from liquid refrigerant provided by the inflow line; a first expansion device in receipt of the first refrigerant stream from the condenser and configured for reducing the pressure of the first refrigerant stream; and a second expansion device in receipt of the second refrigerant stream from the condenser and configured for reducing the pressure of the second refrigerant stream; a first evaporator configured to receive and evaporate at least a portion of the first refrigerant stream; and a second evaporator configured to receive and evaporate at least a portion of the second refrigerant stream.

10. The dual evaporator refrigeration appliance of claim 9, further comprising: a junction that joins the first refrigerant stream from the first evaporator and the second refrigerant stream from the second expansion device into a combined refrigerant stream; and wherein the second evaporator is configured to receive and evaporate at least a portion of the combined refrigerant stream and provide an inlet refrigerant flow to the compressor.

11. The dual evaporator refrigeration appliance of claim 10, wherein the first and second expansion devices are in thermal communication with the inlet refrigerant stream to the compressor so as to cool the first refrigerant stream and the second refrigerant stream.

12. The dual evaporator refrigeration appliance of claim 11, wherein the first expansion device and the second expansion device each comprise a capillary tube.

13. The dual evaporator refrigeration appliance of claim 12, wherein the pressure of the first refrigerant stream is substantially equal to the pressure of the second refrigerant stream.

14. The dual evaporator refrigeration appliance of claim 10, wherein the zeotropic refrigerant comprises two or more refrigerants selected from a group consisting of an R-134a refrigerant, an R-245fa refrigerant, an R-245ca refrigerant, an R-1234yf refrigerant, an R-600a refrigerant, pentane, butane, and propane.

15. The dual evaporator refrigeration appliance of claim 10, wherein the drying element comprises a desiccant.

16. The dual evaporator refrigeration appliance of claim 15, further comprising a filter positioned in the chamber and configured for filtering liquid refrigerant provided to the liquid outflow.

17. The dual evaporator refrigeration appliance of claim 16, wherein the filter comprises a screen.

18. The dual evaporator refrigeration appliance of claim 17, further comprising a perforated metal element positioned above the desiccant, wherein the filter is located below the desiccant so that liquid refrigerant flows through the perforated metal element, the desiccant, and then the filter before exiting the chamber through the liquid outflow line.

19. A dual evaporator refrigeration appliance, comprising: a refrigerant for circulation within a refrigeration system of the appliance; a phase separating and drying device configured for receipt of a stream of the refrigerant that includes liquid refrigerant and a vapor refrigerant, the phase separating and drying device comprising a chamber having a top, middle, and a bottom along a vertical direction; an inflow line for receipt of the stream of refrigerant, the inflow line having at least one opening positioned for releasing the stream of refrigerant into the chamber; a vapor outflow line positioned near the top of the chamber and configured for receiving vapor refrigerant from the chamber; a liquid outflow line positioned near the bottom of the chamber and configured for receiving liquid refrigerant from the chamber; and a drying element configured to remove water from liquid refrigerant provided by the inflow line.

Description:
COMBINATION PHASE SEPARATOR AND DRIER FOR A REFRIGERATION

APPLIANCE

FIELD OF THE INVENTION

[0001] The subject matter of the present disclosure relates generally to a device for separating the vapor and liquid phases of a refrigerant flow and for drying the liquid phase.

BACKGROUND OF THE INVENTION

[0002] Conventional refrigerator appliances commonly utilize a single evaporator, fan, and damper to move cooled air from the frozen food compartment containing the evaporator to the fresh food compartment. The position of the damper can be controlled depending upon whether cooling of the fresh food compartment is needed. One or more temperature sensors are utilized to measure temperature in one or more of the compartments.

[0003] Refrigeration systems that use dual evaporators can be useful for removing heat from two different locations. For example, in a refrigerator appliance, a refrigeration loop can be provided that uses one evaporator to remove heat from the fresh food compartment and another evaporator to remove heat from the frozen food compartment. Such dual evaporator systems can be useful in e.g., avoiding temperature and/or humidity gradients that can occur with single evaporator systems.

[0004] Dual evaporator refrigeration systems can be costly and more complex than single evaporator refrigeration systems. Dual evaporator refrigeration systems can also incur cycling losses when switching operation from the fresh food evaporator to the freezer evaporator. Evaporators in such existing systems are also known to be relatively large, which can impact the energy efficiency of the appliance in which the refrigeration system resides. Some dual evaporator systems also utilize dual compressors, which further increases energy usage and inefficiency. A dual evaporator system that can use a single compressor could provide e.g., savings in costs and efficiency. Such a system can require e.g., a device to separate different phases of the refrigerant. [0005] When a refrigeration system is charged, small amounts of water - i.e. moisture - may be inadvertently introduced. The presence of water in the refrigeration system is deleterious to operation. A drier can be used to remove moisture from the refrigerant. Providing such drier as a separate component adds cost to the refrigeration system and consumes space in the machinery compartment that, for a refrigerator appliance, is already crowded and needed for other components. Accordingly, a drier than can be provided as part of another component of the refrigeration system would be useful. Such a drier that can be incorporated as part of another component such as a phase separating device in a dual evaporator system would be particularly beneficial.

BRIEF DESCRIPTION OF THE INVENTION

[0006] The present invention provides a device for a refrigeration system that separates liquid and vapor phases of the refrigerant while also drying the liquid phase to remove water. The phase separator and drier are provided integrally as part of the same device. Such device can be used with e.g., dual evaporator refrigeration systems and both single and multi-component refrigerants such as zeotropic refrigerants. Improved efficiencies in space and plumbing so as to reduce costs can be achieved. Additional aspects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention.

[0007] In one exemplary embodiment, the present invention provides a dual evaporator refrigeration appliance. The appliance includes a refrigerant for circulation within a refrigeration system of the appliance; a compressor for providing a pressurized flow of the refrigerant; a condenser configured to receive and cool the flow of pressurized refrigerant provided by the compressor; a first reducing device configured to receive the flow of refrigerant from the condenser and configured for reducing the pressure of the refrigerant stream; and a phase separating and drying device configured for receipt of the refrigerant stream provided by the first reducing device.

[0008] The phase separating and drying device includes a chamber having a top, middle, and a bottom along a vertical direction; an inflow line in fluid communication with the first reducing device, the inflow line having at least one opening positioned for releasing refrigerant into the chamber; a vapor outflow line positioned near the top of the chamber and configured for receiving vapor refrigerant from the chamber; a liquid outflow line positioned near the bottom of the chamber and configured for receiving liquid refrigerant from the chamber; and a drying element configured to remove water from liquid refrigerant provided by the inflow line.

[0009] A first evaporator is configured to receive and evaporate refrigerant provided by the vapor outflow of the phase separating and drying device. A second evaporator is configured to receive and evaporate refrigerant provided by the liquid outflow line of the phase separating and drying device.

[0010] In another exemplary embodiment, the present invention provides a dual evaporator refrigeration appliance. The appliance includes a zeotropic refrigerant for circulation within a refrigeration system of the appliance. A compressor provides a pressurized flow of the refrigerant. A condenser is configured to receive and cool the flow of pressurized refrigerant and includes a phase separating and drying device for separating the flow of pressurized refrigerant into a first refrigerant stream and a second refrigerant stream.

[0011] The phase separating and drying device includes a chamber having a top and a bottom along a vertical direction; an inflow line in receipt of the flow of refrigerant, the inflow line having at least one opening positioned for releasing the refrigerant into the chamber; a vapor outflow line positioned near the top of the chamber and configured for receiving vapor refrigerant from the chamber and providing such refrigerant to the first refrigerant stream; a liquid outflow line positioned near the bottom of the chamber and configured for receiving liquid refrigerant from the chamber and providing such refrigerant to the second refrigerant stream; and a drying element configured to remove water from liquid refrigerant provided by the inflow line.

[0012] A first expansion device is in receipt of the first refrigerant stream from the condenser and is configured for reducing the pressure of the first refrigerant stream. A second expansion device is in receipt of the second refrigerant stream from the condenser and is configured for reducing the pressure of the second refrigerant stream. A first evaporator is configured to receive and evaporate at least a portion of the first refrigerant stream. A second evaporator is configured to receive and evaporate at least a portion of the second refrigerant stream.

[0013] In another exemplary embodiment, the present invention provides a dual evaporator refrigeration appliance that includes a refrigerant for circulation within a refrigeration system of the appliance and a phase separating and drying device configured for receipt of a stream of the refrigerant that includes liquid refrigerant and a vapor refrigerant. The phase separating and drying device includes a chamber having a top, middle, and a bottom along a vertical direction; an inflow line for receipt of the stream of refrigerant, the inflow line having at least one opening positioned for releasing the stream of refrigerant into the chamber; a vapor outflow line positioned near the top of the chamber and configured for receiving vapor refrigerant from the chamber; a liquid outflow line positioned near the bottom of the chamber and configured for receiving liquid refrigerant from the chamber; and a drying element configured to remove water from liquid refrigerant provided by the inflow line.

[0014] These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:

[0016] FIG. 1 provides a front view of an exemplary embodiment of a refrigerator appliance.

[0017] FIG. 2 is a schematic view of an exemplary embodiment of a refrigeration system as may be used in the exemplary refrigerator appliance of FIG. 1.

[0018] FIG. 3 is a close-up schematic view of an exemplary embodiment of a phase separating and drying device of the present invention as may be used in the refrigeration systems of FIG. 2, FIG. 4, and/or others. [0019] FIG. 4 is a schematic view of another exemplary embodiment of a refrigeration system as may be used in the exemplary refrigerator appliance of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

[0020] Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

[0021] FIG. 1 provides a front view of a representative refrigerator 10 in an exemplary embodiment of the present invention. More specifically, for illustrative purposes, the present invention is described with a refrigerator 10 having a construction as shown and described further below. As used herein, "refrigerator" includes appliances such as a refrigerator/freezer combination, side -by-side, bottom mount, compact, and any other style or model of a refrigerator. Accordingly, other configurations including multiple and different styled compartments could be used with refrigerator 10, it being understood that the configuration shown in FIG. 1 is by way of example only. Additionally, the refrigeration system of the present invention is not limited to a refrigerator appliance and can be used in other applications where dual evaporators are desirable as well such as e.g., where separate cooling at two or more locations is desired.

[0022] Refrigerator 10 includes a fresh food (FF) storage compartment 12 and a freezer (FZ) storage compartment 14. Freezer compartment 14 and fresh food compartment 12 are arranged side-by- side within an outer case 16 and defined by inner liners 18 and 20 therein. A space between case 16 and liners 18 and 20, and between liners 18 and 20, is filled with foamed-in-place insulation. Outer case 16 normally is formed by folding a sheet of a suitable material, such as pre-painted steel, into an inverted U-shape to form the top and side walls of case 16. A bottom wall of case 16 normally is formed separately and attached to the case side walls and to a bottom frame that provides support for refrigerator 10. Inner liners 18 and 20 are molded from a suitable plastic material to form freezer compartment 14 and fresh food compartment 12, respectively. Alternatively, liners 18, 20 may be formed by bending and welding a sheet of a suitable metal, such as steel.

[0023] A breaker strip 22 extends between a case front flange and outer front edges of liners 18, 20. Breaker strip 22 is formed from a suitable resilient material, such as an extruded acrylo-butadiene-styrene based material (commonly referred to as ABS). The insulation in the space between liners 18, 20 is covered by another strip of suitable resilient material, which also commonly is referred to as a mullion 24. In one embodiment, mullion 24 is formed of an extruded ABS material. Breaker strip 22 and mullion 24 form a front face, and extend completely around inner peripheral edges of case 16 and vertically between liners 18, 20. Mullion 24, insulation between compartments, and a spaced wall of liners separating compartments, sometimes are collectively referred to herein as a center mullion wall 26. In addition, refrigerator 10 includes shelves 28 and slide-out storage drawers 30, sometimes referred to as storage pans, which normally are provided in fresh food compartment 12 to support items being stored therein.

[0024] Refrigerator 10 can be operated by one or more controllers (not shown) or other processing devices according to programming and/or user preference via manipulation of a control interface 32 mounted e.g., in an upper region of fresh food storage compartment 12 and connected with the controller. The controller may include one or more memory devices and one or more microprocessors, such as a general or special purpose microprocessor operable to execute programming instructions or micro-control code associated with the operation of the refrigerator. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH. In one embodiment, the processor executes programming instructions stored in memory. The memory may be a separate component from the processor or may be included onboard within the processor. As used herein, "controller" includes the singular and plural forms.

[0025] The controller may be positioned in a variety of locations throughout refrigerator 10. In the illustrated embodiment, the controller may be located e.g., behind an interface panel 32 or doors 42 or 44. Input/output ("I/O") signals may be routed between the control system and e.g., temperature sensors 52 and 54 as well as various operational components of refrigerator 10. These signals can be provided along wiring harnesses that may be routed through e.g., the back, sides, or mullion 24. Typically, through user interface panel 32, a user may select various operational features and modes and monitor the operation of refrigerator 10. In one embodiment, the user interface panel may represent a general purpose I/O ("GPIO") device or functional block. In one embodiment, the user interface panel 32 may include input components, such as one or more of a variety of electrical, mechanical or electromechanical input devices including rotary dials, push buttons, and touch pads. The user interface panel 32 may include a display component, such as a digital or analog display device designed to provide operational feedback to a user. The user interface panel may be in communication with the controller via one or more signal lines or shared communication busses.

[0026] A shelf 34 and wire baskets 36 are also provided in freezer compartment 14. In addition, an ice maker 38 may be provided in freezer compartment 14. A freezer door 42 and a fresh food door 44 close access openings to freezer and fresh food compartments 14, 12, respectively. Each door 42, 44 is mounted to rotate about its outer vertical edge between an open position, as shown in FIG. 1, and a closed position (not shown) closing the associated storage compartment. Freezer door 42 includes a plurality of storage shelves 46, and fresh food door 44 includes a plurality of storage shelves 48.

[0027] Refrigerator 10 includes a machinery compartment that incorporates at least part of a refrigeration cycle - exemplary embodiments of which are depicted in each of FIGS. 2 and 4. Refrigeration systems 200, 300 each include a first evaporator 212, 312 and a second evaporator 214, 314. By way of example, first evaporator 212 or 312 can be used to a cool frozen food (FZ) compartment 14 and second evaporator 214 or 314 can be used to a cool fresh food (FF) compartment 12. A fan 216 or 316 can be used to circulate air in compartment 14 over first evaporator 212 or 312. Similarly, a fan 218 or 318 can be used to circulate air in compartment 12 over second evaporator 214 or 314. Alternatively, refrigeration systems 200 and 300 can be used in other appliances where e.g., evaporators 212, 312 and 214, 314 are positioned in different locations at which cooling to different temperatures is desired.

[0028] Referring now to the exemplary embodiment of FIG. 2, refrigeration system 200 includes a circulating refrigerant such as e.g., R-12, R-22, R-134a and R- 600a. While certain older refrigerants are being phased out and replaced by environmentally-friendlier compounds, it is to be understood that the principles of the invention are not limited to any particular refrigerant.

[0029] As shown in FIG. 2, the circulating refrigerant enters a compressor 202 in a thermodynamic state known as a "superheated vapor" and is compressed to a higher pressure in compressor 202, resulting in a higher temperature as well. This relatively hot, compressed vapor exiting the compressor 202 is still in a thermodynamic state known as a "superheated vapor," but it is now at a temperature and pressure at which it can be condensed with cooling water or cooling air from e.g., ambient conditions. Thus, this flow (or stream) of hot vapor refrigerant 248 is routed through a condenser 204 configured to receive the pressurized refrigerant provided by compressor 202.

[0030] In condenser 204, refrigerant flow 248 is cooled and condensed into a liquid flow by flowing through a coil or tubes with relatively cooler water or cooler air flowing across such coil or tubes of condenser 204 to receive heat from the refrigerant. By way of example, such relatively cooler air may typically be air in a room or structure in which refrigerator 10 operates. Fan 270 can be used to provide a flow of such air. Thus, using condenser 204, the circulating refrigerant rejects heat from refrigeration system 200 to e.g., water, air or other heat transfer medium.

[0031] A first reducing device 206 (also referred to as a first reducer or first expansion device) is configured to receive a flow of cooled, liquid refrigerant 221 from condenser 204. More particularly, the resulting condensed liquid refrigerant flow 221 from condenser 204, now in a thermodynamic state known as a "saturated liquid," flows to first reducing device 206. In one exemplary embodiment, first reducing device 206 may be a capillary tube. Therein, the circulated refrigerant undergoes an abrupt reduction in pressure that typically results in the evaporation of a part of the liquid refrigerant flow 221. Such evaporation generally lowers the temperature of the liquid and vapor refrigerant mixture to a temperature relatively colder than the temperature of the enclosed compartment 12 or 14 to be refrigerated. [0032] A phase separating and drying device 222 is configured to receive the flow 223 of liquid and vapor refrigerant mixture from first reducing device 206. In phase separating and drying device 222, the refrigerant mixture is separated into two phases, i.e., liquid and vapor, and the liquid phase is dried as more fully described below. An optional, second reducing device 210 (e.g., another capillary tube; also referred to as a second expansion device) is configured to receive the predominantly vapor flow 224 from device 222. After a further reduction in pressure by device 210, a refrigerant flow 230 is provided to first evaporator 212 for vaporization to cool freezer compartment 14 of refrigerator 10. At the same, the predominantly liquid flow 234 of the refrigerant output from device 222 flows to the second evaporator 214 for vaporization to cool fresh food compartment 12 of refrigerator 10.

[0033] For compartment 12 , a fan 218 circulates relatively warmer air in the enclosed compartment across the coil or tubes of evaporator 214 that carries relatively colder refrigerant liquid and vapor mixture. Similarly, for compartment 14, a fan 216 circulates relatively warmer air in the enclosed compartment across the coil or tubes of evaporator 212 that carries relatively colder refrigerant liquid and vapor mixture. Temperature in each compartment 12 and 14 can be monitored by a temperature sensor (not shown).

[0034] Flows 232 and 235 of saturated refrigerant vapor from each evaporator 212 and 214 are combined using a junction or combing device 220. This combined flow 239 then flows back to compressor 202. The refrigerant may become superheated while exchanging heat with refrigerant in the first reducing device 206 through heat exchanger 207. From compressor 202, the cycle is repeated as previously described.

[0035] FIG. 3 provides a schematic view of an exemplary embodiment of a phase separating and drying device 222 or 322 as may be used in the exemplary refrigeration systems of e.g., FIG. 2, FIG. 4 and/or others. As shown, device 222 is configured for receipt of a refrigerant flow or stream 223 having a combination of liquid and vapor refrigerant. Refrigerant flow 223 may be a single component or may contain multiple components such as a zeotropic refrigerant. For this exemplary embodiment, refrigerant flow 223 is released into a chamber 256 of device 222 at a location that is about at the center 227 along vertical direction V. More particularly, device 222 has an inflow line 243 in fluid communication with first reducing device 206 and supplies refrigerant flow 223 into chamber 256 though an opening 244. As shown, opening 244 is positioned for releasing refrigerant flow 223 at about the center 227 along vertical direction V of device 222. Other locations may be used as well.

[0036] Phase separating and drying device 222 also include a vapor outflow line 247 positioned through top 229 of chamber 256. Vapor outflow line 247 is configured for receiving refrigerant in its vapor phase from chamber 256 through an opening 246 positioned near top 229 of chamber 256. Vapor outflow line 247 provides refrigerant flow 224. Device 222 also includes a liquid outflow line 225 positioned near bottom 231 of chamber 256 and configured for receiving refrigerant in its liquid phase from chamber 256. Liquid outflow line 225 provides refrigerant flow 234.

[0037] Device 222 includes a drying element 236 that is configured to remove water from the liquid phase refrigerant L released from opening 244. For example, drying element 236 could be a desiccant that removes water from liquid phase L. Other materials or elements could be used as well. For this exemplary embodiment, device 222 also includes a pair of perforated metal screen 238 and 240 that traps drying element 236 therebetween.

[0038] Additionally, device 222 is equipped with a filter 242 positioned at bottom 231. Filter 242 is configured to remove contaminants such as sediment, particles, or other materials in the liquid phase refrigerant L that could e.g., damage compressor 202 or foul other components of refrigeration system 200. For example, filter 242 could be configured as a mesh or screen with small openings that block the flow of contaminants while allowing the flow of refrigerant.

[0039] FIG. 4 depicts another exemplary embodiment of a refrigeration system 300 that can be used in e.g., refrigerator appliance 10. Refrigeration system 300 is charged with a zeotropic refrigerant mixture, which is a mixture of two or more refrigerants that have different saturated liquid temperatures at the same pressure. Consequently, the concentrations of the individual refrigerants between the liquid and vapor phases are typically different when the refrigerant mixture is vaporized or boiled. In addition, zeotropic refrigerant mixtures typically exhibit temperature glide - meaning that the saturated liquid temperature of the zeotropic refrigerant changes as the relative compositions of refrigerants in the liquid mixture changes during vaporization.

[0040] Examples of non-flammable refrigerants that can be used in a zeotropic mixture include, but are not limited, to R-134a, R245fa, R245ca and small amounts of R-600, R-600a or R-1234yf. Examples of refrigerants that may be used in a zeotropic mixture with low Global Warming Potential (GWP) include R-600, R-600a, pentane, R290 and R-1234yf. Different mixture percentages of such refrigerants can be used in the dual evaporator refrigerant system 300 as well. In one embodiment, the zeotropic refrigerant includes two or more refrigerants selected from a group consisting of an R-134a refrigerant, an R-245fa refrigerant, an R-245ca refrigerant, an R-1234yf refrigerant, an R-600a refrigerant, pentane, butane, and propane.

[0041] Compressor 302 receives an inlet refrigerant flow 339 (i.e. of the zeotropic refrigerant) and provides for a flow 348 of pressurized refrigerant to condenser 304. Flow 348 and flow 339 are both in the form of a superheated vapor. However, the pressure of the superheated vapor in flow 348 is much higher than flow 339 and can be condensed at least partially into liquid in condenser 304.

[0042] In one embodiment, the refrigerant mixture exiting compressor 302 in flow 348 can be about 30% R-134a and about 70% R-600a (i.e., a percent ratio of 30/70), at a temperature of about 117 degrees (Fahrenheit) and a pressure of about 114 psia. R-134a has a higher vapor saturation temperature than R-600a, i.e., the temperature at which R-134a refrigerant changes from a gas back to a liquid is higher than the temperature at which R-600a changes from a gas back to a liquid when subject to the same pressure.

[0043] In condenser 304, the pressurized flow from compressor 302 is cooled by e.g., exchanging heat with the environment of refrigeration system 300. For example, in the case of refrigerator 10, condenser 304 may exchange heat with ambient air from the room in which refrigerator 10 is located. Fan 370 may be used to flow air over e.g., coils, fins, and/or other elements making up condenser 304.

[0044] The zeotropic refrigerant mixture is separated and dried in condenser 304 by a phase separating and drying device 322, which is similar in construction and operation to phase separating and drying device 222 shown in FIG. 3. The phase separating and drying device 322 separates the refrigerant mixture into what becomes a first refrigerant stream 324 and a second refrigerant stream 334, and dries refrigerant 334 stream by removing water therefrom. Stream 324 is initially provided from device 322 as a vapor stream while stream 334 is initially provided from device 222 as a liquid stream. Each stream 324 and 334 has a different composition of the zeotropic refrigerant mixture. For example, if the zeotropic refrigerant mixture includes a mixture of R-134A and R-600a, refrigerant stream 324 could have a different ratio of R-134a to R-600a than refrigerant stream 334.

[0045] Phase separating and drying device 322 can be configured with its chamber 356 positioned at a location in the flow of refrigerant through condenser 304 where the refrigerant is part condensed liquid and part uncondensed vapor. Thus, phase separating and drying device 322 is located between the inlet 316 and the outlet 317 of condenser 304 and likely at a location between the midpoint 319 and inlet 316 of the refrigerant flow through condenser 304. Phase separating and drying device 322 therefore divides condenser 304 into a first portion 308a and a second portion 308b.

[0046] Phase separating and drying device 322 is configured so the velocity of refrigerant passing through allows a liquid layer to form at the bottom 331 of chamber 356 due to the force of gravity and a vapor rises to the top 329. The vapor in phase separating and drying device 322 continues into the second portion 308b of condenser 304 where it becomes a liquid having more of the lower vapor saturation temperature refrigerant (e.g., R-600a) that exits as first refrigerant stream 324. The liquid stream 334 from device 322 has more of the higher vapor saturation temperature refrigerant (e.g., R-134a) and exits condenser 304 as second refrigerant stream 334.

[0047] By way of example, where the zeotropic refrigerant mixture is R-134a and R-600a, second refrigerant stream 334 exits device 322 of condenser 304 at about 44.5% R-134a and about 55.5% R-600a (i.e., a percent ratio of 44.5/55.5), at a temperature of about 105 degrees (Fahrenheit) and a pressure of about 114 psia. First refrigerant stream 324 exits condenser 304 at about 15.5% R-134a and about 84.5% R-600a (i.e., a percent ratio of 15.5/84.5) at a temperature of about 94 degrees (Fahrenheit) and a pressure of about 114 psia. [0048] First expansion device 310 receives first refrigerant stream 324 from condenser 304. First expansion device 310 is configured to reduce the pressure of first refrigerant stream 324. Similarly, second expansion device 306 is configured to reduce the pressure of second refrigerant stream 334. In one exemplary embodiment of the present invention, expansion device 310 and/or 306 include a capillary tube as will be understood by one of skill in the art using the teachings disclosed herein. Other expansion devices may be used as well.

[0049] Continuing with FIG. 4, for this exemplary embodiment, first evaporator 312 receives first refrigerant flow or stream 330 from first expansion device 310 and operates to evaporate at least a portion of stream 330. This evaporation process provides cooling that can be used to e.g., remove heat from frozen food (FZ) compartment 14. A junction 320 joins first refrigerant stream 332 from first evaporator 312 and second refrigerant stream 335 from second expansion device 306 to create a combined refrigerant stream 337. Because streams 332 and 335 are at substantially the same pressure, these streams can be joined at junction 320 without necessarily using special devices such as a valve or venturi.

[0050] Second evaporator 314 receives and evaporates at least a portion of the combined refrigerant stream 337 and provides the same as an inlet refrigerant flow 339 to compressor 302. The evaporation of combined refrigerant stream 337 in second evaporator 314 provides cooling that can be used to e.g., remove heat from fresh food (FF) compartment 12.

[0051] As indicated by block 307, first and second expansion devices 306 and 310 are in thermal communication with inlet refrigerant flow 339 to compressor 302 so as to cool first refrigerant stream 324 and second refrigerant stream 334. Block 307 may be e.g., a heat exchanger or a section where tubing making up devices 306, 310 and flows 324, 334 are located near or in contact with one another so as to promote the conduction of heat. Other configurations to exchange heat therebetween may be used as well. Compressor 302 is used to pressurize inlet refrigerant flow 339 from second evaporator 314 and repeat the cycle as previously described.

[0052] In addition to other advantages, the exemplary embodiment of refrigeration system 300 depicted in FIG. 4 can also provide advantages in the layout or construction of plumbing and/or components in a refrigerator appliance such as refrigerator 10.

[0053] It should be noted that the phase separating and drying device of the present invention may be used in a variety of other types of refrigeration systems in addition to those described above.

[0054] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.