THERMAL ENERGY EXCHANGER FOR A HEATING, VENTILATING, AND AIR CONDITIONING SYSTEM

FIELD OF THE INVENTION

The invention relates to a climate control system for a vehicle and more particularly to a thermal energy exchanger for a heating, ventilating, and air conditioning system.

BACKGROUND OF THE INVENTION

A vehicle typically includes a climate control system which maintains a temperature within a passenger compartment of the vehicle at a comfortable level by providing heating, cooling, and ventilation. Comfort is maintained in the passenger compartment by an integrated mechanism referred to in the art as a heating, ventilating and air conditioning (HVAC) system. The HVAC system conditions air flowing therethrough and distributes the conditioned air throughout the passenger compartment.

Typically, a compressor of a refrigeration system provides a flow of a fluid having a desired temperature to an evaporator disposed in the HVAC system to condition the air. The compressor is generally driven by a fuel-powered engine of the vehicle. However, in recent years, vehicles having improved fuel economy over the fuel-powered engine and other vehicles are quickly becoming more popular as a cost of traditional fuel increases. The improved fuel economy is due to known technologies such as regenerative braking, electric motor assist, and engine-off operation. Although the technologies improve fuel economy, accessories powered by the fuel-powered engine no longer operate when the fuel-powered engine is not in operation. One major accessory that does not operate is the compressor of the refrigeration system. Therefore, without the use of the compressor, the evaporator disposed in the HVAC system does not condition the air flowing therethrough and the temperature of the passenger compartment increases to a point above a desired temperature.

Accordingly, vehicle manufacturers have used a thermal energy exchanger disposed in the HVAC system to condition the air flowing therethrough when the fuel-powered engine is not in operation. One such thermal energy exchanger, also referred to as a cold accumulator, is described in U.S. Pat. No. 6,854,513 entitled VEHICLE AIR CONDITIONING SYSTEM WITH COLD ACCUMULATOR, hereby incorporated herein by reference in its entirety. The cold accumulator includes a phase change material, also referred to as a cold accumulating material, disposed therein. The cold accumulating material absorbs heat from the air when the fuel-powered engine is not in operation. The cold accumulating material is then recharged by the conditioned air flowing from the cooling heat exchanger when the fuel-powered engine is in operation.

In U.S. Pat. No. 6,691,527 entitled AIR-CONDITIONER FOR A MOTOR VEHICLE, hereby incorporated herein by reference in its entirety, a thermal energy exchanger is disclosed having a phase change material disposed therein. The phase change material of the thermal energy exchanger conditions a flow of air through the HVAC system when the fuel-powered engine of the vehicle is not in operation. The phase change material is charged by a flow of a fluid from the refrigeration system therethrough.

While the prior art HVAC systems perform adequately, it is desirable to produce a thermal energy exchanger having a phase change material disposed therein for an HVAC system, wherein an effectiveness and efficiency thereof are maximized.

SUMMARY OF THE INVENTION

In concordance and agreement with the present invention, a thermal energy exchanger having a phase change material disposed therein for an HVAC system, wherein an effectiveness and efficiency thereof are maximized, has surprisingly been discovered.

In one embodiment, the thermal energy exchanger for a heating, ventilating, and air conditioning system comprises a main housing having a hollow interior; a plurality of tubes disposed in the hollow interior of the housing; and a phase change material disposed in the tubes, wherein the phase change material is at least one of encapsulated with a thermally conductive material and impregnated with a thermally conductive material.

In another embodiment, the thermal energy exchanger for a heating, ventilating, and air conditioning system comprises a hollow main housing including a first inlet and a first outlet, wherein the first inlet and the first outlet are in fluid communication with a source of cooled fluid, the housing further including a second inlet and a second outlet, wherein the second inlet and the second outlet are in fluid communication with a heat exchanger disposed in a control module of a heating, ventilating, and air conditioning system, and wherein each of the inlets and the outlets perform as a diffuser; a plurality of tubes disposed in the housing forming open areas therebetween, wherein at least one of the tubes is adapted to receive one of a fluid from the source of cooled fluid and a fluid from the heat exchanger therethrough; and a phase change material disposed in the open areas of the housing.

In another embodiment, the thermal energy exchanger for a heating, ventilating, and air conditioning system comprises a main housing having a hollow interior; a fluid disposed in the housing, the fluid adapted to circulate through a conduit to a heat exchanger disposed in an HVAC module of a heating, ventilating, and air conditioning system; and a phase change material disposed in the fluid, wherein the phase change material is at least one of encapsulated with a thermally conductive material and impregnated with a thermally conductive material.

BRIEF DESCRIPTION OF THE DRAWINGS

The above, as well as other objects and advantages of the invention, will become readily apparent to those skilled in the art from reading the following detailed description of various embodiments of the invention when considered in the light of the accompanying drawings in which:

FIG. 1 is a schematic flow diagram of an HVAC system including a fragmentary sectional view of an HVAC module having a thermal energy exchanger disposed therein according to an embodiment of the invention;

FIG. 2 is a fragmentary cross-sectional view of the thermal energy exchanger illustrated in FIG. 1, wherein the thermal energy exchanger includes a phase change material impregnated with a thermally conductive material;

FIG. 3 is a schematic flow diagram of the HVAC system illustrated in FIG. 1, wherein the thermal energy exchanger is in fluid communication with a source of cooled fluid;

FIG. 4 is a fragmentary cross-sectional view of the thermal energy exchanger illustrated in FIG. 3, wherein the thermal energy exchanger includes an encapsulated phase change material;

FIG. 5 is a fragmentary cross-sectional view of the thermal energy exchanger illustrated in FIG. 3, wherein the thermal energy exchanger includes an encapsulated phase change material impregnated with a thermally conductive material;

FIG. 6 is a schematic flow diagram of an HVAC system including a cross-sectional view of a thermal energy exchanger having a phase change material disposed therein according to another embodiment of the invention;

FIG. 7 is an enlarged sectional view of the phase change material disposed in the thermal energy exchanger illustrated in FIG. 6 within circle 7, wherein the phase change material is encapsulated;

FIG. 8 is an enlarged sectional view of the phase change material disposed in the thermal energy exchanger illustrated in FIG. 6 within circle 8, wherein the phase change material having a thermally conductive material disposed therein is encapsulated;

FIG. 9 is a schematic flow diagram of an HVAC system including a cross-sectional view of a thermal energy exchanger having a phase change material disposed therein according to another embodiment of the invention;

FIG. 10 a schematic flow diagram of the HVAC system illustrated in FIG. 9, wherein the thermal energy exchanger includes interleaved tubes;

FIG. 11 a schematic flow diagram of an HVAC system including a cross-sectional view of a thermal energy exchanger having a phase change material disposed therein according to another embodiment of the invention;

FIG. 12 is an enlarged sectional view of the phase change material disposed in the thermal energy exchanger illustrated in FIG. 11 within circle 12, wherein the phase change material is encapsulated; and

FIG. 13 is an enlarged sectional view of the phase change material disposed in the thermal energy exchanger illustrated in FIG. 11 within circle 13, wherein the phase change material having a thermally conductive material disposed therein is encapsulated.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The following detailed description and appended drawings describe and illustrate various exemplary embodiments of the invention. The description and drawings serve to enable one skilled in the art to make and use the invention, and are not intended to limit the scope of the invention in any manner.

FIGS. 1 and 3 show a heating, ventilating, and air conditioning (HVAC) system 10 according to an embodiment of the invention. The HVAC system 10 typically provides heating, ventilation, and air conditioning for a passenger compartment of a vehicle (not shown) The HVAC system 10 includes a control module 12 to control at least a temperature of the passenger compartment.

The module 12 illustrated includes a hollow main housing 14 with an air flow conduit 15 formed therein. The housing 14 includes an inlet section 16, a mixing and conditioning section 18, and an outlet and distribution section (not shown). In the embodiment shown, an air inlet 22 is formed in the inlet section 16. The air inlet 22 is in fluid communication with a supply of air (not shown). The supply of air can be provided from outside of the vehicle, recirculated from the passenger compartment of the vehicle, or a mixture of the two, for example. The inlet section 16 is adapted to receive a blower wheel (not shown) therein to cause air to flow through the air inlet 22. A filter (not shown) can be provided upstream or downstream of the inlet section 16 if desired.

The mixing and conditioning section 18 of the housing 14 is adapted to receive an evaporator core 24, a thermal energy exchanger 26, and a heater core 28 therein. In the embodiment shown, the thermal energy exchanger 26 and the heater core 28 are disposed downstream of a blend door 29. The blend door 29 is adapted to selectively permit a flow of air through the thermal energy exchanger 26 and the heater core 28 when the HVAC system 10 is not operating in a pull-down mode. A filter (not shown) can also be provided upstream of the evaporator core 24, if desired. The evaporator core 24 is in fluid communication with a source of cooled fluid 30 such as a refrigeration system, for example, through a conduit 36. The source of cooled fluid 30 includes a fluid 37, shown in FIGS. 4 and 5, circulating therein. The fluid 37 absorbs thermal energy and conditions the air flowing through the HVAC module 12.

As illustrated in FIGS. 2, 4, and 5, the thermal energy exchanger 26 is a louvered-fin heat exchanger. It is understood that the thermal energy exchanger 26 can be any conventional thermal energy exchanger as desired. The thermal energy exchanger 26 is adapted to absorb thermal energy and cool the air flowing therethrough when a fuel-powered engine of the vehicle is not in operation. As shown, the thermal energy exchanger 26 includes a plurality of tubes 46 with louvered fins 48 formed thereon. Each of the fins 48 abuts an outer surface of the tubes 46 for enhancing thermal energy transfer of the thermal energy exchanger 26. The fins 48 include a plurality of crests 50 formed thereon. The crests 50 are formed substantially parallel to each other and at a substantially 90 degree angle to the tubes 46. It is understood that the crests 50 can be formed at any angle to the tubes 46 if desired. Each of the crests 50 define an air space 52 extending between the tubes 46 and the fins 48.

The tubes 46 include a phase change material 56 disposed therein. The phase change material 56 is any material that melts and solidifies at certain temperatures and is capable of storing and releasing thermal energy such as a paraffin wax, an alcohol, water, and any combination thereof, for example. As illustrated in FIGS. 2 and 5, the phase change material 56 can be impregnated with a thermally conductive material 58 to further enhance the transfer of thermal energy. It is understood that the thermally conductive material 58 can be any conventional material such as a graphite powder, for example. The phase change material 56 is adapted to absorb thermal energy from the air flowing through the thermal energy exchanger 26 when the fuel-powered engine is not in operation. Accordingly, when the fuel-powered engine of the vehicle is in operation, the phase change material 56 is adapted to release thermal energy into conditioned air from the evaporator 24 flowing therethrough.

As illustrated in FIG. 3, the thermal energy exchanger 26 can also be in fluid communication with the source of cooled fluid 30 through a conduit 38. A valve 39 can be disposed in the conduit 38 to militate against a flow of the fluid 37 therethrough. The thermal energy exchanger 26 is adapted to absorb thermal energy and cool the air flowing therethrough when a fuel-powered engine of the vehicle is not in operation. The thermal energy exchanger 26 is adapted to receive the fluid 37 from the source of cooled fluid 30 therethrough. As shown in FIGS. 4 and 5, the phase change material 56 can be encapsulated in a thermally conductive casing 60a, or coated with a thermally conductive coating 60b. The casing 60a and the coating 60b can be produced from any conventional material such as a polyethylene, for example. In the embodiment shown, the casing 60a and the coating 60b permit the phase change material 56 to be disposed in the fluid 37 circulating through the tubes 46 of the thermal energy exchanger 26. The encapsulated phase change material 56 is adapted to absorb thermal energy from the air flowing through the thermal energy exchanger 26 when the fuel-powered engine is not in operation, and release thermal energy into the fluid 37 when the fuel-powered engine is in operation.

As illustrated in FIG. 5, the tubes 46 of the thermal energy exchanger 26 can further include a plurality of internal fins 66 formed on an inner surface thereof, and a plurality of screens 68 disposed therein. The internal fins 66 are adapted to further enhance the transfer of thermal energy of the thermal energy exchanger 26. The screens 68 are disposed in an inlet 70 and an outlet 72 of each of the tubes 46 and extend across an inner diameter thereof. The screens 68 are adapted to permit the flow of the fluid 37 therethrough while militating against the flow of the encapsulated phase change material 56 from the thermal energy exchanger 26. As shown, the encapsulated phase change material 56 can include the thermally conductive material 58 disposed therein.

The heater core 28 and a source of heated fluid 74 are fluidly connected by a conduit 76. The source of heated fluid 74 can be any conventional source of heated fluid such as the fuel-powered engine of the vehicle, for example, and the heated fluid can be any conventional fluid such as an engine coolant, for example. A valve 75 can be disposed in the conduit 76 to selectively militate against a flow of heated fluid therethrough. The heater core 28 is adapted to release thermal energy and heat the air flowing therethrough when the fuel-powered engine of the vehicle is in operation.

In operation, the HVAC system 10 conditions air by heating or cooling the air, and providing the conditioned air to the passenger compartment of the vehicle. Air flows through the housing 14 of the module 12. Air from the supply of air is received in the inlet section 16 of the housing 14 in the air inlet 22.

When the fuel-powered engine of the vehicle is in operation, the fluid 37 from the source of cooled fluid 30 circulates through the conduit 36. Accordingly, the fluid 37 circulates through the evaporator core 24, as shown in FIG. 1. The air from the inlet section 16 flows into the evaporator core 24 where the air is cooled to a desired temperature by a transfer of thermal energy from the air to the fluid 37 from the source of cooled fluid 30. The conditioned air stream then exits the evaporator core 24. When the HVAC system 10 is not operating in the pull-down mode, the air from the evaporator core 24 is selectively permitted by the blend door 29 to flow into the thermal energy exchanger 26.

In the thermal energy exchanger 26, the conditioned air flows through the air spaces 52 defined by the louvered fins 48 and the tubes 46 of the thermal energy exchanger 26. The conditioned air absorbs thermal energy from the phase change material 56 disposed in the tubes 46. The transfer of thermal energy from the phase change material 56 to the conditioned air cools and solidifies the phase change material 56. It is understood that the fluid 37 from the source of cooled fluid 30 can also circulate through the conduit 38 and the thermal energy exchanger 26, as shown in FIG. 3. The fluid 37 flows from the source of cooled fluid 30 through the tubes 46 to absorb thermal energy from the phase change material 56 disposed therein. Accordingly, the transfer of thermal energy to the fluid 37 further cools and solidifies the phase change material 56.

When the fuel-powered engine of the vehicle is not in operation, the fluid 37 from the source of cooled fluid 30 does not circulate through the conduits 36, 38. Accordingly, the fluid 37 does not circulate through the evaporator core 24 or the thermal energy exchanger 26. The air from the inlet section 16 flows into and through the evaporator core 24 where a temperature thereof is unchanged. The air stream then exits the evaporator core 24 and is selectively permitted by the blend door 29 to flow into the thermal energy exchanger 29.

In the thermal energy exchanger 26, the air flows through the air spaces 52 defined by the louvered fins 48 and the tubes 46 of the thermal energy exchanger 26. The air is cooled to a desired temperature by a transfer of thermal energy from the phase change material 56 disposed therein to the air. Accordingly, the phase change material 56 is caused to melt. The conditioned cooled air then exits the thermal energy exchanger 26 and flows through the heater core 28, which is not in operation, and into the outlet and distribution section.

FIG. 6 shows an HVAC system according to another embodiment of the invention. Reference numerals for similar structure in respect of the description of FIGS. 1 thru 5 are repeated in FIGS. 6 thru 8 with a prime (′) symbol. An HVAC system 10′ includes a control module 12′ to control at least a temperature of the passenger compartment. The module 12′ illustrated includes a hollow main housing 14′ with an air flow conduit 15′ formed therein. The housing 14′ includes an inlet section 16′, a mixing and conditioning section 18′, and an outlet and distribution section (not shown). In the embodiment shown, an air inlet 22′ is formed in the inlet section 16′. The air inlet 22′ is in fluid communication with a supply of air (not shown). The supply of air can be provided from outside of the vehicle, recirculated from the passenger compartment of the vehicle, or a mixture of the two, for example. The inlet section 16′ is adapted to receive a blower wheel (not shown) therein to cause air to flow through the air inlet 22′. A filter (not shown) can also be provided upstream or downstream of the inlet section 16′ if desired.

The mixing and conditioning section 18′ of the housing 14′ is adapted to receive an evaporator core 24′, and at least one of a heat exchanger 80 and a heater core 28′ therein. In the embodiment shown, the heat exchanger 80 and the heater core 28′ are disposed downstream of a blend door 29′. The blend door 29′ is adapted to selectively permit a flow of air through the heat exchanger 80 and the heater core 28′ when the HVAC system 10′ is not operating in a pull-down mode. A filter (not shown) can be provided upstream of the evaporator core 24′, if desired.

The evaporator core 24′ is in fluid communication with a source of cooled fluid 30′ such as a refrigeration system, for example, through a conduit 36′. The evaporator core 24′ is adapted to absorb thermal energy and cool the air flowing therethrough when a fuel-powered engine of the vehicle is in operation. The heat exchanger 80 is in fluid communication with a thermal energy exchanger 82 through a conduit 84. The conduit 84 includes a pump 88 adapted to cause a fluid 90 disposed therein to circulate. It is understood that the fluid 90 can be any conventional fluid such as a coolant, for example. The fluid 90 is adapted to absorb thermal energy and cool the air flowing through the heat exchanger 80 when a fuel-powered engine of the vehicle is not in operation. The thermal energy exchanger 82 is also in fluid communication with the source of cooled fluid 30′ through a conduit 86. The conduit 86 can include a valve 87 disposed therein to selectively militate against a flow of the fluid 37′ therethrough. In the embodiment shown, the heater core 28′ is in fluid communication with a source of heated fluid 74′ through a conduit 76′. The source of heated fluid 74′ can be any conventional source of heated fluid such as the fuel-powered engine of the vehicle, for example, and the heated fluid can be any conventional fluid such as an engine coolant, for example. A valve 75′ can be disposed in the conduit 76′ to selectively militate against a flow of heated fluid therethrough. It is understood that the heat exchanger 80 can be in fluid communication with the source of heated fluid 74′ as desired without departing from the scope and spirit of the invention.

In the embodiment shown, the thermal energy exchanger 82 includes a main housing 92 having a hollow interior. The main housing 92 may be made of conventional materials such as polypropylene, for example. In the embodiment shown, the main housing 92 is generally rectangular in shape. It is understood that the main housing 92 can have other shapes as desired. The main housing 92 includes a first inlet 94, a second inlet 96, a first outlet 98, and a second outlet 100 formed thereon. The inlets 94, 96 and the outlets 98, 100 are formed to extend laterally outwardly from the main housing 92. The first inlet 94 and the first outlet 98 are in fluid communication with the source of cooled fluid 30′ through the conduit 86. The second inlet 96 and the second outlet 100 are in fluid communication with the heat exchanger 80 through the conduit 84. The inlets 94, 96 and the outlets 98, 100 each perform as a diffuser to decrease a flow velocity of the respective fluids 37′, 90 circulated therethrough. An insulating material 102 can be disposed on an outer surface of the main housing 92 to militate against a dissipation of thermal energy therefrom.

The first inlet 94 and the first outlet 98 are fluidly connected by a plurality of tubes 104. The tubes 104 are disposed in the hollow interior of the thermal energy exchanger 82 and are adapted to receive the fluid 37′ therethrough. The tubes 104 include a plurality of spaced apart fins 106 extending radially outwardly therefrom. The fins 106 enhance a transfer of thermal energy between the fluids 37′, 90. The tubes 104 and the fins 106 are produced from a thermally conductive material such as copper, for example. The tubes 104 are substantially parallel in relation to each other and are spaced apart to define a series of open areas 108 therebetween. The open areas 108 permit a flow of the fluid 90 therethrough.

The fluid 90 includes a phase change material 56′ disposed therein. The phase change material 56′ is any material that melts and solidifies at certain temperatures and is capable of storing and releasing thermal energy such as a paraffin wax, an alcohol, water, and any combination thereof, for example. As shown in FIGS. 7 and 8, the phase change material 56′ is encapsulated in a thermally conductive casing 60a′, or coated with a thermally conductive coating 60b′. The casing 60a′ and the coating 60b′ can be produced from any conventional material such as a polyethylene, for example. The casing 60a′ and the coating 60b′ permit the phase change material 56′ to be disposed in the fluid 90 circulating through the open areas 108. The encapsulated phase change material 56′ is adapted to absorb thermal energy of the fluid 90 flowing through the heat exchanger 80 when the fuel-powered engine is not in operation, and release thermal energy into the fluid 37′ when the fuel-powered engine is in operation. As illustrated in FIG. 8, the encapsulated phase change material 56′ can include a thermally conductive material 58′ disposed therein to further enhance the transfer of thermal energy, if desired.

The second inlet 96 and the second outlet 100 are fluidly connected by the open areas 108. As shown, each of the second inlet 96 and the second outlet 100 can include a screen 110 extending across a diameter thereof. The screen 110 is adapted to permit the flow of the fluid 90 therethrough, while militating against the flow of the encapsulated phase change material 56′ from the thermal energy exchanger 82. It is understood that the first inlet 94 and the first outlet 98 can be fluidly connected by open areas and the second inlet 96 and the second outlet 100 fluid connected by tubes, if desired.

In use, when the fuel-powered engine of the vehicle is in operation, the fluid 37′ from the source of cooled fluid 30′ circulates through the conduits 36′, 86. Accordingly, the fluid 37′ circulates through the evaporator core 24′ and the thermal energy exchanger 82. The air from the inlet section 16′ flows into the evaporator core 24′ where the air is cooled to a desired temperature by a transfer of thermal energy from the air to the fluid 37′ from the source of cooled fluid 30′. The conditioned air stream then exits the evaporator core 24′. When the HVAC system 10′ is not operating in the pull-down mode, the air from the evaporator core 24′ is selectively permitted by the blend door 29′ to flow through the heat exchanger 80 and the heater core 28′, which is not in operation, and into the outlet and distribution section. The fluid 37′ circulating through the conduit 86 flows into and through the tubes 104 of the thermal energy exchanger 82. The fluid 37′ absorbs thermal energy from the fluid 90 flowing through the open areas 108 and the phase change material 56′ disposed therein. The transfer of thermal energy cools and solidifies the phase change material 56′.

When the fuel-powered engine of the vehicle is not in operation, the fluid 37′ from the source of cooled fluid 30′ does not circulate through the conduits 36′, 86. Accordingly, the fluid 37′ does not circulate through the evaporator core 24′ or the thermal energy exchanger 82. The pump 88 causes the fluid 90 to circulate through the conduit 84, the thermal energy exchanger 82, and the heat exchanger 80. The air from the inlet section 16′ flows into the evaporator core 24′ where a temperature thereof is unchanged. The air then exits the evaporator core 24′ and is selectively permitted by the blend door 29′ to flow into the heat exchanger 80.

In the heat exchanger 80 the air is cooled to a desired temperature by a transfer of thermal energy from the air to the fluid 90 circulating therethrough. The fluid 90 absorbs and transfers the thermal energy from the air to the phase change material 56′ disposed therein, causing the phase change material 56′ to melt. The conditioned cooled air then exits the heat exchanger 80 and flows through the heater core 28′, which is not in operation, and into the outlet and distribution section.

FIGS. 9 and 10 show an HVAC system according to another embodiment of the invention. Reference numerals for similar structure in respect of the description of FIGS. 1 thru 8 are repeated in FIGS. 9 and 10 with a prime (″) symbol. An HVAC system 10″ includes a control module 12″ to control at least a temperature of the passenger compartment. The module 12″ illustrated includes a hollow main housing 14″ with an air flow conduit 15″ formed therein. The housing 14″ includes an inlet section 16″, a mixing and conditioning section 18″, and an outlet and distribution section (not shown). In the embodiment shown, an air inlet 22″ is formed in the inlet section 16″. The air inlet 22″ is in fluid communication with a supply of air (not shown). The supply of air can be provided from outside of the vehicle, recirculated from the passenger compartment of the vehicle, or a mixture of the two, for example. The inlet section 16″ is adapted to receive a blower wheel (not shown) therein to cause air to flow through the air inlet 22″. A filter (not shown) can be provided upstream or downstream of the inlet section 16″ if desired.

The mixing and conditioning section 18″ of the housing 14″ is adapted to receive an evaporator core 24″, and at least one of a heat exchanger 80″ and a heater core (not shown) therein. In the embodiment shown, the heat exchanger 80″ is disposed downstream of a blend door 29″. The blend door 29″ is adapted to selectively permit a flow of air through the heat exchanger 80″ when the HVAC system 10″ is not operating in a pull-down mode. A filter (not shown) can also be provided upstream of the evaporator core 24″, if desired.

The evaporator core 24″ is in fluid communication with a source of cooled fluid 30″ such as a refrigeration system, for example, through a conduit 36″. The evaporator core 24″ is adapted to absorb thermal energy and cool the air flowing therethrough when a fuel-powered engine of the vehicle is in operation. The heat exchanger 80″ is in fluid communication with a thermal energy exchanger 82″ through a conduit 84″. The conduit 84″ includes a pump 88″ and a valve 89 disposed therein. The pump 88″ is adapted to cause a fluid (not shown) disposed therein to circulate. The valve 89 selectively militates against a flow of the fluid therethrough. It is understood that the fluid can be any conventional fluid such as an engine coolant, for example. The fluid is adapted to absorb thermal energy and cool the air flowing through the heat exchanger 80″ when the fuel-powered engine of the vehicle is not in operation. The thermal energy exchanger 82″ is also in fluid communication with the source of cooled fluid 30″ through a conduit 86″. The conduit 86″ can include a valve 87″ disposed therein to selectively militate against a flow of the fluid therethrough. In the embodiment shown, the heat exchanger 80″ is also in fluid communication with a source of heated fluid 74″ through a conduit 76″. The source of heated fluid 74″ can be any conventional source of heated fluid such as the fuel-powered engine of the vehicle, for example, and the heated fluid can be any conventional fluid such as an engine coolant, for example. A valve 75″ may be disposed in the conduit 76″ to selectively militate against a flow of heated fluid therethrough. The heat exchanger 80″ is adapted to release thermal energy and heat the air flowing therethrough when the fuel-powered engine of the vehicle is in operation. It is understood that the source of heated fluid 74″ can be in fluid communication with a heater core as desired without departing from the scope and spirit of the invention.

In the embodiment shown, the thermal energy exchanger 82″ includes a main housing 92″ having a hollow interior. The main housing 92″ may be made of conventional materials such as polypropylene, for example. In the embodiment shown, the main housing 92″ is generally rectangular in shape. It is understood that the main housing 92″ can have other shapes as desired. The main housing 92″ includes a first inlet 94″, a second inlet 96″, a first outlet 98″, and a second outlet 100″ formed thereon. The inlets 94″, 96″ and the outlets 98″, 100″ are formed to extend laterally outwardly from the main housing 92″. The first inlet 94″ and the first outlet 98″ are in fluid communication with the source of cooled fluid 30″ through the conduit 86″. The second inlet 96″ and the second outlet 100″ are in fluid communication with the heat exchanger 80″ through the conduit 84″. The inlets 94″, 96″ and the outlets 98″, 100″ each perform as a diffuser to decrease a flow velocity of the fluids circulated therethrough. An insulating material 102″ can be disposed on an outer surface of the main housing 92″ to militate against a dissipation of thermal energy therefrom.

The first inlet 94″ and the first outlet 98″ are fluidly connected by a plurality of tubes 104″. The tubes 104″ are disposed in the hollow interior of the thermal energy exchanger 82″ and are adapted to receive the fluid from the source of cooled fluid 30″ therethrough. The tubes 104″ include a plurality of spaced apart fins 106″ extending radially outwardly therefrom. The fins 106″ enhance a transfer of thermal energy between the fluid from the source of cooled fluid 30″ and fluid from the heat exchanger 80′. The tubes 104″ and the fins 106″ are produced from a thermally conductive material such as copper, for example. The tubes 104″ are substantially parallel in relation to each other and are spaced apart to define a series of open areas 108″ therebetween.

As illustrated in FIG. 9 and 10, the second inlet 96″ and the second outlet 100″ can also be fluidly connected by a plurality of tubes 112. The tubes 112 are disposed in the hollow interior of the thermal energy exchanger 82″ and are adapted to receive the fluid from the heat exchanger 80″ therethrough. The tubes 112 include a plurality of spaced apart fins 114 extending radially outwardly therefrom. The fins 114 enhance a transfer of thermal energy between the fluids. The tubes 112 and the fins 114 are produced from a thermally conductive material such as copper, for example. The tubes 112 are substantially parallel in relation to each other and are spaced apart to define a series of open areas 116 therebetween. It is understood that the tubes 112 can be interleaved with the tubes 104″, as shown in FIG. 10, to further enhance the transfer of thermal energy between the fluids, if desired. It is further understood that the tubes 112 can include a plurality of spaced apart fins (not shown) extending radially inwardly and an encapsulated phase change material (not shown) disposed therein, if desired, to further enhance the transfer of thermal energy.

The open areas 116 formed between the tubes 112 are in fluid communication with the open areas 108″ formed between the tubes 104″. The open areas 108″, 116 include a phase change material 56″ disposed therein. The phase change material 56″ is any material that melts and solidifies at certain temperatures and is capable of storing and releasing thermal energy such as a paraffin wax, an alcohol, water, and any combination thereof, for example. In the embodiment shown, the phase change material 56″ is adapted to absorb thermal energy of the fluid flowing through the tubes 112 when the fuel-powered engine is not in operation, and release thermal energy to the fluid flowing through the tubes 108″ when the fuel-powered engine is in operation. As illustrated in FIGS. 9 and 10, the phase change material 56″ can include a thermally conductive material 58″ disposed therein to further enhance the transfer of thermal energy. A pocket of air 118 is disposed inside the interior of the thermal energy exchanger 82″ to permit the phase change material 56″ disposed therein to expand when releasing thermal energy to the fluid from the source of cooled fluid 30″.

In use, when the fuel-powered engine of the vehicle is in operation, the fluid from the source of cooled fluid 30″ circulates through the conduits 36″, 86″. Accordingly, the fluid from the source of cooled fluid 30″ circulates through the evaporator core 24″ and the thermal energy exchanger 82″. The air from the inlet section 16″ flows into the evaporator core 24″ where the air is cooled to a desired temperature by a transfer of thermal energy from the air to the fluid from the source of cooled fluid 30″. The conditioned air stream then exits the evaporator core 24″. When the HVAC system 10″ is not operating in the pull-down mode, the air from the evaporator core 24″ is selectively permitted by the blend door 29″ to flow through the heat exchanger 80″ and into the outlet and distribution section. The fluid circulating through the conduit 86″ flows into and through the tubes 104″ of the thermal energy exchanger 82″. The fluid absorbs thermal energy from the phase change material 56″ disposed in the open areas 108″, 116. The transfer of thermal energy cools and solidifies the phase change material 56″. Additionally, the phase change material 56″ cools the fluid circulating through conduit 84″ and the heat exchanger 80″ by absorbing thermal energy therefrom. The thermal energy absorbed by the phase change material 56″ is then transferred to the fluid from the source of cooled fluid 30″.

When the fuel-powered engine of the vehicle is not in operation, the fluid from the source of cooled fluid 30″ does not circulate through the conduits 36″, 86″. Accordingly, the fluid does not circulate through the evaporator core 24″ or the thermal energy exchanger 82″. The pump 88″ causes the fluid disposed in the heat exchanger 80″ to circulate through the conduit 84″ and the thermal energy exchanger 82″. The fluid flows into and through the tubes 112 of the thermal energy exchanger 82″, releasing thermal energy to the phase change material 56″ disposed in the open areas 108″, 116 thereof. Accordingly, the fluid is cooled by the phase change material 56″. The air from the inlet section 16″ flows into and through the evaporator core 24″ where a temperature thereof is unchanged. The air then exits the evaporator core 24″ and is selectively permitted to flow through the heat exchanger 80″.

In the heat exchanger 80″, the air is cooled to a desired temperature by a transfer of thermal energy from the air to the fluid circulating therethrough. The fluid absorbs and transfers the thermal energy from the air to the phase change material 56″ disposed in the open areas 108″, 116 of the thermal energy exchanger 82″ Thus, the phase change material 56″ is caused to melt. The conditioned cooled air then exits the heat exchanger 80″ and flows into the outlet and distribution section.

FIG. 11 shows an HVAC system according to another embodiment of the invention. Reference numerals for similar structure in respect of the description of FIGS. 1 thru 10 are repeated in FIG. 11 with a prime (′″) symbol. An HVAC system 10′″ includes a control module 12′″ to control at least a temperature of the passenger compartment. The module 12′″ illustrated includes a hollow main housing 14′″ with an air flow conduit 15′″ formed therein. The housing 14′″ includes an inlet section 16′″, a mixing and conditioning section 18′″, and an outlet and distribution section (not shown). In the embodiment shown, an air inlet 22′″ is formed in the inlet section 16′″. The air inlet 22′″ is in fluid communication with a supply of air (not shown). The supply of air can be provided from outside of the vehicle, recirculated from the passenger compartment of the vehicle, or a mixture of the two, for example. The inlet section 16′″ is adapted to receive a blower wheel (not shown) therein to cause air to flow through the air inlet 22′″ A filter (not shown) can be provided upstream or downstream of the inlet section 16′″ if desired.

The mixing and conditioning section 18′″ of the housing 14′″ is adapted to receive an evaporator core 24′″, a heat exchanger 80′″, and a heater core 28′″ therein. In the embodiment shown, the heat exchanger 80′″ and the heater core 28′″ are disposed downstream of a blend door 29′″. The blend door 29′″ is adapted to selectively permit a flow of air through the heat exchanger 80′″ and the heater core 28′″ when the HVAC system 10′″ is not operating in a pull-down mode. A filter (not shown) can be provided upstream of the evaporator core 24′″, if desired. The evaporator core 24′″ is in fluid communication with a source of cooled fluid 30′″ such as a refrigeration system, for example, through a conduit 36′″. The evaporator core 24′″ is adapted to absorb thermal energy and cool the air flowing therethrough when a fuel-powered engine of the vehicle is in operation. The heat exchanger 80′″ is in fluid communication with a thermal energy exchanger 120 through a conduit 84′″. The conduit 84′″ includes a pump 88′″ adapted to cause a fluid 90′″ disposed therein to circulate. It is understood that the fluid 90′″ can be any conventional fluid such as a coolant, for example. The fluid 90″ is adapted to absorb thermal energy and cool the air flowing through the heat exchanger 80′″ when the fuel-powered engine of the vehicle is not in operation. In the embodiment shown, the heater core 28′″ is in fluid communication with a source of heated fluid 74′″ through a conduit 76′″. The source of heated fluid 74′″ can be any conventional source of heated fluid such as the fuel-powered engine of the vehicle, for example, and the heated fluid can be any conventional fluid such as an engine coolant, for example. A valve 75′″ may be disposed in the conduit 76″ to selectively militate against a flow of heated fluid therethrough. It is understood that the heat exchanger 80′″ can be in fluid communication with the source of heated fluid 74′″ as desired without departing from the scope and spirit of the invention.

In the embodiment shown, the thermal energy exchanger 120 includes a main housing 122 having a hollow interior. The main housing 122 may be made of conventional materials such as polypropylene, for example. In the embodiment shown, the main housing 122 is generally rectangular in shape. It is understood that the main housing 122 can have other shapes as desired. The main housing 122 includes a first aperture 124 and a second aperture 126. The apertures 124, 126 are adapted to receive an inlet end 128 and an outlet end 130 of the conduit 84′″ therethrough. The inlet end 128 and the outlet end 130 extend through the respective apertures 124, 126 and into the fluid 90′″.

The fluid 90′″ includes a phase change material 56′″ disposed therein. The phase change material 56′″ is any material that melts and solidifies at certain temperatures and is capable of storing and releasing thermal energy such as a paraffin wax, an alcohol, water, and any combination thereof, for example. As shown in FIGS. 12 and 13, the phase change material 56′″ is encapsulated in a thermally conductive casing 60a′″, or coated with a thermally conductive coating 60b′″. The casing 60a′″ and the coating 60b′″ can be produced from any conventional material such as a polyethylene, for example. The casing 60a′″ and the coating 60b′″ permit the phase change material 56′″ to be disposed in the fluid 90 circulating through the conduit 84′″ and the heat exchanger 80′″. The encapsulated phase change material 56′″ is adapted to absorb thermal energy of the fluid 90′″ flowing through the heat exchanger 80′″ when the fuel-powered engine is not in operation. As illustrated in FIG. 13, the encapsulated phase change material 56′″ can include a thermally conductive material 58′″ disposed therein to further enhance the transfer of thermal energy if desired. It is understood that the inlet end 128 and the outlet end 130 of the conduit 84′″ can include a screen adapted to permit the flow of the fluid 90′″ therethrough, while militating against the flow of the encapsulated phase change material 56′″ from the thermal energy exchanger 120, if desired.

In use, when the fuel-powered engine of the vehicle is in operation, the fluid from the source of cooled fluid 30′″ circulates through the conduit 36′″. Accordingly, the fluid circulates through the evaporator core 24′″. The air from the inlet section 16′″ flows into the evaporator core 24′″ where the air is cooled to a desired temperature by a transfer of thermal energy from the air to the fluid from the source of cooled fluid 30′″. The conditioned air stream then exits the evaporator core 24′″. When the HVAC system 10′″ is not operating in the pull-down mode, the air from the evaporator core 24′″ is selectively permitted by the blend door 29′″ to flow into and through the heat exchanger 80′″. In the heat exchanger 80′″, the conditioned air absorbs thermal energy from the fluid 90′″ circulating therein. The transfer of thermal energy from the fluid 90′″ cools the fluid 90′″. Accordingly, the fluid 90′″ absorbs thermal energy from the phase change material 56′″ disposed therein. The transfer of thermal energy from the phase change material 56′″ to the fluid 90′″ cools and solidifies the phase change material 56′″. The conditioned air stream then flows through the heater core 28′″, which is not in operation, and into the outlet and distribution section.

When the fuel-powered engine of the vehicle is not in operation, the fluid from the source of cooled fluid 30′″ does not circulate through the conduit 36′″. Accordingly, the fluid does not circulate through the evaporator core 24′″. The air from the inlet section 16′″ flows into and through the evaporator core 24′″ where a temperature thereof is unchanged. The air then exits the evaporator core 24′″ and is selectively permitted by the blend door 29′″ to flow into the heat exchanger 80′″.

In the heat exchanger 80′″ the air is cooled to a desired temperature by a transfer of thermal energy from the air to the fluid 90′″ circulating therethrough. The pump 88′″ causes the fluid 90′″ to circulate through the conduit 84′″ and the thermal energy exchanger 120. The fluid 90′″ absorbs and transfers the thermal energy from the air to the phase change material 56′″ disposed therein. Thus, the phase change material 56′″ is caused to melt. The conditioned cooled air then exits the heat exchanger 80′″ and flows through the heater core 28′″, which is not in operation, and into the outlet and distribution section.

From the foregoing description, one ordinarily skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications to the invention to adapt it to various usages and conditions.

THERMAL ENERGY EXCHANGER FOR A HEATING, VENTILATING, AND AIR CONDITIONING SYSTEM

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CPC

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