THERMALLY ACTIVATED HIGH EFFICIENCY HEAT PUMP

• US 20100218513A1
• Filed: 08/28/2007
• Published: 09/02/2010
• Est. Priority Date: 08/28/2007
• Status: Active Grant

• Current Assignee: Carrier Corporation (Carrier Global Corporation)
• Original Assignee: Carrier Corporation (Carrier Global Corporation)
• Inventors: Taras, Michael F., Vaisman, Igor B., Sangiovanni, Joseph J.
• Granted Patent: US 8,297,065 B2
• Time in Patent Office: Days
• US Class Current: 62/6
• CPC Class Codes: F01K 17/005 by means of a heat pump heat pumps systems per se F25B
• CPC Class Codes: F01K 25/06 using mixtures of different fluids plants using mixtures of steam and gas F01K21/04
• CPC Class Codes: F01K 7/32 the engines using steam of critical or overcritical pressure
• CPC Class Codes: F01K 7/34 the engines being of extraction or non-condensing type; Use of steam for feed-water heating feed-water heaters in general F22D
• CPC Class Codes: F25B 2309/061 with cycle highest pressure above the supercritical pressure
• CPC Class Codes: F25B 2400/23 Separators
• CPC Class Codes: F25B 27/00 Machines, plants or systems, using particular sources of energy F25B30/06 takes precedence
• CPC Class Codes: Y02E 20/14 Combined heat and power generation [CHP]

Abstract

A vapor compression cycle system is combined with a Rankine cycle system, with the two systems having a common suction accumulator from which the compressor draws refrigerant vapor for the vapor compression cycle system and from which a pump draws liquid refrigerant for circulation within the Rankine cycle system. The vapor from the Rankine cycle system expander is passed to the compressor discharge to provide a mixture which is circulated within the vapor compression cycle system to obtain improved performance. The heat exchangers are sized so as to obtain a non-complete evaporation, with the resulting two-phase fluid passing to the suction accumulator to provide liquid refrigerant to the Rankine cycle system and vapor refrigerant to the vapor compression cycle system.

Claims

1.

a vapor compression cycle system, which includes, in a serial refrigerant flow communication, a compressor, a first heat exchanger, an expansion device, a second heat exchanger and a suction accumulator;

a Rankine cycle system, which includes, in a serial flow communication, the suction accumulator, a liquid refrigerant pump, a boiler and an expander;

said compressor having a suction inlet and a discharge outlet, and said expander having an inlet and an outlet, and further wherein said expander outlet is fluidly connected to said compressor outlet to provide a combined flow for circulation through said first heat exchanger, said expansion device, said second heat exchanger and said suction accumulator of said vapor compression system.

2. A thermally activated heat pump as set forth in claim 1 wherein said refrigerant operates in a subcritical cycle, at least for a portion of the time.

3. A thermally activated heat pump as set forth in claim 1 wherein said refrigerant operates in a transcritical cycle, at least for a portion of the time.

4. A thermally activated heat pump as set forth in claim 1 wherein said refrigerant is a BZT fluid.

5. A thermally activated heat pump as set forth in claim 1 wherein said refrigerant is a mixture of fluids.

6. A thermally activated heat pump as set forth in claim 5 wherein at least one fluid of said mixture of fluids is a lubricant.

7. A thermally activated heat pump as set forth in claim 1 wherein an economizer heat exchanger provides a thermal contact between liquid refrigerant outgoing from said pump of said Rankine cycle system and liquid refrigerant entering said expansion device of said vapor compression cycle system.

exchanger is used as an evaporator providing cooling duty as an indoor unit.

9. A thermally activated heat pump as set forth in claim 1 wherein, said first heat exchanger is used for evaporation as an outdoor unit and said second heat exchanger is used to provide heating duty as an indoor unit.

10. A thermally activated heat pump as set forth in claim 1 wherein a reversing valve is installed downstream of a point where refrigerant flow from said expander and refrigerant flow from said compressor are combined, said first heat exchanger is used as an outdoor unit, said second heat exchanger is used as an indoor unit, and said reversing valve is controlled to selectively provide appropriate refrigerant communication with said outdoor unit and said indoor unit to execute cooling and heating duties.

11. A thermally activated heat pump as set forth in claim 1 wherein, said refrigerant contains a lubricating oil, an oil separator is installed downstream of a point where refrigerant flow from said expander and refrigerant flow from said compressor are combined.

12. A thermally activated heat pump as set forth in claim 11 wherein the lubricating oil separated in said oil separator is returned to said compressor.

13. A thermally activated heat pump as set forth in claim 11 wherein at least a portion of the separated lubricating oil is returned to said expander.

14. A thermally activated heat pump as set forth in claim 1 wherein a regenerating heat exchanger provides a thermal contact between refrigerant outgoing from said expander and refrigerant entering said boiler.

16. A thermally activated heat pump as set forth in claim 1 wherein said expander and a generator are positioned on the same shaft.

17. A thermally activated heat pump as set forth in claim 1 wherein said thermally activated heat pump comprises a topping system of a cascade system.

18. A thermally activated heat pump as set forth in claim 1 wherein said thermally activated heat pump comprises a bottoming system of a cascade system.

19. A thermally activated heat pump as set forth in claim 17 wherein:

said topping system of said cascade system comprises a Brayton cycle system;

said Brayton cycle system comprises at least a compressor, a combustor, a turbine, and a cascade heat exchanger; and

said cascade heat exchanger provides a thermal contact between said bottoming system and said topping system

20. A thermally activated heat pump as set forth in claim 19 wherein said compressor of said topping system and said turbine of said topping system are positioned on the same shaft.

21. A thermally activated heat pump as set forth in claim 19 wherein said expander and a generator are positioned on the same shaft.

15.

22. A method of combining a vapor compression cycle system with a Rankine cycle system to obtain increased thermodynamic efficiency in operation, comprising the steps of:

providing a vapor compression cycle system to include, in a serial flow communication, a compressor, a reversing valve, an outdoor heat exchanger, a first

providing a Rankine cycle system, which includes, in a serial flow communication, the suction accumulator, a liquid refrigerant pump, a second pass of the economizer heat exchanger, a boiler and an expander.

23. A method as set forth in claim 22 wherein the compressor includes a suction inlet and a discharge outlet, and said expander includes an inlet and an outlet, and further including the steps of fluidly connecting said expander outlet to said compressor outlet and providing a combined flow to be circulated through said vapor compression cycle system.

24. A method as set forth in claim 23 and including the steps of, when operating in a cooling mode, combining the flow of vapor from said compressor and from said expander and passing it through the reversing valve and then to the outdoor heat exchanger.

25. A method as set forth in claim 23 and including the steps of, when operating in a heating mode, combining the flow of vapor from said compressor and from said expander and passing it through the reversing valve and then to the indoor heat exchanger.

26. A method as set forth in claim 23 and including the steps of, when operating in a cooling mode, selectively controlling said reversing valve to pass the flow of refrigerant from the indoor heat exchanger through the reversing valve and then to the suction accumulator.

27. A method as set forth in claim 25 wherein said indoor heat exchanger is sized for a non-complete evaporation, and including the step of passing the flow of both vapor and liquid refrigerant from said indoor heat exchanger to said suction accumulator.

liquid from said suction accumulator to said pump.

29. A method as set forth in claim 23 and including the steps of, when operating in a heating mode, selectively controlling said reversing valve to pass the flow of refrigerant from the outdoor heat exchanger, through the reversing valve and then to the suction accumulator.

30. A method as set forth in claim 29 wherein said outdoor heat exchanger is sized for a non-complete evaporation, and including the step of passing the flow of both vapor and liquid refrigerant from said outdoor heat exchanger to said suction accumulator.

31. A method as set forth in claim 30 and including the steps of passing the flow of vapor from said suction accumulator to said compressor and the flow of liquid from said suction accumulator to said pump.

33. A method as set forth in claim 29 wherein said liquid contains a lubricant.

34. A method as set forth in claim 22 wherein said refrigerant operates in a subcritical cycle, at least for a portion of the time.

35. A method as set forth in claim 22 wherein said refrigerant operates in a transcritical cycle, at least for a portion of the time.

36. A method as set forth in claim 22 wherein said refrigerant is a refrigerant mixture.

pump of said Rankine cycle system and liquid refrigerant entering said expansion device of said vapor compression cycle system.

38. A method as set forth in claim 22 wherein said first heat exchanger is used for heat rejection as an outdoor unit and said second heat exchanger is used as an evaporator providing cooling duty as an indoor unit.

39. A method as set forth in claim 22 wherein, said first heat exchanger is used for evaporation as an outdoor unit and said second heat exchanger is used to provide heating duty as an indoor unit.

40. A method as set forth in claim 22 wherein a reversing valve is installed downstream of a point where refrigerant flow from said expander and refrigerant flow from said compressor are combined, said first heat exchanger is used as an outdoor unit, said second heat exchanger is used as an indoor unit, and said reversing valve is selectively controlled to provide appropriate refrigerant communication with said outdoor unit and said indoor unit to execute cooling and heating duties.

41. A method as set forth in claim 22 wherein, said refrigerant contains a lubricating oil, an oil separator is installed downstream of a point where refrigerant flow from said expander and refrigerant flow from said compressor are combined.

42. A method as set forth in claim 22 wherein oil separated in said oil separator is returned to said compressor.

43. A method as set forth in claim 22 wherein at least a portion of separated oil is returned to said expander.

expander and refrigerant entering said boiler.

32. A method as set forth in claim 28 wherein said liquid contains a lubricant.