Patent US6694763B2 successfully refreshed from Google Patents.
US6694763B2
Expired / Lapsed
US
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Method for operating a transcritical refrigeration system
Assignee: Praxair Technology Inc
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Filing: 2002-05-30
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Granted: 2004-02-24
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Expires: 2022-05-30
Abstract
Abstract A method for operating a transcritical refrigeration system wherein a more optimal compressor parameter such as output pressure, pressure ratio or power consumption is determined using heat exchanger refrigerant inflow temperatures and/or outflow temperatures and also the enthalpy change across the evaporator and adjusting the compressor operation or refrigerant fluid working mass accordingly.
Inventors
- 👤 Henry Edward Howard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:46
CPC Classifications
F; F25; F25B; F25B9/00; F25B9/002; F25B9/008; F25B49/00; F25B49/02; F25B49/022; F25B2309/00; F25B2309/06; F25B2309/061; F25B2341/00; F25B2341/06; F25B2341/063; F25B2500/00; F25B2500/18; F25B2600/00; F25B2600/02; F25B2600/027; F25B2600/17; F25B2700/00; F25B2700/13; F25B2700/131; F25B2700/19; F25B2700/193; F25B2700/1931; F25B2700/1933; F25B2700/21; F25B2700/2115; F25B2700/21151; F25B40/00
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
249 words
A method for operating a transcritical refrigeration system comprising: (A) compressing a refrigerant fluid in a compressor to be at a supercritical pressure, passing the compressed refrigerant fluid having a temperature to a heat exchanger, cooling the compressed refrigerant fluid in the heat exchanger, withdrawing the cooled compressed refrigerant fluid having a temperature from the heat exchanger, and expanding the resulting refrigerant fluid to a subcritical pressure, said subcritical pressure refrigerant fluid being at least in part in liquid form; (B) vaporizing subcritical pressure refrigerant fluid to provide refrigeration to a heat load said vaporizing subcritical pressure refrigerant fluid having an enthalpy change, passing vaporized refrigerant fluid having a temperature to the heat exchanger, warming the vaporized refrigerant fluid by indirect heat exchange with the cooling compressed refrigerant fluid, withdrawing the resulting warmed refrigerant fluid having a temperature from the heat exchanger, and passing the withdrawn refrigerant fluid to the compressor; (C) ascertaining at least two of the temperature of the compressed refrigerant fluid, temperature of the cooled compressed refrigerant fluid, temperature of the vaporized refrigerant fluid, and temperature of the warmed refrigerant fluid, and ascertaining the enthalpy change of the vaporizing subcritical pressure refrigerant; (D) monitoring an operating parameter of the compressor, and using the said ascertained temperatures and the said ascertained enthalpy change to determine a more efficient value for said operating parameter; and (E) adjusting the operation of the compressor so that the value of said operating parameter is closer to the said more efficient value.
Claim 2
Independent Claim
249 words
A method for operating a transcritical refrigeration system comprising: (A) compressing a refrigerant fluid in a compressor to be at a supercritical pressure, passing the compressed refrigerant fluid having a temperature to a heat exchanger, cooling the compressed refrigerant fluid in the heat exchanger, withdrawing the cooled compressed refrigerant fluid having a temperature from the heat exchanger, and expanding the resulting refrigerant fluid to a subcritical pressure, said subcritical pressure refrigerant fluid being at least in part in liquid form; (B) vaporizing subcritical pressure refrigerant fluid to provide refrigeration to a heat load said vaporizing subcritical pressure refrigerant fluid having an enthalpy change, passing vaporized refrigerant fluid having a temperature to the heat exchanger, warming the vaporized refrigerant fluid by indirect heat exchange with the cooling compressed refrigerant fluid, withdrawing the resulting warmed refrigerant fluid having a temperature from the heat exchanger, and passing the withdrawn refrigerant fluid to the compressor; (C) ascertaining at least two of the temperature of the compressed refrigerant fluid, temperature of the cooled compressed refrigerant fluid, temperature of the vaporized refrigerant fluid, and temperature of the warmed refrigerant fluid, and ascertaining the enthalpy change of the vaporizing subcritical pressure refrigerant; (D) monitoring an operating parameter of the compressor, and using the said ascertained temperatures and the said ascertained enthalpy change to determine a more efficient value for said operating parameter; and (E) adjusting the operation of the compressor so that the value of said operating parameter is closer to the said more efficient value.
Claim 3
Dependent Claim
20 words
The method of claim 1 wherein the operating parameter is the output pressure of the refrigerant fluid from the compressor.
Claim 4
Dependent Claim
36 words
The method of claim 1 wherein the operating parameter is the pressure ratio of the pressure of the refrigerant fluid passed out from the compressor and the pressure of the refrigerant fluid passed into the compressor.
Claim 5
Dependent Claim
16 words
The method of claim 1 wherein the operating parameter is the power consumption of the compressor.
Claim 6
Dependent Claim
12 words
The method of claim 1 wherein the refrigerant fluid comprises carbon dioxide.
Claim 7
Dependent Claim
33 words
The method of claim 5 wherein the supercritical pressure is within the range of from 1100 to 2000 psia and the subcritical pressure is within the range of from 200 to 700 psia.
Claim 8
Dependent Claim
16 words
The method of claim 1 wherein the enthalpy change is ascertained using a specified heat load.
Claim 9
Dependent Claim
16 words
The method of claim 1 wherein the enthalpy change is ascertained using the actual heat load.
Claim 10
Independent Claim
255 words
A method for operating a transcritical refrigeration system comprising: (A) compressing a refrigerant fluid having a working mass in a compressor to be at a supercritical pressure, passing the compressed refrigerant fluid having a temperature to a heat exchanger, cooling the compressed refrigerant fluid in the heat exchanger, withdrawing the cooled compressed refrigerant fluid having a temperature from the heat exchanger, and expanding the resulting refrigerant fluid to a subcritical pressure said subcritical pressure refrigerant fluid being at least in part in liquid form; (B) vaporizing subcritical pressure refrigerant fluid to provide refrigeration to a heat load said vaporizing subcritical pressure refrigerant fluid having an enthalpy change, passing vaporized refrigerant fluid having a temperature to the heat exchanger, warming the vaporized refrigerant fluid by indirect heat exchange with the cooling compressed refrigerant fluid, withdrawing the resulting warmed refrigerant fluid having a temperature from the heat exchanger, and passing the withdrawn refrigerant fluid to the compressor; (C) ascertaining at least two of the temperature of the compressed refrigerant fluid, temperature of the cooled compressed refrigerant fluid, temperature of the vaporized refrigerant fluid, and temperature of the warmed refrigerant fluid, and ascertaining the enthalpy change of the vaporizing subcritical pressure refrigerant; (D) monitoring an operating parameter of the compressor, and using the said ascertained temperatures and the said ascertained enthalpy change to determine a more efficient value for said operating parameter; and (E) adjusting the working mass of the refrigerant fluid so that the value of said operating parameter is closer to the said more efficient value.
Claim 11
Independent Claim
255 words
A method for operating a transcritical refrigeration system comprising: (A) compressing a refrigerant fluid having a working mass in a compressor to be at a supercritical pressure, passing the compressed refrigerant fluid having a temperature to a heat exchanger, cooling the compressed refrigerant fluid in the heat exchanger, withdrawing the cooled compressed refrigerant fluid having a temperature from the heat exchanger, and expanding the resulting refrigerant fluid to a subcritical pressure said subcritical pressure refrigerant fluid being at least in part in liquid form; (B) vaporizing subcritical pressure refrigerant fluid to provide refrigeration to a heat load said vaporizing subcritical pressure refrigerant fluid having an enthalpy change, passing vaporized refrigerant fluid having a temperature to the heat exchanger, warming the vaporized refrigerant fluid by indirect heat exchange with the cooling compressed refrigerant fluid, withdrawing the resulting warmed refrigerant fluid having a temperature from the heat exchanger, and passing the withdrawn refrigerant fluid to the compressor; (C) ascertaining at least two of the temperature of the compressed refrigerant fluid, temperature of the cooled compressed refrigerant fluid, temperature of the vaporized refrigerant fluid, and temperature of the warmed refrigerant fluid, and ascertaining the enthalpy change of the vaporizing subcritical pressure refrigerant; (D) monitoring an operating parameter of the compressor, and using the said ascertained temperatures and the said ascertained enthalpy change to determine a more efficient value for said operating parameter; and (E) adjusting the working mass of the refrigerant fluid so that the value of said operating parameter is closer to the said more efficient value.
Claim 12
Dependent Claim
20 words
The method of claim 9 wherein the operating parameter is the output pressure of the refrigerant fluid from the compressor.
Claim 13
Dependent Claim
36 words
The method of claim 9 wherein the operating parameter is the pressure ratio of the pressure of the refrigerant fluid passed out from the compressor and the pressure of the refrigerant fluid passed into the compressor.
Claim 14
Dependent Claim
16 words
The method of claim 9 wherein the operating parameter is the power consumption of the compressor.
Claim 15
Dependent Claim
12 words
The method of claim 9 wherein the refrigerant fluid comprises carbon dioxide.
Claim 16
Dependent Claim
33 words
The method of claim 13 wherein the supercritical pressure is within the range of from 1100 to 2000 psia and the subcritical pressure is within the range of from 200 to 700 psia.
Claim 17
Dependent Claim
16 words
The method of claim 9 wherein the enthalpy change is ascertained using a specified heat load.
Claim 18
Dependent Claim
16 words
The method of claim 9 wherein the enthalpy change is ascertained using the actual heat load.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2007-02-23 | 2007-08-25 | 2008-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-02-23 | 2011-08-25 | 2012-02-24 | $3760.00 | Window Closed / Lapsed |
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