Environmental air conditioning system

Patent metadata

Field	Value
Publication number	US-9657648-B2
Application number	US-201414553335-A
Country	US
Kind code	B2
Filing date	Nov 25, 2014
Priority date	Nov 25, 2014
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

An environmental air conditioning system is described for conditioning compressed air for supply as conditioned air. The system includes an airflow path to which the compressed air for ultimate distribution as conditioned air (i.e., airflow path compressed air) is supplied. Then airflow path has various components of an air cycle system, and also includes a power turbine outside of the air cycle that receives compressed air and discharges it as exhaust. The power turbine transfers power to a compressor in the air cycle system.

First claim

The invention claimed is:

1. An environmental air conditioning system for conditioning airflow path compressed air for supply as conditioned air, the system comprising:
an airflow path comprising a compressor that receives the airflow path compressed air, a first heat exchanger that receives and cools air from the compressor, a first turbine that receives air from the heat exchanger and discharges said air as conditioned air;
a second turbine that receives compressed air and discharges it as exhaust; and
a power transfer path that transfers power output from the first turbine and power output from the second turbine to the compressor,
wherein the system is configured to operate in a first mode in which power is transferred from the second turbine to the compressor when the first turbine does not provide sufficient power for the system to deliver conditioned air at a specified parameter, and a second mode in which power is not transferred from the first turbine to the compressor when the first turbine provides sufficient power for the system to deliver conditioned air at the specified parameter.

2. The system of claim 1 , further comprising a second heat exchanger that receives and cools the airflow path compressed air, and discharges cooled airflow path compressed air to the compressor.

3. The system of claim 1 , wherein the system is configured to operate the second turbine at outside ambient conditions of greater than standard day and to maintain the second turbine in a stand-by mode at other ambient conditions.

4. The system of claim 1 , further comprising a fan for moving air across or through a heat absorption side of the first heat exchanger, said fan powered by the power transfer path, an electric motor, or a third turbine not connected to the power transfer path.

5. The system of claim 1 , wherein the first turbine includes a variable-area nozzle.

6. The system of claim 1 , wherein the first turbine includes a two position nozzle.

7. An aircraft comprising the system of claim 1 , wherein the airflow path compressed air and compressed air for the second turbine are from the same source or different sources on board the aircraft, selected from an engine bleed, an auxiliary power unit bleed, or an electric powered compressor.

8. The aircraft of claim 7 , further comprising a second parallel environmental control system, wherein the first and second parallel environmental control systems are each configured to be operated in a first mode where the second turbine provides power to the compressor and a second mode where the second turbine is in a stand-by mode which does not provide power to the compressor.

9. The aircraft of claim 8 , wherein the first parallel environmental control system is operating in the first mode and the second parallel environmental control system is operating in the second mode.

10. A method of conditioning airflow path compressed air for supply as conditioned air, comprising:
further compressing the compressed air in a compressor;
cooling the further compressed air from the compressor in a first heat exchanger;
expanding and cooling the air in a first turbine, and discharging the cooled air as conditioned air;
introducing compressed air from a compressed air source, which is the same as or different than the compressed air supplied to the compressor, to a second turbine and discharging air from the second turbine to an exhaust; and
transferring power produced by the first and second turbines to the compressor,
wherein power is transferred from the second turbine to the compressor when the first turbine does not provide sufficient power for the system to deliver conditioned air at a specified parameter, and power is not transferred from the second turbine to the compressor when the first turbine provides sufficient power for the system to deliver conditioned air at the specified parameter.

11. The method of claim 10 , further comprising cooling the airflow path compressed air in a second heat exchanger and delivering the cooled airflow path compressed air to the compressor.

12. The method of claim 10 , wherein the airflow path compressed air has a pressure of less than or equal to 20 psia (138 kPa).

13. The method of claim 10 , wherein the second turbine is operated at outside ambient conditions of standard day and maintained in a stand-by mode at other ambient conditions.

14. The method of claim 10 , wherein the first turbine includes a variable-area discharge nozzle.

15. The system of claim 1 , further comprising a control valve disposed in a conduit that delivers the compressed air to the second turbine.

16. The system of claim 1 , wherein the system is configured to operate in the second mode when: (i) the aircraft is on the ground because the pressure of ambient air is relatively high, (ii) at cruise altitudes under standard day atmospheric conditions, or (iii) in climb or descent modes.

17. The system of claim 16 , wherein the system is configured to operate in the first mode at cruise altitudes under atmospheric conditions that deviate from standard day.

18. The system of claim 1 , wherein the system is configured to operate in the second mode when ambient temperature is colder than standard day.

Assignees

• Hamilton Sundstrand Corp

Inventors

• Bruno Louis J

Classifications

• B64D2013/0688

  with means for recirculating cabin air · CPC title

• B64D2013/0618

  with arrangements for reducing or managing bleed air, using another air source, e.g. ram air · CPC title

• B64D2013/0611

  combined with auxiliary power units (APU's) · CPC title

• B64D2013/0648

  with energy recovery means, e.g. using turbines · CPC title

• B64D13/06 Primary

  the air being conditioned (pressurising B64D13/02) · CPC title