Environment control unit for turbine engine

• US 6,189,324 B1
• Filed: 10/05/1999
• Issued: 02/20/2001
• Est. Priority Date: 10/05/1999
• Status: Expired due to Term

• Current Assignee: Williams International Company LLC
• Original Assignee: Williams International Company LLC
• Inventors: Jones, John F., Thompson, Robert S. Jr., Williams, Samuel B.
• Primary Examiner(s): CAPOSSELA, RONALD C
• Application Number:
  US09/412,137
• Time in Patent Office: 504 Days
• Field of Search: 62/86, 62/87, 624/01, 621/72, 624/02
• US Class Current: 62/172
• CPC Class Codes: B64D 13/06 the air being conditioned pressurising B64D13/02
• CPC Class Codes: B64D 2013/0644 including electric motors or generators
• CPC Class Codes: B64D 41/00 Power installations for auxiliary purposes
• CPC Class Codes: Y02T 50/50 On board measures aiming to increase energy efficiency

Abstract

An environmental control unit to supply cool dry air to an aircraft cabin has a plurality of bleed air sources from an aircraft engine compressor supplying working fluid to an air cycle cooling circuit. An electronic control computer having a plurality of inputs and selects a bleed air source depending upon cabin cooling and pressurization requirements. A speed control valve responsive to an output from the control computer, modulates the flow of working fluid through a turbo-alternator, thereby synchronizing the frequency of electrical power produced by the turbo-alternator with that of an aircraft engine alternator. The turbo-alternator supplies additional electrical power to the aircraft, thereby minimizing the deleterious effect of warm air bled from the engine compressor on aircraft performance.

Claims

1. An environmental control unit for an aircraft having a control computer having a plurality of inputs and outputs, a cabin, and a turbine engine having a compressor, a bypass duct, an engine nacelle, and an alternator comprising:

a plurality of bleed air lines in fluid communication with said compressor for supplying pressurized working fluid to said environmental control unit;

a bleed air selector valve responsive to an output from said control computer in fluid communication with said plurality of bleed air lines for selecting a one of said bleed air lines as a source of working fluid;

a pressure regulator in fluid communication with said bleed air selector valve for limiting the pressure of the working fluid;

a selector valve responsive to an output from said control computer having an inlet in fluid communication with said pressure regulator, a first outlet in fluid communication with said aircraft cabin via a full bleed line to supply working fluid thereto in the event of a catastrophic failure of said environmental control unit, and a second outlet;

an air cycle cooling circuit for supplying cool dry air to said aircraft cabin comprising;

a bypass duct heat exchanger disposed in the bypass duct of said turbine engine, in fluid communication with the second outlet of said selector valve for cooling the working fluid;

a nacelle heat exchanger in fluid communication with said bypass duct heat exchanger having a ram air inlet and outlet for allowing flow of a cooling fluid therein, and an outlet for the working fluid;

a fan responsive to an output from said control computer disposed in fluid communication with said nacelle heat exchanger for enhancing the flow of cooling fluid therein;

a speed control valve responsive to an output from said control computer having an inlet in fluid communication with the outlet of said nacelle heat exchanger and an outlet for varying the flow of working fluid therethrough;

a turbo-alternator having an inlet in fluid communication with the outlet of said speed control valve, a turbine driven by the working fluid, a high speed alternator driven by the turbine to produce alternating current power for said aircraft, and an outlet;

a water separator having an inlet connected to the outlet of said turbo-alternator for separating water from the working fluid, and an outlet therefor; and

a mixer for mixing cooled working fluid with compressor bleed air having a first inlet in fluid communication with the outlet of said water separator, a second inlet for compressor bleed air, and an outlet;

a temperature control valve responsive to an output from said control computer having an inlet in fluid communication with the second outlet of said selector valve and an outlet in fluid communication with the inlet of said mixer for varying the flow of uncooled compressor bleed air into said mixer;

a mechanical check valve having an inlet in fluid communication with the outlet of said mixer and an outlet in fluid communication with the cabin of said aircraft to prevent fluid flow from the cabin into said mixer;

a pressure control valve responsive to an output from said control computer having an inlet in fluid communication with said cabin and an outlet that exhausts to atmosphere for controlling the pressure in said cabin; and

a differential pressure valve having an inlet in fluid communication with said cabin and an outlet that exhausts to atmosphere, for limiting the maximum pressurization of said aircraft cabin.

2. An environmental control unit as claimed in claim 1 wherein said bypass duct heat exchanger comprises a plurality of heat exchanging elements.

3. An environmental control unit as claimed in claim 1 further comprising an outlet damper disposed at the outlet of said nacelle heat exchanger for controlling the flow of cooling fluid therein.

4. An environmental control unit as claimed in claim 1 further comprising a first input to said control computer indicative of the rotational velocity of said turbo-alternator and a second input to said control computer indicative of the rotational velocity of said engine alternator, wherein said speed control valve is positioned responsive to the output from said control computer to synchronize the rotational velocity of said turbo-alternator with that of the engine alternator.

5. An environmental control unit as claimed in claim 1 further comprising a voltage rectifier circuit electrically connected to the high speed alternator for converting the alternating current power produced thereby into direct current power.

6. An environmental control unit as claimed in claim 1 wherein said pressure control valve is positioned responsive to the output from said control computer to vary the pressure in the aircraft cabin from ambient pressure at a departure location to ambient pressure at an arrival location over the course of an aircraft flight.

11. An environmental control unit as claimed in claim 2 further comprising a voltage rectifier circuit electrically connected to the high speed alternator for converting the alternating current power produced thereby into direct current power.

12. An environmental control unit as claimed in claim 2 wherein said pressure control valve is positioned responsive to the output from said control computer to vary the pressure in the aircraft cabin from ambient pressure at a departure location to ambient pressure at an arrival location over the course of an aircraft flight.

7. An environmental control unit for an aircraft having a control computer having a plurality of inputs and outputs, a cabin, and a turbine engine having a compressor, a bypass duct, an engine nacelle, and an alternator comprising:

a plurality of bleed air lines in fluid communication with said compressor for supplying pressurized working fluid to said environmental control unit;

a first bleed air selector valve responsive to an output from said control computer in fluid communication with said plurality of bleed air lines for selecting a one of said bleed air lines as a source of working fluid;

a second bleed air selector valve responsive to an output from said control computer in fluid communication with said plurality of bleed air lines for selecting a one of said bleed air lines as a source of working fluid;

a first pressure regulator having an inlet in fluid communication with said first bleed air selector valve for limiting the pressure of the working fluid and an outlet;

a second pressure regulator having an inlet in fluid communication with said second bleed air selector valve for limiting the pressure of the working fluid and an outlet;

a full bleed valve responsive to an output from said control computer having an inlet in fluid communication with a one of said plurality of bleed air lines and an outlet in fluid communication with said cabin via a full bleed line to supply working fluid thereto in the event of a catastrophic outlet of said environmental control unit;

an air cycle cooling circuit for supplying cool dry air to said aircraft cabin comprising;

a bypass duct heat exchanger disposed in the bypass duct of said turbine engine, in fluid communication with the outlet of said first pressure regulator for cooling the working fluid;

a nacelle heat exchanger in fluid communication with said bypass duct heat exchanger having a ram air inlet and outlet for allowing flow of a cooling fluid therein, and an outlet for the working fluid;

a fan responsive to an output from said control computer disposed in fluid communication with said nacelle heat exchanger for enhancing the flow of cooling fluid therein;

a speed control valve responsive to an output from said control computer having an inlet in fluid communication with the outlet of said nacelle heat exchanger and an outlet for varying the flow of working fluid therethrough;

a turbo-alternator having an inlet in fluid communication with the outlet of said speed control valve, a turbine driven by the working fluid, a high speed alternator driven by the turbine to produce alternating current power for said aircraft, and an outlet;

a water separator having an inlet connected to the outlet of said turbo-alternator for separating water from the working fluid, and an outlet therefor; and

a mixer for mixing cooled working fluid with compressor bleed air having a first inlet in fluid communication with the outlet of said water separator, a second inlet for compressor bleed air, and an outlet;

a temperature control valve responsive to an output from said control computer having an inlet in fluid communication with the outlet of said second pressure regulator and an outlet in fluid communication with the inlet of said mixer for varying the flow of uncooled compressor bleed air into said mixer;

a mechanical check valve having an inlet in fluid communication with the outlet of said mixer and an outlet in fluid communication with the cabin of said aircraft to prevent fluid flow from the cabin into said mixer;

a pressure control valve responsive to an output from said control computer having an inlet in fluid communication with said cabin and an outlet that exhausts to atmosphere for controlling the pressure in said cabin; and

a mechanically operated differential pressure valve having an inlet in fluid communication with said cabin and an outlet that exhausts to atmosphere, for limiting the maximum pressurization of said aircraft cabin.

8. An environmental control unit as claimed in claim 7 wherein said bypass duct heat exchanger comprises a plurality of heat exchanging elements.

9. An environmental control unit as claimed in claim 7 further comprising an outlet damper disposed at the outlet of said nacelle heat exchanger for controlling the flow of cooling fluid therein.

10. An environmental control unit as claimed in claim 7 further comprising a first input to said control computer indicative of the rotational velocity of said turbo-alternator and a second input to said control computer indicative of the rotational velocity of said engine alternator, wherein said speed control valve is positioned responsive to the output from said control computer to synchronize the rotational velocity of said turbo-alternator with that of the engine alternator.

13. An environmental control unit for an aircraft having a control computer having a plurality of inputs and outputs, a cabin, and a turbine engine having a compressor, a bypass duct, an engine nacelle, and an alternator comprising:

a plurality of bleed air lines in fluid communication with said compressor for supplying pressurized working fluid to said environmental control unit;

a bleed air selector valve responsive to an output from said control computer in fluid communication with said plurality of bleed air lines for selecting a one of said bleed air lines as a source of working fluid;

a pressure regulator in fluid communication with said bleed air selector valve for limiting the pressure of the working fluid;

a selector valve responsive to an output from said control computer having an inlet in fluid communication with said pressure regulator, a first outlet in fluid communication with said aircraft cabin via a full bleed line to supply working fluid thereto in the event of a catastrophic failure of said environmental control unit, and a second outlet;

an air cycle cooling circuit for supplying cool dry air to said aircraft cabin comprising;

a compressor having an inlet in fluid communication with the second outlet of said selector valve and an outlet, for compressing working fluid for the air cycle cooling circuit;

a bypass duct heat exchanger disposed in the bypass duct of said turbine engine, in fluid communication with the outlet of said compressor for cooling the working fluid;

a nacelle heat exchanger in fluid communication with said bypass duct heat exchanger having a ram air inlet and outlet for allowing flow of a cooling fluid therein, and an outlet for the working fluid;

a fan responsive to an output from said control computer disposed in fluid communication with said nacelle heat exchanger for enhancing the flow of cooling fluid therein;

a speed control valve responsive to an output from said control computer having an inlet in fluid communication with the outlet of said nacelle heat exchanger and an outlet for varying the flow of working fluid therethrough;

a turbo-alternator having an inlet in fluid communication with the outlet of said speed control valve, a turbine driven by the working fluid, a high speed alternator driven by the turbine to produce alternating current power to said aircraft, and an outlet, said turbo-alternator further driving a shaft mechanically coupled to said compressor for rotation thereof;

a water separator having an inlet connected to the outlet of said turbo-alternator for separating water from the working fluid, and an outlet therefor; and

a mixer for mixing cooled working fluid with compressor bleed air having a first inlet in fluid communication with the outlet of said water separator, a second inlet for compressor bleed air, and an outlet;

a temperature control valve responsive to an output from said control computer having an inlet in fluid communication with the second outlet of said selector valve and an outlet in fluid communication with the inlet of said mixer for varying the flow of uncooled compressor bleed air into said mixer;

a mechanical check valve having an inlet in fluid communication with the outlet of said mixer and an outlet in fluid communication with the cabin of said aircraft to prevent fluid flow from the cabin into said mixer;

a pressure control valve responsive to an output from said control computer having an inlet in fluid communication with said cabin and an outlet that exhausts to atmosphere for controlling the pressure in said cabin; and

a mechanically operated differential pressure valve having an inlet in fluid communication with said cabin and an outlet that exhausts to atmosphere, for limiting the maximum pressurization of said aircraft cabin.

14. An environmental control unit as claimed in claim 13 wherein said bypass duct heat exchanger comprises a plurality of heat exchanging elements.

15. An environmental control unit as claimed in claim 13 further comprising an outlet damper disposed at the outlet of said nacelle heat exchanger for controlling the flow of cooling fluid therein.

16. An environmental control unit as claimed in claim 13 further comprising a first input to said control computer indicative of the rotational velocity of said turbo-alternator and a second input to said control computer indicative of the rotational velocity of said engine alternator, wherein said speed control valve is positioned responsive to the output from said control computer to synchronize the rotational velocity of said turbo-alternator with that of the engine alternator.

17. An environmental control unit as claimed in claim 13 further comprising a voltage rectifier circuit electrically connected to the high speed alternator for converting the alternating current power produced thereby into direct current power.

18. An environmental control unit as claimed in claim 13 wherein said pressure control valve is positioned responsive to the output from said control computer to vary the pressure in the aircraft cabin from ambient pressure at a departure location to ambient pressure at an arrival location over the course of an aircraft flight.