US 4,535,606 AGranted

High efficiency air cycle air conditioning system

AssigneeUnited Technologies Corporation

InventorGeorge C. Rannenberg

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Abstract

A high efficiency air cycle air conditioning system (10), driven and charged by a gas turbine engine (15), operates in a closed-loop, Brayton cycle. The system includes a main (bootstrap) compressor (75) discharging to a sink heat exchanger (85) which in turn discharges to a regenerative heat exchanger (110). Air is ducted from the regenerative heat exchanger to an expansion turbine (120) where the air is chilled and then ducted to load (20). Air exhausted from the load is again ducted through the regenerative heat exchanger where the load exhaust air precools turbine inlet air. The capacity (operating pressures) of, and input power to the system are controlled by modulation of charge air provided to the system from the gas turbine engine and if desired, may be further controlled by selective bleeding of air from the system, selective bypassing of the system turbine with refrigerant, or modulation of shaft input power to the main compressor.

Claims22

Dependent claims

In an air cycle refrigeration system for providing chilled refrigerant air to a load for the cooling thereof, said system being adapted for the supply thereto of compressed charge air from the compressor discharge section of a gas turbine engine and comprising a bootstrap compressor for increasing the pressure of said refrigerant air, airflow exhausted from said refrigerant compressor being directed to an expansion turbine for cooling thereby and discharge therefrom to said load, said expansion turbine and bootstrap compressor being mechanically interconnected whereby said expansion turbine provides, a measure of input power for driving said bootstrap compressor, said air cycle refrigeration system being characterized by:

means for exhausting substantially the entire airflow from said load to an inlet of said bootstrap compressor whereby said bootstrap compressor, said expansion turbine and said load define a closed-loop circulatory system;
a first conduit connecting said compressor discharge section of said gas turbine engine with said closed-loop circulatory system between said expansion turbine discharge and said bootstrap compressor inlet for providing said charge air to said refrigeration system whereby the system air pressure may be maintained at least at substantially the same level as the gas turbine engine compressor discharge pressure;
means for sensing the cooling requirements of said load and providing an output signal indicative thereof;
and
a first control means disposed in said refrigeration system and responsive to the output signal from said sensing means for controlling the flow of air through said refrigeration system, thereby controlling the capacity thereof in response to the cooling requirements of said load.

2 more elements

A method of cooling a load with an air cycle refrigeration system, said method comprising the steps of providing charge air from the compressor discharge section of a gas turbine engine to the inlet of a main compressor of said refrigeration system, cooling said compressed supply air by heat transfer therefrom to a heat sink, chilling and expanding said compressed air in an expansion turbine and cooling said load by passing said chilled and expanded air therethrough, said method being characterized by the steps of:

supplying said charge air to said refrigeration system without substantially lowering the pressure thereof;
and
exhausting said chilled and expanded air from said load and ducting substantially all of said load exhaust air to said inlet of said main compressor,
whereby said refrigeration system operated in a closed-loop Brayton cycle at pressures at least substantially as high as the compressor discharge pressure of said gas turbine engine.

1 more element

Dependencies are inferred from the claim text.