Abstract: A system for controlling air flow comprises an inlet, a first compressor, a first pressure sensor, a second pressure sensor, a first temperature sensor, and a first controller. The inlet is configured to direct a first stream of air into the system. The first compressor is configured to pull in the first stream of air through the inlet and compress the first stream of air. The first pressure sensor senses a first pressure of the first stream of air prior to compression in the first compressor, the second pressure sensor senses a second pressure of the first stream of air after compression in the first compressor, and the first temperature sensor senses a temperature of the first stream of air after compression in the first compressor. The controller adjusts a speed of the first compressor based upon a comparison between a desired flow rate and a calculated flow rate.

Abstract: An inventive air conditioning system includes an air conditioning pack for receiving pressurized air and converting the pressurized air into conditioned air for an aircraft. Pressurized air is provided by a compressed air supply system that is fluidly connected to the air conditioning pack for providing air to the air conditioning pack. The compressed air system includes a compressor driven by an electric motor. The electric motor is commanded by a controller to provide pressurized air when needed. In particular, the controller commands the electric motor based upon a desired conditioned airflow that is to be provided by the air conditioning pack. For high altitude aircraft, applications, a diffuser is used to increase the efficiency of the compressor within the compressed air supply system.

Abstract: A compressor for use in an airplane fuel tank air purge system utilizes a low solidity diffuser. A low solidity diffuser is useful for providing air to an air separation module associated with the air purge system. In particular, a diffuser for such a compressor must be able to provide increased pressure ratios over a relatively great range of flow volumes. The low solidity diffuser of this invention is capable of providing increased pressure ratios over a relatively great range of flow volumes when compared to the prior art.

Abstract: An environmental control system and method are provided for conditioning water-vapor compressed air for supply as conditioned air. The environmental control system (8) includes two air cycle machines (9, 10) that rotate independent of each other. The air cycle machine (9) includes a turbine (11) that drives a fan (12), and the air cycle machine (10) includes a turbine (15) that drives a compressor (16). The environmental control system (8) further includes a primary heat exchanger (19) upstream of the compressor (16), a secondary heat exchanger (20) downstream of the compressor (16), are heater (21) downstream of the secondary heat exchanger (20), a condenser (22) downstream of the reheater (21), a water collector (24) downstream of the condenser (22), and three bypass control valves (28, 30, 32). In combination, the turbine (11), reheater (21), condenser (22), and water collector (24) form a dehumidification loop (34) for the environmental control system (8).