Abstract: Compressed air is directed through an inert gas generator which removes oxygen to produce a nitrogen enriched, combustibly inert air or gas. The converter is sized to only meet the relatively low flow rate requirements of the system during which times the combustibly inert air or gas is delivered directly to a utilization site. The system further includes a high pressure storage container in which a pressurized precharge of the combustibly inert air or gas is stored. Combustibly inert air is released from such high pressure storage container for providing the higher flow rate requirements of the system. The system may be used aboard an aircraft for inerting fuel tanks. It may include a separate compressor for filling the high pressure storage container.

Abstract: In an air conditioning system for an aircraft cabin, stale air is withdrawn from the cabin, then filtered, compressed and cooled in a recirculation loop which returns the reconditioned air to an air distribution manifold that supplies the cabin with fresh air. The compression stage moves the air through the recirculation loop and is provided by an air compressor driven by a power turbine that is in turn rotated by a flow of cabin air to an overboard exhaust nozzle caused by a cabin-to-ambient pressure differential. Cooling is provided by an air/air heat exchanger that transfers heat from the recirculation air, warmed by the compression stage, to cooler air discharged from the output side of the power turbine and flowing to the overboard exhaust nozzle. In one embodiment, the foregoing recirculation loop is integrated with an air cycle machine refrigeration stage of a conventional cabin air conditioning system supplied by fresh engine bleed air.