초록 ▼

In an air conditioning system for an aircraft cabin, stale air is withdrawn from the cabin, then filtered, compressed and cooled in a recirculation loop which returns the reconditioned air to an air distribution manifold that supplies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 thr

In an air conditioning system for an aircraft cabin, stale air is withdrawn from the cabin, then filtered, compressed and cooled in a recirculation loop which returns the reconditioned air to an air distribution manifold that supplies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. The filtered, compressed and cooled recirculation air is combined with the fresh air delivered by the output turbine stage of the air cycle machine, and spent air from the discharge side of the recirculation power turbine is, prior to being discharged overboard, ducted through a primary heat exchanger used for cooling of the fresh engine bleed air that supplies the air cycle machine. In an alternate embodiment, the cabin-to-ambient pressure differential for driving the recirculation loop power turbine is obtained from pressurized air (normally dumped directly overboard) in an avionics compartment of the aircraft, and the supply of stale cabin air for recirculation is provided by air drawn from a cargo compartment of the aircraft, which has air that is normally cooler than cabin air, thus eliminating the need for post-compression cooling of the recirculation air.

대표청구항 ▼

In an air conditioning system having a primary air supply for introducing fresh air into the interior of an aircraft, and wherein the aircraft has a first compartment that is, during at least certain flight conditions, maintained at a pressure higher than that of ambient air surrounding the exterior

In an air conditioning system having a primary air supply for introducing fresh air into the interior of an aircraft, and wherein the aircraft has a first compartment that is, during at least certain flight conditions, maintained at a pressure higher than that of ambient air surrounding the exterior of the aircraft, the improvement in said air conditioning system of a recirculation air supply, comprising: an air driven turbine means including an air input and an air output; first duct means for ducting air from said first compartment to said input of said turbine means; second duct means for ducting air from said air output of said turbine means to an overboard exhaust in communication with ambient air so as to power said turbine means by the differential pressure existing between air in said first compartment and ambient air; a source of filtered stale air available from the interior of said aircraft; air compressor means having an air input and an air output; third duct means for ducting said filtered stale air from said source thereof to said input of said compressor means; and fourth duct means for receiving filtered and compressed air discharged at the output of said air compressor means and for recirculating said filtered and compressed air back into the interior of the aircraft.