GB773248A - Improvements in and relating to systems for cooling of air for example for aircraft pressurised spaces - Google Patents

Abstract

773,248. Air cooling installations; refrigerating. NORMALAIR, Ltd. March 9, 1955, No. 6893/55. Classas 29 and 64(3) Air is cooled by heat exchange first with air and then with water which is evaporated. In the apparatus shown, compressed air supplied to an aircraft cabin 22 is cooled first in a cooler 14, then in an indirectcontact heat exchanger 3 in which it heats water and converts it into steam which escapes to the atmosphere, then in a cooler 5, and finally by driving a turbine 20. Exhaust air from the cabin 22 flows, under the action of a fan 23 driven by the turbine 20, through the coolers 5, 14 to act as coolant. In the heat exchanger 3, the air flows through coiled tubes 16 immersed in water and connected to headers 17, 18. In the form shown, two air-cooling systems supplied by separate engine compressors are interconnected through a shut-off valve 15, so that if one engine.or air supply duct is damaged the compressor of the other engine can supply both systems. Bypasses for the turbines 20 and coolers 5 may be regulated by valves 25, 34 which are either manually operated or, as shown, operated by pistons 26 acted on by, springs and pneumatic pressure from air bled from the cabin supply ducts after leaving the heat exchangers 3. Bimetallic elements 31, 32 in the inlet and outlet ducts of the cabin regulate needle valves. 29, 30 controlling the leakage of the bled air, and so control the air pressure on the pistons.