Improvements in and relating to closed liquid-circulating cooling systems

摘要

969,804. Closed liquid coolant circulation systems. G. BAYARD. April 30, 1962 [May 13, 1961], No. 16412/62. Heading F4U. Apparatus for cooling the liquid coolant, e.g. of electronic equipment in an aircraft, comprises an air cooled heat exchanger 11, means 7 capable of causing the liquid to bypass the heat exchanger when the temperature of the cooling air rises above a predetermined value, means leading from the heat exchanger and from the by-pass to convey the liquid to a pair of evaporators 16, 17 arranged in series, the evaporators containing a second liquid, e.g. methyl alcohol, and means capable of controlling the boiling temperature of said second liquid. As shown, liquid to be cooled enters distribution cock 7 which is controlled by a heat sensitive probe 9 which records the temperature of the air-cooling heat exchanger 11. If the temperature sensed is below e.g. 50‹ C. then cock 7 diverts the liquid through the heat exchanger 11, if above, then the heat exchanger is by-passed. Both by-pass and heat exchanger liquid enters evaporators 16 and 17 before finally flowing back to the equipment to be cooled via pipe 5. The required amount of cooling of the liquid in the evaporators is obtained when the methyl alcohol is subjected to a pressure of 700 gm. per sq. cm. equivalent to an altitude of 3000 metres. When the aircraft rises above this altitude regulator 32 acts as an exhaust valve for both evaporators and restores the pressure in the evaporators to 700 gm. per sq. cm. via stacks 26 and 27 and valve 31. When the aircraft descends below 3000 metres the regulator 32 is set directly in communication with the atmosphere and the methyl alcohol in evaporator 16 boils off at a higher temperature and does not sufficiently cool the liquid. The evaporator 17 however is subjected to a depression through regulator 33 which communicates with extractor 35 which restores inside evaporator 17 a pressure of 700 gm. per sq. cm. Valve 31 remains closed while extractor 35 is in operation.