Wick assembly for self-regulated fluid management in a pumped two-phase heat transfer system

摘要

A two-phase closed-loop heat transfer system comprises a capillary-type evaporator 10, a condenser 11 (preferably also of the capillary-type), and a vapor conduit 17 through which heat-laden working fluid in vapor phase is driven adiabatically from the evaporator 10 to the condenser 11. The evaporator 10 comprises a plurality of tubes 12 connected in parallel. A helically threaded capillary channel 39 is formed on the cylindrical interior surface of each tube 12, and a wick assembly 33 is positioned longitudinally within each tube 12. Each wick assembly 33 comprises a high-permeability wick 36 within which are embedded a first tubule 34 and a second tubule 35. The first and second tubules 34 and 35 are of low permeability, and have one closed end and one open end. The open end of the first tubule 34 is connected to a feed line 16 through which liquid-phase working fluid is delivered into the first tubule 34. Liquid-phase working fluid seeps through the first tubule 34 into the surrounding wick 36, and migrates through the wick 36 to the capillary channel 39 with which the wick 36 is in contact. Liquid-phase working fluid in excess of an amount needed to keep the capillary channel 39 wetted seeps from the wick 36 into the interior of the second tubule 35. The open end of the second tubule 35 is connected to a return line 18. The condenser 11 is connected to a condensate line 23 through which working fluid that has condensed to liquid phase is withdrawn. The return line 18 and the condensate line 23 merge into a coadunate conduit 24, which is connected to an inlet port of a pump 26. The pump 26 provides sufficient suction pressure to withdraw liquid-phase working fluid out of the condenser 11 that has formed therein by condensation, and to withdraw liquid-phase working fluid out of the evaporator tubes 12 that is in excess of the amount needed to keep the capillary channels 39 in the tubes 12 continuously wetted. The pump 26 recirculates the liquid-phase working fluid via the feed line 16 to the evaporator 10.