HEAT TRANSFER IN TWO-PHASE CLOSED-TYPE THERMOSYPHONS.

Abstract

An experimental study on the heat transfer in a closed-type thermosyphon in which boiling and condensation occurred was performed to investigate its heat transfer characteristics. In two test tubes of different length, water and ethanol were used as working liquids, and the effects of the tube length, heat flux, operating pressure (or corresponding saturation temperature), ratio of heated to cooled length and quantity liquid, on the heat transfer coefficients were examined. As a result, the optimum quantity of liquid was found to be 10 to 20 percent of the inside tube volume.