하이드로카본 냉매의 풀비등 열전달 상관식 개발

In this work, pool boiling heat transfer coefficients(HTCs) of hydrocarbon refrigerants are measured from a horizontal smooth tube. Tested pure and mixture refrigerants are Propane, Propylene, Isobutane, Butane, DME and Propane/Isobutane. The compositions of mixtures were 25%, 50%, 75% of propane respectively. The pool temperature was maintained at saturation temperature of 7℃ and heat flux was varied from 10 ㎾/㎡ to 80 ㎾/㎡ with an interval of 10 ㎾/㎡. Wall temperatures were measured directly by thermocouple hole of 0.5 ㎜ od, 152 ㎜ long and inserting ungrounded sheathed thermocouples from the side of the tube. Tested results show that HTCs of Propane, Propylene are 2.5%, 10.4% higher than those of R22 while those of Butane and Isobutane are 55.2%, 44.3% lower than those of R22 respectively. For pure refrigerants, new correlation can be applied to all of CFCs, HCFCs, HFCs, as well as hydrocarbons was developed. For mixture refrigerants, new correlation instead of Ko et al.'s pure refrigerants correlation was applied to An et al.'s mixture refrigerants correlation. The result was that mean deviation was 4.2% for hydrocarbon mixture and 7.16% for all refrigerants.