Abstract
In this study, we carried out experiments or three types or low-tinned tubes and externallv microscopic-grooved tubes using two fluorocarbon refrigerants: R123, which has a small ozone depletion potential (ODP); and R245fa, which has a zero ODP and a global-warming potential smaller than that of R134a. Both refrigerants are currently used in shell-and-tube condensers of turbo-refrigerators. The verified results, which are fundamental performances of condensation heat transfer, flow pattern of condensation liquid film, heat transfer enhancement effects and other related factors experimentally for those tubes and refrigerants, were reported in this paper.
