Determination of vapor bubble diameter of fc3284, fc84 and their binary mixtures during pool boiling

Abstract

The bubble diameter of FC3284, FC84 and their mixtures during pool boiling were measured with a dual-probe which was located at a certain distance from the heating surface. In this study, temperature controlled heating surface was used. The difference between heating surface and saturation temperatures was increased gradually to obtain entire pool boiling regions at atmospheric pressure. Along the entire boiling curve, vapor bubble diameter was determined at that specified point. First of all, bubble diameter was determined for pure substances and their binary mixtures respectively. Different bubble diameters were determined in the different pool boiling regions. The results were compared with each other and with existing correlations in literature. It was found out that surface tension, viscosity and wall superheat are important factors which may affect the bubble departure diameter. At the beginning of the nucleate boiling, the results were in agreement with some related correlations in the literature and bubble diameters for pure substances FC3284 and FC84 were lower when compared to that of their binary mixtures.