AUGMENTATION OF THERMAL COEFFICIENTS DURING THE CONDENSATION OF ORGANIC VAPOURS ON MILD STEEL SUBSTRATES.

In this investigation, a very thin coating (14 mu m) of Teflon was registered on a mild steel surface with a view to preventing its wettability by organic vapours. Out of the 33 organic vapours tested for their pattern, only 13 showed promise for enhancement of heat transfer rates. Out of these, four vapours tested for their pattern, only 13 showed promise for enhancement of heat transfer rates. Out of these, four vapours were subjected to endurance tests, to confirm the permanancy of patterns of their condensation and for aquisition of heat transfer data. Later, five vapours were chosen, for quantitative study of parametric effects. Augmentation over filmwise condensation of 1. 33-8. 8 times for the vapour side coefficients and 1. 13-1. 44 times for the overall coefficients, respectively, was obtained.