Simulated condensation has been conducted on three wire wrapped tubes having
same root diameter but different fin spacing of 1.5mm, 2mm and 2.5mm.
Different fluids (Ethanol, Ethylene Glycol and Water) are used for
condensation by providing them to the tubes through tiny holes in inter-fin
spacing on the top of the surface of tubes. The major parameters are to be
controlled in this research are fin spacing, vapor velocity, condensate flow
rate and ratio of surface tension to density of the fluid. Obtained results
show that flooding angle (calculated from the top of the tube to the level
where fluid fills the fin) rises by increasing fin spacing. Also, retention
angles increase by reducing ratio of surface tension to density of fluid.
Acute flooding angles at zero air velocity and zero flow rate, elevates by
increasing air velocity. However, obtuse flooding angles at static
conditions drop by reducing air velocity. An interesting result is obtained
regarding retention angle which remains almost even for the higher
condensation flow rates until the tube gets inundated with condensation.
Moreover, critical flow rates for all the tubes against using different
working fluids are measured. Results obtained for static conditions have
good correspondence with already available authentic data for flooding
angle. Pictures showing condensate retention angles have been included in
this paper.