R. Kumar et al., Augmentation of heat transfer during filmwise condensation of steam and R-134a over single horizontal finned tubes, INT J HEAT, 45(1), 2002, pp. 201-211
An experimental investigation has been carried out to augment the heat tran
sfer rate by enhancing the heat transfer coefficient during the condensatio
n of pure vapours of steam and R-134a over horizontal finned tubes. The stu
dy was conducted for plain tubes, circular integral-fin tubes (CIFTs), spin
e integral-fin tubes (SIFTS) and parially spined circular integral-fin tube
s (PCIFTs). The SIFT out performed the LIFT for the condensation of R-134a
by approximately 16%. However, the spines were found most effective in the
bottom side of the LIFT. The PCIFTs with the spines only in the bottom side
of the tube augmented the heat transfer coefficient by 20% and 11% for the
condensation of steam and R-134a, respectively, in comparison to the LIFT.
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