Condensation heat transfer on pin-fin tubes: Effect of thermal conductivity and pin height

New experimental data are reported for condensation of ethylene glycol and R-113 at near atmospheric pressure and low velocity on three identical pairs of pin-fin tubes made of copper, brass and bronze. The only geometric parameter varied was pin height. For both fluids tested, copper pin-fin tubes showed the highest gain in heat-transfer enhancement ratio with increasing pin height. Vapour-side, heat-transfer enhancement ratio was relatively weakly dependent on tube thermal conductivity for R-113 and more strongly dependant in the case of ethylene glycol. Data showed a strong heat-transfer enhancement dependence on unflooded area enhancement.