For the efficient design of serpentine type heat exchanger, the influence of heat conduction between tubes(inter-conduction) through the fin is numerically investigated. The performance of the heat exchanger is analyzed by a differential method considering the heat transfer in fin as composed of inter-conduction and convection to the flowing air. The effect of perforation of middle part of fin is investigated to reduce the effect of inter-conduction by calculating the effective conduction length. The effect of fin addition to the end-side tubes is also investigated. Numerically simulated results of these effects are fitted into proper functions. The effectiveness of serpentine type heat exchanger is enhanced by reducing the inter-conduction of fin and by adding fin on the end-side tubes.
