Effect of fin geometry on the performance of tubular-fin heat exchangers: A computational fluid dynamics study

Tubular-Fin heat exchangers are a type of compact heat exchangers with prominent features like high levels of exchanged heat and less space occupancy. These heat exchangers are commonly used for exchanging heat between gas and liquid. In this study, for a tubular-fin heat exchanger, the heat transfer and pressure drop for circular and serrated fins with the triangular arrangement are numerically calculated and compared with the existing experimental data. A three-dimensional numerical study with the Reynolds mean-averaged Navier-Stokes (k-ε) model for turbulence is conducted. In the Reynolds range of 6000 to 25000, the performance of four types of fin geometry (serrated, semi-serrated, circular and semi-circular) are compared. The results show that the circular fin has the highest heat transfer rate, while the serrated fin has the highest reduction in the gas temperature. It is also found that the semi-circular fin has the highest thermal enhancement factor and the semi-serrated fin has the highest heat transfer coefficient. The results of the present study can be beneficial in the selection of optimal fins in a heat exchanger from both practical and economic aspects.