Numerical study of heat transfer in a finned double pipe heat exchanger

Abstract

In the present study the performance of a concentric tube heat exchanger is analyzed with passive heat transfer technique. The performance of the heat transfer process in a given heat exchanger is determined for three different longitudinal fin profiles, rectangular, triangular and parabolic. Numerical analysis was carried out in a parallel flow double pipe heat exchanger for the above profiles for varied mass flow conditions both in the inner and outer tube. Base width and height of the fin were kept constant for all the three types. Simulated results indicated an enhancement in the heat transfer rate for a finned tube compared to the unfinned one. Among the different configurations, fin with rectangular profile showed marginal improvement over triangular and concave parabolic profiles in terms of heat transfer characteristics. For a constant value of mcc = 0.02kg/s and varying mch, rectangular finned tubes showed an average improvement of 6.1% over the triangular and 9.2% over parabolic finned tube. Similarly For a constant value of mch = 0.02kg/s and varying mcc, it showed an improvement by 2 and 5% over the triangular tube and parabolic finned tube respectively Fins with concave parabolic profiles exhibited minimum pressure drop and has reduced by 38% and 65% compared to the triangular and rectangular finned tube