Optimized shape design and thermal characteristics investigation of helically coiled tube type heat exchanger

Abstract

The effects of the helical coil tube designs on heat transfer characteristics during heating process were conducted by some researchers and confirmed that the conventional helical coil tube was not the ideal shape for important heat transfer. Despite this, there was no published paper that presented the optimal helical coil structure for important heat transfer. Therefore, this work addresses the influence of different helical coil structure designs on heat transfer characteristics and temperature distribution during heating process. The study was performed for three configurations named constant-diameter coil, variable-diameter coil and variable-pitch coil. Based on CFD simulation, the mathematical model was validated with experimental results and show good agreement. The results suggest that the helical coil with variable-pitch gives the best heat transfer performance compared with other helical coil structure. Among all considered designs, the combined properties of the helical coil with variable-pitch were better than that of other helical coil structures. As a result, this work could provide a shortcut method in the selection of the appropriate helical coil immersed or wrapped on the tank which need the high heat transfer.