Turbulent heat transfer enhancement in an air-to-water heat exchanger

Abstract

Hydrothermal behavior in a water-to-air double-pipe heat exchanger is studied experimentally and numerically. To achieve fully developed conditions, the heat exchanger was built with additional lengths before and after the test section. Commercial code (ANSYS 14) is used for numerical section. In order to enhance rate of heat transfer, discontinuous helical fins is utilized. Results show that Nusselt number augments with the enhancement of Reynolds number and Prandtl number, which are calculated at bulk temperature. The use of square section helical fins also shows a higher heat transfer enhancement rate than that of the circular one. Thermal performance factor is an increasing function of the open area ratio.