DNS and RANS simulations of a coil heat exchanger immersed in a tank

Abstract

The operation of heat exchangers in a thermal system can be described by simple heat transfer equations. The heat exchange is normally defined by a global heat transfer coefficient, which takes into account internal and external convection and the characteristics of the pipe. This coefficient can be obtained analytically only for heat exchangers with standard and simple geometric characteristics otherwise leading to unacceptable inaccuracies when employed in lower-order models. An effective solution for calculating the global heat transfer coefficient for a particular heat exchanger consists of the full simulation of the heat exchange, including internal pipes and external fluid, through CFD&HT simulations. In this work, simulations of a coil heat exchanger are carried out, and the values obtained are compared with those of a reference work obtained experimentally [1]. In this work, the results obtained by means of different turbulence models present in the OpenFOAM software are compared.