CFD simulation of heat transfer in a circular channel: effect of the Pe number

The numerical investigation of interphase heat transfer in a circular channel under laminar flow regime at different values of the Pe number is performed by means of a 2D mathematical axisymmetric model in which energy equations are coupled to the Navier-Stokes equations. The constant wall heat flux and constant wall temperature cases are simulated at different values of the Pe number. Results show that the heat transfer efficiency in both cases is strongly influenced by the back-diffusion even at very high values of Pe (Pe > 700). This behaviour is shown to be the result of the coupling between the interphase heat transport phenomena and the fluid flow. New correlations are hence derived to take into account the effect of back-diffusion on heat transfer.