Modeling of coupled conduction and convection in moist air cooling

This article deals with the numerical simulation of moist air cooling in compact heat exchangers. The model requires the solution of a coupled problem, since interface temperatures must be calculated at the same time as temperature distributions in adjacent fluid and solid regions. The energy equation is solved in the whole domain, including the solid region, and the latent heat flux on the surfaces where condensation occurs is taken into account by means of an additional internal boundary condition. The approach is completely general, even if the finite-element method is used in the calculations. The accuracy, reliability, and capabilities of the methodology are demonstrated by examples of application concerning heat exchangers of both the plate-fin and the tube-fin types.