Experimental study of a finned-tubes coil with wet wall conditions

Experimental study of a finned-tubes coil with wet wall conditions. The use of a global pseudo-conductance in the mathematical model of heat and mass transfer within a heat exchanger allowed us to take into account the water condensate on the wall as well as air humidity. The application of this dua l consideration to our experimental investigation shows a "critical" Reynol ds number at which we observe an inversion of the thermal behavior. The hea t exchanger considered in this work has been used in a previous published w ork where heat transfer occured only with dry wall condition. (C) 2001 Edit ions scientifiques et medicales Elsevier SAS.