TRANSIENT CONJUGATED FORCED-CONVECTION IN A PARALLEL-PLATE DUCT WITH CONVECTION FROM THE AMBIENT AND PERIODIC VARIATION OF INLET TEMPERATURE

This work shows an approximate analytical solution for the heat transfer problem of transient laminar forced convection valid for the thermal entrance region of a parallel plate duct, with walls interacting with an ambient medium outside the duct. The inlet temperature varies periodically with time and duct wall thermal capacity is considered finite. Periodic solutions, obtained by using Laplace transform, are presented for the duct wall temperature, fluid bulk temperature and wall heat flux as a function of the axial position and of the involved parameters.