COMBINED FORCED AND FREE LAMINAR CONVECTIVE HEAT-TRANSFER FROM A VERTICAL PLATE WITH COUPLING OF DISCONTINUOUS SURFACE HEATING

Combined free and forced laminar air convective heat transfer from a vertical composite plate with isolated discontinuous surface heating elements has been studied numerically and experimentally. The problem has been simplified by neglecting heat conduction in unheated elements of the plate to accomplish a better understanding of the complicated combined/complicated convection problem. In this study, it is most important in explaining the heat transfer behaviour to clarify the interactions between buoyancy and inertia forces in the convective field and also the coupling effects of unheated elements upon the combined flow fields. Therefore, the temperature distributions of the wall surface and local Nusselt number, obtained by numerical calculations and experiments, have been discussed based on the various parameters associated with the present convection problem, i.e., Grashof number Gr(L), Reynolds number Re-L, geometry factor D/L and stage number N. Heat transfer characteristics Nu(t)/Re-L(1/2) of this combined and coupled convection of air are presented as a function of a generalized coupling dimensionless number Gr(L)/Re-L(2), and stage number N for certain values of the geometry factor of D/L.