MIXED CONVECTION ON A HORIZONTAL PLATE WITH UNIFORM SURFACE HEAT FLUX.

The effects of buoyancy-induced streamwise pressure gradients on laminar forced convection over a horizontal flat plate with uniform surface heat flux are studied analytically by the local similarity and local nonsimilarity methods of solution. Numerical results for the local surface heat transfer, wall shear stress, and velocity and temperature distributions are presented for a Prandtl number of 0. 7 and for aiding flow with buoyancy force parameter Gr//x*/Re//x**3 ranging from 0 to 1. 0. It is found that both the local Nusselt number and the local friction factor increase with increasing buoyancy forces. In addition, the buoyancy-affected velocity profiles exhibit an overshoot beyond the free stream velocity. With regard to the heat transfer results, significant buoyancy force effects were encountered for Gr//x*/Re//x**3 greater than 0. 025. A comparison between the present results with those for the case of uniform wall temperature shows that heating by uniform surface heat flux provides considerably higher surface heat transfer rates than heating by uniform wall temperature.