Combined free convection and forced convection in a square enclosure with a
finite-size heat source is studied numerically. A square heat-conducting b
ody is located somewhere within the enclosure. The present study simulates
a practical system, such as an air-cooled electronic equipment with heat co
mponents or an oven with heaters. Emphasis is placed on the influences of t
he configurations and physical properties of the enclosure. The developed m
athematical model is governed by the coupled equations of stream function,
vorticity transport, and energy, and is solved by employing the cubic splin
e collocation method. The computation is carried out for wide ranges of Rey
nolds and Grashof numbers. The results indicate that both the heat transfer
coefficient and the dimensionless temperature in the body center strongly
depend on the configurations of the system studied, such as size, location,
and thermal conductivity of the conducting body and the location of the ou
tflow opening. Detailed results of the interaction between forced airstream
and the bouyancy-driven flow by the heat source are demonstrated by the di
stributions of the isotherms and streamlines and the variations of the heat
transfer coefficient.