Natural convection in a square enclosure filled with a
porous matrix is performed numerically by using the finite volume
method. Three discrete heat sources are mounted at the top and the
left and right sidewalls of the enclosure. The bottom wall is
considered adiabatic while all the other walls are maintained at a
cold temperature except at the heat source locations which are kept
at a hot one. The length of the discrete heat source at the top wall is
double than the heat sources at the sidewalls. From the other hand,
the heat source at the top wall is considered fixed while the other
heat sources are moving at five different locations. The influence
of the Rayleigh, Prandtl, Darcy numbers and the heat source
location on the flow and thermal fields are investigated. The
considered parameters are Darcy number [Da = 10-3-10-5],
Rayleigh number [Ra =103-106] and Prandtl number [Pr = 0.7, 6
and 1000]. It is found that the average Nusselt number increases
for different heat source locations when both Rayleigh and Darcy
numbers are high. Also, it is recommended to use the heat source
location suggested in case (5) where a higher flow circulation is
observed.