Abstract:
We present in this thesis a study of laminar natural convection and entropy
generation in a square cavity filled with a nanofluid. The two vertical walls of the cavity
are maintained at hot and cold temperatures, and the horizontal walls are thermally
insulated. The governing equations of the phenomenon in question are solved by the
finite volume method. A FORTRAN computer code has been developed to calculate the
flow and thermal fields, average and local Nusselt numbers, and entropy generation.
Effects of Rayleigh number, solid volume fraction of nanoparticles, length of the heat
source, type of nanofluids, conductor (fin), its position and thermal conductivity, and
thickness of the bottom wall of the cavity, on the flow and thermal fields, and on
average Nusselt number, entropy generation and Bejan number are presented. Results
show that the heat transfer by natural convection is more important in a nanofluid than
in the basic fluid (water), but the entropy generation is less important.
Finally, an experimental study of natural laminar convection in a cubic cavity filled
with pure water is presented.
