Resumo:
A theoretical study of laminar and turbulent flow with heat transfer by forced, natural, and mixed
convections is performed in this work using the finite volume method to approximate solutions
to some different domains and, therefore, a few computational codes are developed in order to do
that. When forced convection problems are concerned, the following situations are analyzed:
laminar and turbulent convection in straight and U-shaped channels, both with and without
restrictions. As for natural convection problems, the ones considered are: turbulent flow in
rectangular cavities with the left, right, and horizontal walls being heated, cooled, and isolated,
respectively. Some other geometries involving natural convection are studied such as triangular
cavities submitted to many boundary conditions and a rectangular cavity with an internal heated
cylinder and an upper surface with convection to the environment. In addition to the previous
cases, there are still the mixed convection ones that are: square cavities with an upper inlet
opening on the left vertical surface and a lower outlet opening on the right wall. These vertical
surfaces with the openings are isothermal whereas the horizontal ones are adiabatic. The
conservation equations are discretized through the finite volume method. The turbulence models
which are implemented are: k-ω model and the sub-grid model (Smagorinsky model,
Smagorinsky model with buoyancy terms, vorticity transfer theory model, and the sub-grid and
velocity structure function model). Local and average Nusselt numbers are calculated for all the
cases mentioned previously.
