Three-dimensional Numerical Study of the Effect of Heating Sources Dimension on Natural Convection in a Cavity Submitted to Constant Heat Flux

摘要

Natural convection in a cubical cavity, discretely heated is studied numerically using a three-dimensional finite volume formulation. Two heating square portions are placed on the vertical wall of the enclosure, while the rest of the considered wall is adiabatic. The opposite vertical wall is maintained at a cold uniform temperature and the other walls are adiabatic. Effects of the heating sections dimensions ε (0.15 ≤ ε ≤ 0.35) and the Rayleigh number Ra (10~3 ≤ Ra ≤ 10~7) on the fluid flow and the heat transfer within the cavity are studied. The obtained results show that the flow intensity and the heat transfer can be significantly improved by an optimal choice of the governing parameters. Streamlines, isotherms and variations of the average Nusselt number are shown for different sets of the considered parameters.