TiO ₂-water nanofluid within a tilted triangular enclosure including a square heater: Optimum heat transfer

Into this paper, natural convection of TiO₂-water nanofluid is numerically investigated around a square isothermal heater, found into a two-dimensional cold enclosure of an isosceles triangle form. To do so, a computer code based on the finite volume method and the velocity-pressure correction approach, namely SIMPLER, is used. This code has been validated for cases of a base fluid and a Nanofluid, after comparison between the obtained results and the numerical (or experimental) ones already available in the literature. To make clear the effect of main parameters such the Rayleigh number, the solid volume fraction as well as the cavity' inclination angle, the convection phenomenon is reported by means of Streamlines and isotherm plots; with a special attention to the Nusselt number evolution. The results show that the mean Nusselt number is an increasing function of the Rayleigh number and the solid volume fraction, whereas the inclination angle of the cavity has no significant effect on heat transfer. Then, useful correlations which predicting the latter as a function of the solid volume fraction for various Rayleigh values are proposed, which predicts within ±0.4% the numerical results.