Modeling of Heat Transfer by Laminar Natural Convection of a nanofluid in a Solar Water Heater Enclosure

Abstract

We numerically study the laminar natural convection of a water copper nanofluid in a solar water heater enclosure with heating through the solar collector wall being at constant temperature Tc. This solar collector is connected with a solar thermal storage tank having a rectangular form with the vertical wall left cold at constant temperature Tf while the unheated parts of the enclosure (solar water heater) were considered adiabatic. For the purpose of analyzing the effect of the use of a nanofluid on heat transfer by natural convection, the volume fraction of the particles is varied in the range of 0 to 0.25. The permanent forms of the Navier-Stokes equations in two dimensions and the conservation equations of mass and energy were solved by the finite volume method. The SIMPLE algorithm was used to allow pressure-velocity coupling. The Rayleigh number Ra was varied in the range 103-106