In this paper we study by numerical simulation, the cooling of a solar cell by forced convection in the presence of a nanofluid. The inclined walls of the cavity are adiabatic but the silicon solar cells are subjected to a constant heat temperature. The nanofluid is introduced into the cavity with a constant vertical speed and subjected to room temperature. The equations governing the flow hydrodynamics and heat transfer are described by the Navier-Stockes and energy equations. For the physical parameters of Al2O3-Water nanofluid, we use the model of Brinkman and Wasp. The finite elements method is used to solve the system of differential equations that is based on the Galerkin method. We consider the effect of solid volume fraction for different