Effect of the days scrolling on the natural convection in an open ended storage silo

Abstract

Paper presented at the 7th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Turkey, 19-21 July, 2010.The problem of unsteady natural convection heat transfer in a vertical open ended porous cylinder heated with a sinusoidal time variation of the lateral wall temperature has been investigated numerically The used flow model is the classical Darcy model. In the case of constant wall temperature two types of flows, with and without fluid recirculation, depending on the filtration Rayleigh (Ra), the aspect ratio (A) and the inlet-outlet conditions (Bi) have been obtained. For the low dimensionless amplitudes case (XA<0.5), a large equivalence in the heat transfer between the sinusoidal time variation and the constant wall temperature is demonstrated with a difference is less than 5%. For high Ra, the difference increases.