In this paper the authors numerically investigate dynamic heat transfer in porous and partially porous cavities, paying particular attention to the dependence of velocity and temperature fields on Rayleigh (Ra) number, porous layer permeability, and cavity aspect ratio (AR). Heat and fluid flow are described by using the generalized porous medium model and the governing equations have been numerically solved using the Artificial Compressibility (AC) version of the Characteristic Based Split (CBS) scheme.