Natural convection through an annular vertical cylindrical porous medium

摘要

Heat transfer by natural convection through a vertical annular cylinder filled with porous media is investigated. The temperature at the inner surface of annular cylinder is assumed to vary according to power law, along the height of the cylinder. The outer surface is exposed to ambient temperature. The flow inside the porous medium is assumed to be Darcy flow. The governing partial differential equations are non-dimensionalised and solved by using finite element method. Effect of aspect ratio and radius ratio on the heat transfer behavior is analysed. Results are presented for various values of Rayleigh number and power law exponent. It is seen that the average Nusselt number decreases with increase in power law exponent.