Numerical Investigation of a 5 Kw Power Porous Medium Burner

Abstract

It is most important that a fuel be burnt in a way with least possible pollution to the environment. In this regard every day new legislation is passed restricting pollutant gas emission. A second important issue is to obtain high-density thermal energy via enhanced volumetric heat release. Porous media combustion offers solutions that address both these issues. In this study, we performed several numerical analyses of a symmetrical two-dimensional problem to investigate combustion within a 5 kW porous burner and thermal efficacy of our design. Solution domain consists of four sub-domains, two porous regions in tandem (first with low porosity and second with high porosity), a water tank with constant flow rate and a solid wall in between those. Methane-air is used as reactant mixture for combustion with different excess air ratios and as a parametric study, various water flow velocities are tested for each excess air ratio. Navier-Stokes, energy (thermal equilibrium model) and species transport equations are solved in two-dimensional symmetrical model. A two-step global methane oxidation mechanism is utilized. Velocities, temperature distributions in both combustion zone and water tank, temperature distribution in the axial direction at the centerline of the combustion zone and heat transfer from combustion zone to water are presented.