Characterization of Air Flow Through Sintered Metal Foams

Abstract

This study investigates air flow in metallic foams, which are produced by the slip reaction foam sintering (SRFS) process. It was conducted as part of the collaborative research center (SFB) 561 “Thermally Highly Loaded, Porous and Cooled Multi-Layer Systems for Combined Cycle Power Plants.” The flow through a porous medium is analyzed by Darcy’s equation with the Dupuit/Forchheimer extension. All measurements can be described very well by this equation and permeability and inertial coefficients are obtained for a large quantity of samples with different base materials and different porosities. A threshold porosity of 70% is observed, above which the pressure loss significantly starts sinking with porosity. Additionally, it was found that the permeability was anisotropic. Permeability is lower in the direction of gravity during foaming. Scattering in the data of the permeability and inertial coefficients versus the porosity is observed and discussed.