Si-SiC open cell foams with porosity .87% and high pore sizes (4-7 mm) are commonly employed as active zone in porous burners for heat radiation applications. In a porous burner, the solid porous body let the heat recirculate from the hot combustion products to the incoming reactants. The result is that the flame is confined within the foam, meaning high thermomechanical loadings on its constituent material. A set of commercial Si-SiC foams from the same production batch was aged with flat porous burners. Thermal cycles ramp-up, dwell and cooling, as well as burner set-up (power: 15 kW, fuel/air ratio: 1?5), were chosen based on previous experience. Before aging, each foam was first cut in bars ready for bending tests, reassembled into the burner foam configuration and operated. As produced and aged samples were physically, mechanically and chemically analysed and results compared.
Ceramic foams are used in thermal application both as insulations and heat exchangers. Understanding the effect of foam morphology on their effective thermal conductivity is important for design engineers. In this work, the effects of parameters such as: porosity, cell inclination angle and ligament tapering are studied using Finite Elements (FE) method. For the purpose, an algorithm for the generation and meshing of tetrakaydecahedra was implemented and steady state thermal simulations performed. Results compared with experimental data from the literature showed good agreement. A strong decrease of thermal conductivity was found by increasing porosity and ligament tapering, while a less significant increase was noticed on increasing cell inclination angle.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.