Effective thermal conductivity and permeability of aluminum foam materials

An experimental measurement program was performed to determine thermo-physical properties of aluminum-based foam metals. The effective thermal conductivity k(e) and permeability K were investigated in detail. Experimental facilities were fabricated, and the measurement procedures and methodologies were evaluated. One-dimensional heat conduction was considered to determine k(e). The results indicate that k(e) increases as the porosity epsilon decreases. However, no noticeable changes in k(e) were detected from variations of the cell size of the foam metal at a fixed porosity epsilon. The permeability K is substantially affected by both epsilon and the cell size. An empirical correlation for the friction factor f is proposed based on the concepts of K and inertial effect.