In this publication experimental results for the axial two-phase thermal conductivity of different ceramic sponges (variation of material, porosity and pore size) are presented, revealing a strong influence of the superficial air velocity and of the porosity of the ceramic sponges on the axial two-phase thermal conductivity. The experimental data are correlated in dimensionless form to offer a "universal" equation for calculating the axial two-phase thermal conductivity of sponges in the future. (C) 2011 Elsevier Ltd. All rights reserved.