XX Fluid Mechanics Conference KKMP2012, Gliwice, 17-20 September 2012 VISCOUS FLOWS ACROSS CERAMIC FOAMS – A NUMERICAL AND EXPERIMANTAL STUDY Wojciech REGULSKI 1 , Konrad GUMOWSKI 1 , Łukasz ŁANIEWSKI-WOŁŁK 1 , Jakub SKIBIŃSKI 2, Tomasz BARCZAK 1 1 Institute oa Aeronautics and Applied Mechanics, Warsaw University of Technoogy, Warsaw, Poland 2 Faculty of Materials Engineering, Warsaw University of Technoogy, Warsaw, Poland E-mail: wregulski@meil.pw.edu.pl Key words: porous media, pressure drop The industrial importance of structures with open porosity such as ceramic or metallic foams has been growing over recent years. Their specific properties such as remarkably huge specific surface area, high porosity, low density, mechanical, thermal and corrosion resistance outperform other materials and predestine them to serve as compact heat exchangers, reaction catalysts, flow stabilizers or filters. This results in an increased demand for accurate hydrodynamic properties (such as pressure drop) in these materials without a priori knowledge of flow characteristics[1]. The simplest relation between the pressure drop and flow’s bulk velocity has the form of the Darcy-Forchheimer equation that links the pressure gradient to viscous and inertial drag of the medium: 2 1      p u Cu L K (1) With K as the so-called permeability and C being an arbitrary constant. Fig. 1 –CT images of ceramic foams: 10ppi, 20ppi and 30ppi foams respectively. In recent years simplified regular models of porous materials were proposed and accurate yet concise relations for the pressure drop in the flows across such geometries were given[2]. These correlations contain the coefficients K and C that are only pore-geometry dependent and involve the pore size, a, strut diameter, d s , specific surface area, a c , and porosity, ε. They, however, do not involve the effect of the pore blockage, which has little