Surface Area and Conductivity of Open-Cell Carbon Foams

Abstract

High thermal conductivity carbon foams have recently emerged as an effective thermal management material for space applications due to their lightweight. Open cell carbon foams are generally processed from pitch material obtained from coal or petroleum. These foams have spherical pores that create a three dimensional network of ligaments and nodes of complex geometry. The thermal conductivity of carbon foams can be studied numerically by finite element method; however the analysis requires a very fine grid that captures the microstructure of the foam. In this work, an analytical model for surface area and thermal conductivity is developed for a foam. To reduce the computational effort, an electrical circuit network analogy is used to calculate the bulk thermal conductivity of the foam. The analytical solution is then compared with semi-empirical models, FEM solution and other analytical solutions.