Computational aspects of effective thermal conductivity of highly porous metal foams

A resistor model has been presented for easy estimation of effective thermal conductivity (ETC) of highly porous metal foams based on experimental data available. Recently, Calmidi and Mahajan [ASME J. Heat Transfer 121 (1999) 466] and Boomsma and Poulikakos [Int. J. Heat Mass Transfer 44 (2001) 827] have presented geometrical models for highly porous metal foams. However, our approach is based on numerical simulations in which ETC of a random two-phase medium is being comprised of contributions from both the phases. To take account of highly conducting phase, non-linear flow of heat flux lines and random distribution of the phases, a correlation term F is introduced. An effort is being made to correlate the values of F estimated numerically, in terms of ratios of thermal conductivity of the constituent phases and the porosity of the matrix. Best fitted relation for F is presented here. A very good agreement is observed between estimated results with experimental data available in the literature [Int. J. Heat Mass Transfer 45 (2002) 1017]. Comparison of the proposed relation with different models [Int. J. Heat Mass Transfer 44 (2001) 827, Int. J. Heat Mass Transfer 45 (2002) 1017] has also been made.