A new model for calculating effective thermal conductivities of different metal foams is proposed based on an appropriate geometrical modeling method. The geometrical modeling is based on the representative cell geometry of metal foam

Kelvin tetrakaidecahedron

and the foam ligament is geometrically represented by concave tri-prism. The characteristic of foam node is also taken into account in the model. A general expression for calculating effective thermal conductivity is derived from thermal resistance analysis. In the present model

no geometrical parameter needs to be determined through experiments to describe the relationship between foam ligament and node. Compared with available experimental data and semi-empirical models in literature

the present model can accurately predict the effective thermal conductivities of different metal foams saturated with different mediums

with the average relative deviations from the experimental data within 10%. Considering both accuracy and generality

the present model is superior to existing semi-empirical models.