Pore surface energy corrected P-α like models and the anomalous behaviour of porous materials

Accurate models for the description of porous materials are necessary in simulations of collisions between pre-planetesimals which are required to study the viability of collisional growth as a mechanism leading to the formation of planetesimals. We have compared two porosity models that have been used in the related field of impact cratering, and we have found that they suffer two problems when applied to high porosity materials that are likely to show the so called anomalous behaviour. To overcome the observed problems we have proposed a correction of the internal energy of the porous material considering the contribution of the surface energy of the pores.