In this work, drying of a rigid capillary porous medium is considered, i.e. of a porous medium in which the pore size is typically in the micrometer range. When modeling the drying process in such a medium by the one-equation continuum model, conventionally it is assumed that the vapor is in local equilibrium with the liquid both inside the porous medium and at the evaporative surface. However, the validity of this assumption has not been proven yet. This will be investigated here with the help of pore network drying simulations. Because of the importance of the evaporative surface, special focus will be set on the change of the degree of local equilibrium at the surface with the variation of operational conditions of the drying process, geometrical characteristics of the network and liquid transport mechanisms.weiterlesen