Diffusion Models for Fractured Media

Two models for diffusion in fractured media are described; the compartment model as an example of a double-porosity system, and the micro-structure model as the limit by homogenization of local flux-coupled classical diffusion models which depend on the geometry. These two models are shown to be examples of a single evolution equation for which the appropriate initial-boundary-value problems are well-posed. This gives a unified theoretical basis for these two (as well as classical diffusion) models in which they can be compared and studied. cc 1990