Fluid flow modelling techniques

The porous medium is characterized by the manner in which voids are embedded, their interconnectivity, size and shape. Usually, depending on the lattice structure, all natural and artificial materials can be divided into four main categories as follows: (a) porous, (b) non-porous, (c) fractured and (d) combination of fractured and porous media ( Fig. 5.1 ). Various theories have been developed for each application depending on how flow takes place through a porous or fractured media, or a combination of both. For example, in soil science, flow is usually modelled using a porous medium approach. It is usual practice to simulate flow through fractured media, such as in fractured rock media, using modified theories developed for fluid flow through pipes or channels. The selection criterion for type of flow analysis depends on the availability and extent of field data, computer resources and the degree of the accuracy required for the particular application. The available rock mass properties and the geology of the area also influence the initial adoption of the methodology. Techniques of flow analysis technique can be grouped as either one or more of the following: Continuum approach - for porous media; Discrete fracture flow theory - fractured media; and Dual-porosity method - coupled porous and fractured media.