Discrete Particle Simulation of Granular Flow

Granular materials, which can be either wet or dry and range from nanometers to centimetres in size, are widely encountered in industries and in nature. As with solids, they can withstand deformation and form heaps; as with liquids, they can flow; as with gases, they exhibit compressibility. These features give rise to another state of matter that is poorly understood (Ennis et al., 1994; Jaeger, et al., 1996; de Gennes, 1999). This can be highlighted from the study of granular flow which, corresponding to the fluidand solid-like modes, has different flow regimes such as quasi-static regime, rapid flow regime and a transitional regime that lies in between. Development of a general theory to describe granular flow has been a challenging problem in the scientific community for years (see, for example, Edwards and Grinev, 2001; Kishino, 2001).