Abstract

In several applications of scientific and industrial relevance involving multi-fracturing solids and/or particulate media, the system response is governed by the presence of an additional phase, either gaseous, liquid or both; or by the need to consider other physical phenomena, such as thermal effects. Alternatively, the problem may involve the combined flow of particles interspersed with fine grained material, necessitating a multi-scale approach to solution. The presentation considers the essential issues necessary for an effective computational treatment of such coupled systems, with the most appropriate route to solution being highly problem dependent. After discussion of issues related to the constitutive and computational modelling of continuum to discrete transformation phenomena, specific problems that are addressed include: (a) impact and explosive loading applications where, coupling takes place through an interdependence between the evolving gas pressure distribution driving the fracturing process which, in turn, provides the porosity distribution which controls the gas pressure, (b) particle transport problems in which the particles being transported through the fluid are large and extend over several fluid grid cells and© fines migration problems in which fine particles that are several orders of magnitude smaller than the main rock fragments flow through the moving particle system. A further problem addressed is heat transfer between a moving particle system at elevated temperatures and a surrounding pressure driven gas environment.

Applicability of the methodology developed is illustrated through practical examples related to defence applications, rock blasting events, pebble bed reactor technology and mineral mining/processing operations