This is a past event
Modelling the fracture of brittle materials can be difficult because it involves the fast propagation of cracks.
Modelling the fracture of brittle materials can be difficult because it involves the fast propagation of cracks. Additionally the quasi-crystalline structure of rocks such as granite means that it is necessary to capture something of the microscopic structure and crack formation in order to understand the macroscopic behaviour. Analytical methods and FE analysis fall short in this respect. However, much work has been done at the University of Aberdeen to model the nonlinear response of percussive drilling modules, and a good description of the rock/impactor interaction is needed in these models.
Molecular dynamics has been used to great effect at the nm scale to predict material properties. Particle dynamics simulations work on the same basis, but the adaptation to cm scales means that if ~10^6 particles are used in a simulation they represent a number of atoms. The particles interact via a Lenard-Jones potential, and the initial configuration is achieved by using a high temperature fluid of particles and cooling at a rate appropriate for the required crystal size. Simulations reveal that cracks propagate along the crystal boundaries. Preliminary investigations into the effects of impactor shape will also be discussed.
- Speaker
- Dr. James Ing, CADR, University of Aberdeen
- Venue
- FN, G011