Computer simulation of liquids
Computer simulation of liquids
| Hi-index | 31.45 |
The current article reports on the further development of a new technique for the computer simulation of the quasi-static mechanics and scalar transport properties of sphere assemblages. In an extension of a previous 2D simulation to 3D, we have developed an improved computation based on several innovations: a shuffling algorithm to rapidly generate random loose-packed configurations of particles; a microcell-adjacency method to accelerate particle-contact search; a relaxation method to overcome singularities in the static transport equations; and a simulated mechanical compression to generate dense random initial states. The improved algorithm allows for 3D simulations on a workstation platform. As major results, the dilatancy (volume expansion) computed for random dense-packed assemblages is found to depend on interparticle friction, contrary to the classical Reynolds hypothesis. Also, the use of linear-elastic contacts is found to be valid near the rigid-particle limit of interest here. Experimental data from (''triaxial'' compression) tests agree well with the simulations of both the shear strength and the electrical conductivity of sphere assemblages, when proper account is taken of the actual electrical contact resistance between steel balls as a function of load. One major conclusion is that scalar transport can serve as a useful macroscopic probe of particle-contact topology in granular media.