Foreword on the special issue: from discrete particles to continuum models of granular mechanics

Abstract

The mechanics of granular materials have remained a challenge to describe since the days of Coulomb, both theoretically and computationally. Granular media arise in a number of everyday circumstances (e.g., raw materials, soils, food/agriculture, pharmaceuticals, vehicle mobility, debris removal) and remain the second-most handled material by weight in global industry. Hence, the challenge of coming up with accurate and efficient ways to simulate a collection of grains is an issue of great import to multiple disciplines. There are two major perspectives. Ideally, one would like a continuum model able to describe the behavior of large collections of grains in a numerically efficient fashion. There is also the discrete perspective, where modeling arises at the individual particle level and the motion of every grain is tracked and evolved under mechanical laws.