Effects of Continuous Size Distributions on Pressures of Granular Gases

Direct Monte Carlo simulations are employed to investigate the granular pressures in granular materials with a power-law particle size distribution. Specifically, smooth circular discs of uniform material density are engaged in a two-dimensional rectangular box, colliding inelastically with each other and driven by a homogeneous heat bath at zero gravity. The resulting pressures are found to decrease as the widths of particle size distribution are increased. Moreover, the granular pressures in power-law systems are found to be unequally distributed among the various sizes of particles, with large particles possessing more pressure than their smaller counterparts. The width-dependent nature of the total pressures is induced by the more dispersion of smaller particles in the system as the particle size distribution is widened.