Transmission of force through particulate systems with restricted geometry

Particle systems may be characterised by a knowledge of the dimensions of the individual particles. By using the Feret's diameter distribution and the random filament distribution of an iron powder the characterisation of a system of the powder particles, constrained in a cylindrical die, has been achieved. The Monte Carlo method has been used to simulate the transmission of force through the model created by this characterisation. The results of 500 Monte Carlo simulations have been used to produce a description of the force due to one surface particle at various points in the system. Using this diagram together with a knowledge of the spatial distribution of the surface particles and the dimensions of the die it was possible to produce: (1) curves of side wall pressure vs. depth in the die for various loads; (2) curves of applied to transmitted pressure for various height:diameter ratios; (3) curves of friction loss at the walls vs. depth for different height:diameter ratios. The differences between the experimentally determined values and the values predicted on the basis of the model have been explained in terms of the assumptions made, and suggestions made as to how these may be eliminated.