If one concerns the behavior of fine particles in questions of conveying and handling, the contact mechanics between the particles themselves and the particles and their surroundings are crucial. If one wants to predict the behavior of a particle-collective one first step is the examination of a single particle-particle or particle-wall contact. Aim of the project is to simulate the contact of a particle with a wall in gaseous environment. Two different contact cases are examined, a smooth particle with one and a rough particle with two contact points on a wall. For these cases distribution functions, especially for the adhesion-moment, have been developed to predict the strength of the contact against external stress. A C++ based simulation has been written, which calculates the van der Waals interactions for the two contact cases. In both cases a particle flattening is taken into concern. The simulation works at an atomic scale, which means that the particles are entirely constructed of single atoms. Because of this building method a large variety of shapes or surfaces could be designed. The adhesion force of the particle is calculated following the principle of superposition. The simulation is built modularly, so that it can be easily extended or adjusted. The simulation is able to scan a three-dimensional space in steps of one atomic diameter. According to geometric conditions the simulation decides whether the examined point - which has the same coordinates as the possibly existing atom -is part of the particle or not. If the point is part of the particle geometry an atom is set and the adhesion force is calculated. The particle can be built in a cubicprimitive, cubic-face centered or cubic-body centered lattice. To face the problem, that the simulation always builds perfect atomic lattices, material porosity was implemented. Real material has always errors and flaws within its atomic lattice. This decreases the atomic density of the particle and in consequence the total number of atoms within the particle volume. The porosity eliminates atoms by chance following a user given value for the porosity of the particle material. Different types and numbers of roughnesses are possible to simulate the surface structure of a particle. The results of the adhesion force and moment values of rough and smooth particles will be shown. (C) 2015 The Authors. Published by Elsevier Ltd.
