3D numerical modelling of solid particles with randomness in shape considering convexity and concavity

Comparison of Geometric Properties of Regular and Irregular Mineral Grains by Dynamic Image Analysis (2D) and Optoelectronic Analysis (3D) Methods

The properties of bulk materials are influenced by geometrical features of grains such as size, size distribution and shape. However, size is an ambiguous parameter for non-spherical particles. Therefore, the influence of the shape of a particle on its size, as described by various measuring methods and estimators using the main particle dimensions, was studied here. Granulometric analyses of mineral raw material samples containing regular and irregular grains were performed as part of the research. The measurements were made using two methods: the dynamic image analysis and the optoelectronic analysis. The main dimensions of the particles in 2D and 3D space were measured. Particle shape descriptors were determined based on the measurements: circularity and sphericity. Particle size distributions were also determined as a function of the minimum and maximum Feret diameters (for the 2D method) and the shortest and longest dimensions of particles recorded by the 3D method. The distribution of grain shapes according to Zingg classification was used for the 3D method. The results of the study were discussed in the context of comparing both of the measuring methods and selecting the most appropriate one to assess particle (ir)regularity.