A computer simulation of random packings and packed towers

Abstract

Several computer models of the random packing of equal spheres are developed. One model attempts to take account of the momentum effects of spheres as they are added to the packing, whilst two other models, which are based on previous work, involve only the static placement of spheres onto three others. Using the two last mentioned models, five agglomerates of 100000 spheres packed into cylinders are produced. Their voidage varies from 0.394 to 0.451, but they all have an average co-ordination number of six. The geometrical properties of the packings are analysed in detail, including the properties of the Voronoi polyhedra so formed. A further extension demonstrates a method of introducing regular crystals of any desired shape and size into the random packing. Once a model of random packing was generated, the output from it was used as input to a computer simulation of a packed tower, which takes account of the micro- mass transfer as well as the macro- mass transfer within the tower. The results show that it is easy to obtain good agreement between observation and simulation and therefore suggests that a simulation such as this may be a powerful tool for chemical engineers.