Discrete element simulations of the influence of fertiliser physical properties on the spread pattern from spinning disc spreaders

This paper describes a sensitivity study of the flow of granular fertiliser particles on a spinning disc using a discrete element model. The aim was to get a qualitative insight in the influences of individual physical properties of the particles (such as friction coefficient, restitution, and shape) as well as their bulk behaviour on the resulting spread pattern. The results show that certain particle properties, particularly friction coefficients, have a large influence on the spread pattern, and hence should examined carefully in the process of producing granular fertilisers, perhaps by particle coating, or taken into account when applying the fertiliser in the field. Other properties, such as particle stiffness hardly affect the results. Furthermore, it was shown that the friction coefficient and shape of a particle strongly interfere in their particular influence on the spread pattern. Overall, the discrete element model could provide a powerful instrument for the manufacturers in the development of new kinds of spreaders and fertilisers.