Modeling the impact interaction of a grain with a flat solid surface

The loading of silos with bulk grain cargo is usually done by gravity. In this case, the bulk material from the loading opening of the silo falls under the action of gravity onto its concrete bottom. The impact of the weevil is characterized by a small interval of the impact process and a significant level of impact forces. In this case, the weevils are injured, especially in the initial period of loading. A certain amount of damaged grain accumulates in the lower part of the grain mound.

In this article, on the basis of the classical theory of Hertz, theoretical studies of the shock interaction of grain with a flat solid surface of a silo are carried out. In this case, the concrete bottom is considered as an elastic half-space, and the grain of winter wheat falling on it is considered viscous-elastic. The main characteristics of the shock interaction of a weevil with a fixed obstacle are determined in the work. In particular, the values of the force of contact interaction and the maximum pressure for grains of winter wheat  were found, taking into account the initial speed of movement of the grain and the speed acquired by it when it falls to the bottom of the silo with height . Using the expansion of the integrand in the Maclaurin series, a simplified dependence was also obtained to determine the time of impact interaction of grain with the concrete bottom of the silo.

In the course of the study, the maximum pressure  was calculated, which occurs during the contact interaction of winter wheat grain with concrete. It corresponds to internal stresses  arising at the point of contact of a grain with an obstacle. The obtained pressure of contact interaction  is much higher than the average statistical ultimate strength of winter wheat, that is, the inequality  is fulfilled. This indicates the elastic-plastic nature of the deformation of winter grain, and hence its injury. The type and degree of deformation of the grain mass depends on the degree of excess .