Simulation of bulk density distribution of wheat in silos by finite element analysis

Bulk density is a critical parameter for predicting grain pressures in silos, determining the resistance to airflow, and estimating the grain mass in storage bins, so studying the bulk density distribution is critical for the storage security of wheat during storage. To investigate the bulk density distribution of the wheat bulk stored in an axisymmetric steel silo with flat bottom, the Modified Cam-Clay model was applied to calculate the bulk density of wheat at four different moisture levels at different depth and radius of the silo. The results showed that the bulk density of wheat at different depth was not uniform and it increased with increasing grain depth but decreased near the wall-bottom of silos. Moreover, it was found that the bulk density of the wheat decreased with increasing radius at the same depth and the same moisture content. Furthermore, the mean bulk density of a layer of wheat was negatively correlated with moisture content at the same grain depth and approached a plateau value when the wheat was close to the bottom of the silo at the same moisture content. The bulk density was adequately fitted as a function of the grain depth and moisture content in silos.