Study of connection mechanics model and mechanical properties of corn kernel carpopodium based on DEM

Abstract

To analyse the connecting force of between the corn kernel and the cob using DEM, the force-displacement curves of corn kernel carpopodium under quasi-static loading were acquired. On this basis, the connection mechanics model and the failure criterion between the corn kernel and the cob were established. In addition, the effects of type of loading, moisture content and corn variety were all considered. The test results show that type of loading and moisture content has a significant effect on the connecting force, the effects of corn variety are relatively small. The threshing force on the carpopodium in a tangential shear direction is the smallest. The threshing displacement of the carpopodium, along longitudinal and tangential shear directions, is far larger than that along the transverse compression and tension directions. The connecting stiffness of the carpopodium, along both longitudinal and tangential shear directions, is far smaller than that along the transverse compression and tension directions. The threshing force required along the longitudinal shear, transverse compression, and tension directions decreases with increasing moisture content, while it first increases, and then decreases with increasing moisture content along the tangential shear direction. As the moisture content increases, the connecting stiffness decreases, while threshing displacement increases on the whole.