Dynamic Analysis of Soil Tillage Using Computational Fluid Dynamics

Soil cutting for preparing a proper seedbed with the purpose of crop production is tillage. Though tillage is a dynamic process, most of the previous studies are based on quasi-static analysis following the passive earth pressure theories. The focus of this research was to describe the mechanical behavior of soil under the action of a tillage tool from the dynamic perspective using fluid flow analysis. This paper describes the application of a commercially available, three-dimensional computational fluid dynamics (CFD) model to simulate and analyze dynamic tool interaction with soil during tillage.

Soil has been considered as a Bingham material taking into account its non-Newtonian viscoplastic behavior. Simulations used a rectangular flow geometry based on the tool influence zone obtained from previous research. Soil flow behavior has been studied as a conduit with the interaction of a bluff body in the flow domain. With a more realistic approach, free-surface simulations were carried out to observe the soil deformation pattern due to tool interaction during tillage. Soil pressure on the tool surface was also investigated.