Simulation of Soil Deformation around a Tillage Tool using Computational Fluid Dynamics

Tillage tool modeling concerns primarily soil deformation patterns and force requirement as the tool interacts with soil. Though there is much literature available on soil forces and energy consumption with respect to the soil mechanical behavior considering soil as a solid or elasto-plastic material, large soil deformations resulting from the tool action have not been studied. This paper deals with preliminary modeling of soil flow around a tool using the computational fluid dynamics (CFD) approach. Main objective of this modeling was to characterize soil as a Bingham fluid to determine soil flow pattern around the tool. Simulations were based on the governing equations of non-Newtonian fluid flow with the viscoplastic constitutive relationship. Simulations were carried out using commercial software CFX 4.4. Initial results look promising in identifying soil deformation patterns, quantifying soil failure front and analyzing effect of speed on the failure front propagation. Further studies with this fluid flow approach are expected to reveal details of soil behavior around a tillage tool.