Division of Information Technology, Engineering and the Environment
School of Advanced Manufacturing and Mechanical Engineering
School of Advanced Manufacturing and Mechanical Engineering
Thesis Abstract
Tillage operations for agricultural operations are a vital part of crop production for both weed control and creation of a seed bed. Economical and environmental considerations are forcing farmers to manage soil tillage with an optimum implement configuration to get a desirable soil condition. Energy used for tillage processes has a significant proportion in total energy usage in crop production. Understanding tillage tool design parameters will help with tillage tool design and selection. Although some experimental and numerical studies, which are based on finite element modeling, can be found in the literature to simulate soil-tool interactions, none of them give accurate results when the dynamic effects are considered. In addition none of them can predict the changes in soil structure with high accuracy. Modeling of soil-implement interaction is a complex process due to variability of the soil profile, non-linear behavior of the soil material, and dynamic effect of the soil flow and an approach which should be able to give further insight is through the technique of discrete element modeling (DEM).
DEM is now an effective simulation modeling tool for bulk handling of minerals and agricultural products and has to the potential to accurately simulate tillage. It examines the dynamics of discrete particles in a granular media and solves engineering problems that are modeled as a large system of discrete interacting general shaped bodies or particles subjected to gross motion. Although there are few articles related to discrete element modeling of soil-tool interaction, none of them considered the cohesion and can be just used for rough estimation of the model parameters. The software EDEM will be used to model the action of shallow working sweep wing tillage tools that have been previously studied at UniSA with regards to tillage forces and furrow profile. The approach will be to firstly examine soils that do not adhere to the tool and to then include adhesion to the model. Results will be compared to past field tests and FEM results.
