Discrete element method (DEM) simulation to improve performance of a mouldboard skimmer

Abstract

Historically, most mouldboard plough research has been focused on improving the performance of the mouldboard itself, with very little focus on other plough components such as the skimmer. The skimmer is a critical additional component of the overall mouldboard plough which affects its performance in the field. The skimmer has a significant effect on the ability of the plough to bury topsoil and surface residues and there is a need to understand the effect of speed, depth and critical working angles on both forces and soil movement. Soil bin and analytical studies by Saunders (2002) investigated the potential to improve soil-skimmer interaction. Recent studies have shown that discrete element method (DEM) has the potential to predict both tillage forces and soil movement of tillage implements. In this study experimental and analytical work carried out by Saunders (2002) was replicated using a DEM simulation. A good correlation was obtained between the measured and predicted draught (R2 = 0.9) forces, furrow area (R2 = 0.68) and maximum soil throw (R2 = 0.77) while a fair correlation was obtained between measured and predicted and vertical forces (R2 = 0.5). It was also found that better draught force prediction can be obtained using DEM than with an analytical method. Results of the study showed that DEM has potential to accurately model tillage forces and soil movement and guide improvements to skimmer working angles.