Modeling the effect of different oscillation angles on the oscillatory tine performance using Discrete Element Method

Document Type : Research Paper



Interaction between soil and machine is essential challenge for researchers, developers, designers and manufacturers of agricultural machineries. Modeling of tillage equipment is an important Engineering work. However, interaction modeling is a complex process due to three-dimensional changes in soil, nonlinear soil behavior phenomenon and soil flow quality in connection area between the soil and tool and the dynamic effects of equipment. Correct simulation of the interaction of soil is the key point for the optimization of tillage tools and can eliminate required field tests with high costs. The purpose of this study is to develop a three-dimensional model of a vibrating subsoiler using discrete element method, simulation frequency and oscillation angle on the performance of vibration subsoiler and determining different parameters affecting the simulation results. The information from model simulation will be useful for the design and optimization of vibrating subsoiler. For modeling soil mass as a granular material, the computer program PFC3D. Blade was moved with angular and transition speed in the positive x-axis direction. For non-vibrating blade only included transition speed and for vibration blade in addition to transition speed, angular velocity was also defined. Working depth was 38 cm and blade speed of 0.89 meters per second was defined. To evaluate the effect of vibration angle on vibrating subsoiler different vibration of 27, 16, 8, zero,-14.5,-22.5 degrees in frequency of 4.9 Hz and amplitude of ± 69 amplitude was tested by simulation. In all vibration tests in comparison with non-vibrating,with Increasing vibration angle (positive and negative), the amount of vertical displacement of blade increased which caused more soil rupture. Simulation results showed that the rate of boundary work, kinetic energy and friction work at positive angles were more than negative vibration angles. With increasing negative angle boundary work and friction work significantly decreased. Changing the angle from -22.5 to 27 degrees decreased average bond energy of particles.


Main Subjects

Asaf, Z., Rubinstein, D., Shmulevich, I. (2006). Evaluation of link-track performances using DEM. Journal of Terramechanics. 43, 141-161.
Asaf, Z., Rubinstein, D., Shmulevich, I. 2007. Determination of discrete element model parameters required for soil tillage. Soil and Tillage Research. 92, 227-242.
Coetzee, C. J., Els, D. N. J. (2009). Calibration of granular material parameters for DEM modelling and numerical verification by blade-granular material interaction. Journal of Terramechanics. 46(1), 15-26.
Franco, Y., Rubinestein, D., Shmulevich, I. (2006). Prediction of soil–bulldozer blade interaction using Discrete Element Method. Trans. ASABE. 50(2): 345-353.
Eggenmuller, A. (1958). Oscillation tools for soil cultivation:Kinematics and testing of single model tools. Grundlagen der. Landtechnik. 10, 55-70.
Itasca manual, (2006b). PFC3D User’s Manual, Version 3.1., Itasca Consulting Group Inc., Minneapolis, Minn, USA.
Sakai,K., Hata,S.I., Takai, M., Nambu, S. (1993). Design parameters of four-shank vibrating subsoiler. Trans. ASAE. 36(1):23-26.
Shahgoli, G., Saunders, C., Desbiolles, J., Fielke, J. 2009. The effect of oscillation angle on the performance of oscillatory tillage. Soil and Tillage Research, 104(1), 97-105.
Upadhyaya SK, Rosa UA, Wulfsohn D, 2002. Application of the finite element method in agricultural soil mechanics. Adv Soil Dynamics, 2, 117-153.
Shmulevich, I, (2010). State of the art modeling of soil–tillage interaction using discrete element method. Soil and Tillage Research. 111, 41-53.
Van der linde, J. (2007). Discrete element modelling of vibratory subsoiler. Master thesis, University of Stellenbosch, South Africa.