Mechanical properties of the grooved-wheel drilling particles under multivariate interaction influenced based on 3D printing and EDEM simulation

The grooved-wheel drilling device is one of the most widely used seeding and fertilizing equipment in developing countries. In the drilling process of the grooved wheel, the particles (fertilizers or seeds) are subject to great force which easily causes the particles broken or the grooved wheel stuck. Therefore, in this paper, the EDEM simulation software was used to analyze the velocity of and force on the particles in the drilling process, to obtain the maximum discharging velocity of and the force on the particles at different helix angles in the drilling process. With the 3D printing technology, a brand new grooved wheel was designed and produced. The response surface methodology was adopted to analysis of the influence of multiple factors on indicators in the grooved-wheel fertilizing process to build a multivariate regression model to obtain the best working parameters. The accuracy of the simulation and regression models was verified with fertilizer amount as an indicator. The simulation and experimental results show that in static and dynamic conditions, the force on the particles decreases first and then increases with the increase of helix angle. In static condition, discharging velocity of the particles increases first and then decrease with the increase of helix angle, followed by fluctuations in a small range. In dynamic condition, discharging velocity of the particles first decreases and then increases with the increase of helix angle, and finally fluctuates in a small range. The best parameters for fertilizing are as follows: groove radius of 13.5 mm, helix angle of 62 degrees, rotational speed of 29.4r/min, tilt angle of fertilizer feeder of 5 degrees, fertilizer amount of 17.810 g, and variation coefficient of fertilizer amount of 5.60%. The relative errors between the EDEM simulation and the regression model and the experiments are 0.90% and 3.55%, respectively. The simulation model and the regression model were built with practical engineering application value.