Abstract:The interaction of soiltillage tool plays a pivotal role in analysis and optimization of the tillage process. The dynamic behavior of soil needs to be developed primarily when studying the soiltillage tool interaction. The simulation of soilrotary blade interaction using distinct element method (DEM) and indoor soil bin experiment were conducted to provide a better understanding of the soil movement. Firstly, DEM model of soilrotary blade interaction was established. Secondly, comparison of experimental results and simulation results were done, positions before and after tillage of surface soil particle were used as soil displacement in simulation, and tracer method was employed to measure soil displacement in experiment. Then, the movement of soil which belongs to different positions was analyzed. The results showed that soil forward and side displacement in experiment increased with increasing rotational speed of blade, the forward displacement was larger than the side displacement. The displacement of shallow soil was the largest, and then middle soil and deep soil had the minimum displacement. The closer the soil to the rotational point was, the larger the forward and side displacement of soil were. For the particles in tillage scope, the percent of particles which moved to the opposite direction were 26.2%, 72.1% and 48.4% for shallow soil, middle soil and deep soil, respectively. Most soil particles moved backward in horizontal direction during tillage process. The direction of side force and side displacement depended on the situation that the soil particle lay in the left or right side of the lengthwise edge axis. If the soil lay in the left side of the lengthwise edge axis, the side displacement was towards the left and vice versa. The soil particle moved downward with the rotary blade at the beginning of soil cutting, and later it slipped from the border of blade and being tossed up. The average error of soil displacement between simulation results and experimental results was 24.9% for soil forward displacement while 15.3% for soil side displacement. The paper studied the macro and meso movement of soil particles during rotary tillage, which is helpful to understand the interaction between rotary blade and soil and develop the mechanism of rotavator design and optimization.