Discrete Element Modeling and Verification of an Outer Groove Wheel Fertilizer Applicator with Helical Teeth

Abstract

Highlights An outer groove wheel fertilizer applicator with helical teeth was designed. The helical teeth made the fertilizer mass and kinetic energy more stable. The fertilizer mass rate was sensitive to the working length and rotational speed. Abstract. The fertilizer applicator plays an important role in making fertilization efficient, and a fertilizer applicator called the outer groove wheel fertilizer applicator (OGWFA) is widely used in the middle of China. An OGWFA with traditional straight teeth has a pulsation phenomenon and problems with breaks in application. To improve the fertilization performance, an OGWFA was designed with helical teeth in a staggered arrangement. The helical angle is an important parameter for the outer groove wheel (OGW), and 47.5° was considered a reasonable helical angle for this OGWFA according to fertilization performance simulated using discrete element modeling (DEM). The performances of OGWFAs with 47.5° helical teeth and with straight teeth were experimentally compared and analyzed by DEM. The OGWFA with helical teeth obtained lower coefficients of variation (CV) and break rates and smaller width of the fertilizer distribution. The simulation showed that the helical teeth made the fertilizer discharge more stable. The effects of working length, rotational speed, and coefficient of static friction between fertilizer particles on OGWFA performance were also simulated. Keywords: DEM, Discrete element method, Fertilizer applicator, Outer groove wheel.