Simulation and Experiment of Fertilizer Discharge Characteristics of Spiral Grooved Wheel with Different Working Parameters

Fertilizer particles have strong hygroscopicity and agglomeration often occurs during their storage, which leads to a blocked phenomenon during the operation of the external grooved wheel fertilizer discharger. In this study, the bond model of fertilizer block was constructed based on the discrete element method (DEM) to further explore the effect of different working parameters of the spiral grooved wheel on the fertilizer discharge characteristics. According to the Box–Behnken experimental design principle, a three-factor and three-level simulation experiment was carried out with the factors of grooved wheel speed, grooved wheel section shape, and spiral rise angle. The simulation results showed the variation coefficient of fertilizer uniformity was affected, from important to secondary, mainly by the rotating speed of the grooved wheel, the cross-sectional shape of the grooved wheel, and the spiral rise angle. The broken rate of fertilizer block bond was affected, from important to secondary, mainly by the spiral rise angle, the cross-sectional shape of the grooved wheel, and the rotational speed of the grooved wheel. The optimal combination of working parameters was obtained by optimizing and analyzing the data; the rotating speed of the grooved wheel was 21 r/min, the scoop section, and the spiral rise angle was 70°. Under the best working parameters, the variation coefficient of fertilizer uniformity was 8.56%, and the broken rate of fertilizer block bond was 97.67%. The validation experiment results showed that the variation coefficient of fertilizer uniformity was 9.23%, the broken rate of fertilizer block bond was 94.28%, and the relative data error was less than 10%. The experimental results are close to the simulation results. The research results can provide a reference for the structural design and parameter optimization of spiral grooved wheel fertilizer discharger.