Investigation of the Influencing Factors of Fertilizer Dropping Time for a Variable-rate Fertilizer Applicator

Abstract

HighlightsThe influencing factors of the fertilizer dropping time are determined by simulation.The relationship between the influencing factors and the fertilizer dropping time is explored on the VRF applicator.A new method is established to calculate the fertilizer dropping time.Abstract. Lag time is one of the main factors that affect the accuracy of the variable rate fertilizer (VRF) applicator. The key to correcting the impact of the lag time is to determine its influencing factors. This article focuses on the fertilizer dropping time, which is a part of the lag time, and hypothesizes that the rotational speed of the fluted roller, working length of the fluted roller, number of fertilizer particles, and the length of the fertilizer tube may affect the fertilizer dropping time. First, taking advantage of the simple and convenient setting of the working parameters and conditions of the simulation software, different working parameters were set by the EDEM software for simulation, and the simulation results were analyzed to determine that the rotational speed of the fluted roller and the length of the fertilizer tube are the main influencing factors of the fertilizer dropping time. Second, to explore the relationship between the two factors and the fertilizer dropping time in the actual work, experiments were performed on the VRF applicator. The experimental results are analyzed by ANOVA, and the analysis results show that: the correlation coefficient R2 between the rotational speed of the fluted roller and fertilizer dropping time is greater than 0.95, and there is a linear relationship between the factor and fertilizer dropping time; the fertilizer dropping time increases with increasing the length of the fertilizer tube. Finally, the rotation speed-the length of the fertilizer tube-fertilizer dropping time model was established through the multiple regression analysis. With the model, the fertilizer dropping time was accurately calculated according to the rotational speed of the fluted roller and the length of the fertilizer tube. The accuracy of the model is greater than 85%, which helps to calculate the fertilizer dropping time. This study helps to correct the lag distance by sending instructions in advance and improving the accuracy of the VRF applicator. Keywords: Fertilizer dropping time, Fertilizer tube, Rotation speed, VRF.