Construction of Discrete Element Model of Different Moisture Hygroscopic Fertilizer Particles and Fertilizer Discharging Verification

The hygroscopic fertilizer particles were characterized based on discrete element simulation, and its accuracy was verified by the simulation of fertilizer discharge. Firstly, the repose angle of the fertilizer particles served as the key metric for assessment. A mathematical model characterizing the relationship between fertilizer moisture content and the repose angle was established, R2=0.9935; and a mathematical representation of the repose angle for fertilizer moisture content was established, R2=0.9933. Then, the moisture absorbing fertilizer particles was developed utilizing the integrated Hertz Mindlin with JKR model within EDEM system to account for particle adhesion; A robust correlation model between the repose angle of hygroscopic fertilizers and the discrete element method was established, p <0.0001; Finally, a correlation model between moisture content and significant parameters within the discrete element method was established, drawing upon the models for moisture content repose angle and repose angle discrete element parameters. The moisture-absorbing fertilizer particles model at moisture contents of 2% and 6% were resolved, with a relative error of the repose angle not exceeding 1.42% and a single circle fertilizer discharge error below 8.32%. The results show that the moisture content discrete element significant parameter correlation model can reliably and precisely forecast the discrete element parameters of various moisture content hygroscopic fertilizers. The hygroscopic fertilizer particle model can represent surface interaction characteristics of hygroscopic fertilizer granules. which has guiding significance for the design of precision fertilizer discharge technology device.