DEM and soil bin study of a bionic planter under yellow clay

To solve the problem of poor planting quality caused by soil adhesion on the surface of planter when working in wet yellow clay environment, inspired by the morphological structure of dung beetle head surface, a bionic convex hull planter (BCHP) was designed, and its anti-adhesion and desorption characteristics were studied to further explore the mechanism of the bionic convex hull anti-adhesion and desorption. Firstly, the dung beetle in Xishuangbanna Dai Autonomous Prefecture, Yunnan, China Province was taken as the bionic object, and the characteristic parameters of microscopic convex structure were extracted using a Bruker white light interferometer and Vision64 software, and the bionic parameter design of planter was completed. Secondly, three-dimensional models of 13 bionic planters were established by Solidworks2023, and Hertz-Mindlin with JKR model was selected as the contact model of yellow clay. Based on EDEM2019, the simulation of soil adhesion during planting was carried out. Aiming at the minimum amount of soil adhesion, the optimal values of height, diameter and area ratio of bionic convex hull were 0.67mm, 2.26mm and 43.45% respectively through Box-Behnken test and regression analysis. The anti-adhesion mechanism of the bionic convex hull was explored, and the anti-adhesion theory of the non-smooth surface was further improved based on the DEM simulation. Finally, three kinds of BCHP were processed and installed on a self-made small transplanting platform for soil tank test. The verification and comparison test results showed that the anti-adhesion and desorption effects were BCHP5, BCHP13 and BCHP4 in descending order. The test results were highly consistent with the simulation results of EDEM, which verified the reliability of the simulation model. Among them, BCHP5 had the best anti-adhesion and desorption effect, and when the moisture content was 22.72%, 27.13% and 31.94%, the average soil adhesion was reduced by 34.62%, 14.10% and 7.58% respectively compared with the prototype planter. The research results provided a feasible research method for the study of anti-adhesion and desorption mechanism of bionic convex hull and the optimal design of structural improvement of soil-engaging components.