Research on the mechanism of adhesion and blockage of mulching device of ridging and mulching machine
摘要
Aiming at the difficult problem that the surface of the chute of the mulching device is easy to be clogged with clay when the starter mulching machine operates under the wet and sticky soil environment, the study designed a bionic convex bag chute based on the effect of bionic adhesion reduction and studied its adhesion reduction and desorption characteristics to further explore the mechanism of bionic convex bag adhesion reduction and desorption. Firstly, according to the surface characteristic parameters of the convex packet microstructure of the dung beetle head, 13 kinds of bionic convex packet soil chute were designed in Solidworks2023 software, and Hertz-Mindlin with JKR model was chosen as the contact model of wet soil particles, and then, the simplified model of the mulching device was imported into EDEM2022.2 software for the mulching simulation analysis. Finally, the soil adhesion simulation data were imported into Design-Expert13 software and analyzed by Box–Behnken experimental design and results to obtain the optimal dimensions of the surface bump structure of the biomimetic chute as follows: The bump diameter is 4.68 mm, the height of the bump is 1.5 mm, and the area of the bump is 47.86%. Field tests were carried out at the off-campus test base to verify the reliability of the simulation analysis, and it is known through orthogonal tests that the four factors of the bionic convex bag skidding trough adhesion test indexes affect the amount of adherent soil in the order from the largest to the smallest, namely, the soil moisture content, the type of skidding troughs, scraper spacing, and the operating speed. The results of the validation and comparison test show that the viscosity reduction and desorption effects of the bionic convex bag chute are I, II, and III in descending order, and the test results are highly consistent with the results obtained in the EDEM simulation, which verifies the reliability of the simulation model, among which the viscosity reduction of the bionic convex bag chute I is the best, and the average amount of soil adhesion in the soil with water content of 20%, 25%, and 30% is reduced by 36.27%, 17.08%, and 9.57%, respectively, compared to that of the prototypical chute. The results of the study can provide a feasible research method for the investigation of the viscosity reduction mechanism of the soil touching parts of the ridging mulching machine and the optimization design of the structural improvement.