Discrete element method simulation of corn root residue excavation for structural design and performance optimization

To address the issues of high resistance and low efficiency in corn root residue excavation in cold, arid regions, a serrated double-wing blade was designed based on root distribution and mechanical properties. A mechanical model of blade–soil–root interaction was established, and EDEM simulations were conducted to optimize serration geometry and blade parameters. Optimal serration dimensions were determined as 5 mm height and 8.77 mm spacing. Through an orthogonal experiment, the best structural parameters were found to be a 23.4° entry angle, 59.2° wing angle, and 244.06 mm blade width. A prototype was fabricated, and field tests were performed to evaluate forward resistance and root-lifting rate under different operational settings. The optimal working conditions were a 15.5° soil entry clearance angle, 130 mm excavation depth, and 5 km/h forward speed. Under these conditions, the average forward resistance was 2025.81 N, and the root-lifting rate reached 85.6%, meeting operational requirements and verifying simulation accuracy. The results provide theoretical and practical references for the design of efficient excavation tools for compost-based corn residue return in similar environments.