关键词: 生物炭还田, 洛基程序, 离散元仿真, 响应面试验, 参数优化

Abstract:  At present, the process of biochar return to the field is complicated, laborious and time‑consuming. In order to achieve the integration of trenching, biochar distribution, and soil covering for biochar return to the field, the key components for the biochar distribution system on the biochar return machine are designed, such as a trenching shovel and a biochar distributor. A simulation model of the key components is established by using the discrete element software Rocky to simulate the process of biochar return to field. The variability coefficient of biochar distribution  is taken as the experimental index, the exit distance, the diameter of the conduit and the angle of the deflector blade as experimental factors, the Design-Expert software is utilized to design a single‑factor experiment and a three‑factor, three‑level response surface experiment, the optimal working parameter combination is obtained through the analysis of response surface plots and parameter optimization modules, the outlet distance is 65.20 mm, the conduit diameter is 25.30 mm, and the baffle angle is 30°. The experimental results indicate that the variability coefficient of biochar distribution of the key components designed in this paper is 28.622% under the optimal working parameters, and the trenching, biochar distribution and soil covering process can be completed in one pass,  which can provide a reference for the technology of biochar return to field.

Key words:  biochar return to field, Rocky program, discrete element simulation, response surface test, parameters optimization