关键词: 稻田, 土壤, 株间除草装置, 有限元方法, 流固耦合, 正交试验

Abstract: Aiming at the problems of low weeding rate and high seedling damage rate of existing paddy field interplant weeding device, this paper carried out finite element virtual simulation on the designed inverted Vshaped paddy field interplant weeding device. The ALE multisubstance unit algorithm was used to establish a soilwater coupling model, and a penalty function method was used to perform fluidstructure interaction between the weeding claw and the soilwater model. Using the quadratic orthogonal rotation combined experiment design method to select the machine forward speed, the rotary velocity of weeding claw and the thickness of water layer for virtual simulation experiment and analysis, the influence of each factor and its firstlevel interaction on the disturbance rate of the weeding claw and the soilwater model was obtained. The order of the influence of each factor on the soil disturbance rate was rotary velocity of weeding claw>thickness of water layer>machine forward speed. By optimizing the design of the virtual simulation test results, the optimal combination of factors and parameters of the inverted Vshaped interplant weeding device was obtained as the machine forward speed was 0.53 m/s, the rotary velocity of weeding claw was 180 r/min, and the thickness of water layer was 0.01 m. Through the verification of the simulation optimization design results, the indoor test showed that the inverted Vtype paddy field weeding device performed weeding operations with the best combination of factors and parameters. The average weeding rate was 85.04% and the average seedling damage rate was 3.62%, which met the agronomic requirements of paddy field machinery for interplant weeding.

Key words: paddy field, soil, interplant weeding device, finite element method, fluidstructure interaction, orthogonal test