Authors

Abstract

The recovery of residual film in the plough layer is one of the key bottlenecks that the cotton industry in Xinjiang urgently needs to overcome. The absence of an accurate soil-residual film-cotton stubble coupled EDEM model restricts the analysis of the working mechanism and structural optimization of the soil-film separation device in full-feed residual film recovery machines.This study focuses a 20-year continuous cotton field in Korla, Xinjiang, and constructs a soil-residual film-cotton stubble coupled EDEM model. The parameters for soil models at various tillage depths were calibrated by employing a steepest ascent approach followed by a Box-Behnken experimental design, with the angle of repose serving as the response metric. The discrepancy between the simulated and experimentally measured angles of repose was less than 0.22%.The EDEM model parameters for residual film in the plough layer were calibrated based on tensile tests using tensile force and elongation as metrics. The calibration achieved errors of 0.16% in tensile force and 0.934% in elongation compared to experimental measurements. The mechanical properties of cotton stubble were analyzed using a three-point bending test, and a simulation model was constructed using the Hertz-Mindlin with Bonding V2 contact model. Incorporating the distribution patterns of residual film, a coupled EDEM model of the soil-residual film-cotton stubble mixture was developed. This model provides a theoretical foundation for designing the soil lifting and film-soil separation mechanisms of a full-feed plough layer residual film recovery machine.

Abstract in Chinese

耕层残膜回收是新疆棉花产业亟待突破的关键瓶颈之一。而土壤-残膜-棉茬耦合EDEM模型的缺乏，制约了全喂入式残膜回收机膜土分离装置的工作机理分析与结构优化。本研究以新疆库尔勒20年连作棉田为对象，构建土壤-残膜-棉茬耦合EDEM模型。采用最陡爬坡法结合Box-Behnken实验设计，以休止角为响应指标，对耕层不同深度土壤模型参数进行标定，所得模拟休止角与实测值误差小于0.22%。基于拉伸试验以拉伸力与伸长率为指标完成耕层残膜EDEM模型参数标定，拉伸力与伸长率标定误差分别为0.16%和0.934%。采用三点弯曲试验分析棉茬力学特性，通过Hertz-Mindlin with Bonding V2接触模型构建棉茬仿真模型。结合残膜分布规律构建土壤-残膜-棉茬混合物耦合EDEM模型，该模型可为全喂入式耕层残膜回收机的起土装置与膜土分离装置设计提供理论依据。