基于AgriDEM软件的小麦根系建模与试验验证  

Modeling and verifying wheat roots using AgriDEM

作　　者：赵瑾汶 于建群[1] 孙凯 孙永昌 王扬[1] 梁留锁[1] 于亚军[1] ZHAO Jinwen;YU Jianqun;SUN Kai;SUN Yongchang;WANG Yang;LIANG Liusuo;YU Yajun(School of Biological and Agricultural Engineering,Jilin University,Changchun 130022,China)

机构地区：[1]吉林大学生物与农业工程学院,长春130022

出　　处：《农业工程学报》2025年第3期63-72,共10页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金重点项目(52130001)。

摘　　要：为设计和优化小麦收获后的旋耕灭茬机械关键工作部件,应用离散元法对小麦根系进行建模和分析,需对其接触力学参数进行标定。该研究以成熟期小麦为对象,建立小麦根系模型并进行试验验证。首先,在小麦根系物理力学性质测试分析的基础上,采用自主研发的软件AgriDEM,建立了小麦单条根和整株根系的离散元模型。然后,通过单条根的拉伸试验和仿真,确定了不同含水率(6%、15%和27%)下单条根的极限应力和弹性模量,并对平行粘接模型的各项粘接参数进行标定和优化。通过土壤堆积角试验和仿真,确定了土壤仿真使用的“黏颗粒”接触力学模型各项参数。最后,进行了单条根埋入土壤中的拉拔试验以及实际根系在土壤中的拉拔试验和仿真。结果表明,仿真和试验中单条根和实际根系受到的平均最大拉拔力相对误差均在15%以内,由此证明了所建立的单条根和整株根系模型及参数的准确性。研究结果可为小麦收获后耕整地过程的仿真分析奠定基础。Stubble crushing machine has been widely used in the rotary tillage after wheat harvest.The wheat roots can often be simulated using the discrete element method.It is very necessary to calibrate the mechanical parameters for the better contact performance during crushing.In this study,a series simulations and tests were implemented to verify the wheat root system.The root system of Ningchun 4 wheat plant at mature stage was taken as the research object.The tensile and shear test of single root were carried out.The ultimate stress and elastic modulus of single root were calculated with the different water content(6%,15% and 27%).The geometric morphology of the roots was characterized in the soil,together with the lateral roots at all levels.Each root was simplified to be straight and evenly distributed.The discrete element model was established for the single and whole root of wheat using the self-developed software,AgriDEM,according to the database of non-spherical particle filling ball modeling function.A flexible root model was established to bend at any position.The 'parallel bonding model' was used as the mechanical model of the connection between adjacent particles inside the roots.The Plackett-Burman and Box-Behnken simulation test were carried out,according to the tensile test and simulation of a single root.The bonding parameters of the 'parallel bonding model' were calibrated and then optimized.Because the soil type was the viscous and compressible loam in the wheat planting area,the 'clay particle model' was used to characterize the soil characteristics.According to the soil accumulation angle test and simulation,the parameters sensitive to the soil accumulation angle were selected by parameter sensitivity analysis.The linear fitting was used to obtain the static friction coefficient,sliding friction coefficient and adhesion coefficient,and the linear relationship between the above parameters,as well as the soil accumulation angle.There was the linear relationship among them.Finally,some parameters were

关 键 词：离散元法 AgriDEM软件 小麦根系 根土复合体 拉拔试验 

分 类 号：S126[农业科学—农业基础科学]