Su Qiang, Ma Xuejie, Liu Wenhang, Zhang Jianchao, Yu Zhihong, Liu Zhixing
College of Mechanical and Electrical Engineering, Inner Mongolia Agricultural University, Hohhot, China.
Front Plant Sci. 2025 Apr 29;16:1590054. doi: 10.3389/fpls.2025.1590054. eCollection 2025.
The interaction between Kom. (CKB) branches and crushing machinery is complex, requiring a detailed mechanical model to effectively describe the fracture characteristics of CKB during crushing. This study aims to develop such a model using the discrete element method to simulate the elastoplastic fracture behavior of CKB.
A mechanical model for CKB was established based on its fracture mechanical characteristics. The model incorporates elastoplastic stages, including elastic, elastoplastic, and fully plastic phases during stem crushing. A parameter calibration method was employed, combining physical experiments with simulation experiments to refine the discrete element model. The key binding parameters of the model were optimized to best simulate the mechanical properties of CKB under various loading conditions.
The optimal binding parameters for the flexible discrete element model were identified as: normal stiffness of 3.67×10 N·m, shear stiffness of 3.42×10 N·m, critical normal stress of 6.57×10 Pa, and a binding radius of 0.78 mm. The model successfully replicated the elastic stage force-displacement curve in compression tests with an error of only 0.24%. The discrepancies between simulated and actual fracture forces were 2.79% for compression, 4.68% for bending, 4.14% for shear, and 8.64% for tensile tests, showing good agreement with experimental results.
The developed model accurately simulates the elastoplastic fracture behavior of CKB under compression, bending, and shear, providing valuable insights into the crushing mechanism of CKB. The calibration process demonstrated that the proposed DEM model can be an effective tool for exploring and optimizing the crushing process of CKB.
Kom.（CKB）分支与破碎机械之间的相互作用十分复杂，需要一个详细的力学模型来有效描述CKB在破碎过程中的断裂特性。本研究旨在使用离散元方法开发这样一个模型，以模拟CKB的弹塑性断裂行为。
基于CKB的断裂力学特性建立了一个力学模型。该模型包含弹塑性阶段，包括茎干破碎过程中的弹性、弹塑性和完全塑性阶段。采用了一种参数校准方法，将物理实验与模拟实验相结合来优化离散元模型。对模型的关键粘结参数进行了优化，以最佳模拟CKB在各种加载条件下的力学性能。
确定了柔性离散元模型的最佳粘结参数为：法向刚度3.67×10 N·m、剪切刚度3.42×10 N·m、临界法向应力6.57×10 Pa和粘结半径0.78 mm。该模型在压缩试验中成功复制了弹性阶段的力-位移曲线，误差仅为0.24%。模拟与实际断裂力之间的差异在压缩试验中为2.79%，弯曲试验中为4.68%，剪切试验中为4.14%，拉伸试验中为8.64%，与实验结果吻合良好。
所开发的模型准确模拟了CKB在压缩、弯曲和剪切下的弹塑性断裂行为，为CKB的破碎机制提供了有价值的见解。校准过程表明，所提出的离散元模型可以成为探索和优化CKB破碎过程的有效工具。
