基于SPH-FEM耦合方法的圆锯片切割石材数值仿真研究

Numerical simulation of stone cutting with circle saw based oncoupling method of SPH-FEM

针对圆锯片切割石材过程中复杂的动态力学行为,依据脆性材料断裂理论,基于有限元与光滑粒子耦合算法(SPH-FEM)模拟了锯片-石材切割系统的复杂动力学加工过程。模拟结果表明:在切割过程中石材去除过程分为塑性变形阶段、小规模挤裂阶段、大规模挤裂阶段和重复大规模挤裂阶段;切割过程中切割力从零开始,接触石材先瞬间增大,然后又减小,最后在一定范围内平稳波动;根据锯片结构表面等效应力分布情况确定了模型最易破坏的区域。通过试验对比验证了该耦合算法的可行性,表明SPH-FEM耦合算法能准确获取切割石材时系统的动力学响应信息,为揭示锯路拓展及石材动态损伤、成屑机理提供理论支撑。

Aiming at the complex dynamics behavior of stone-cutting with circle saw blade, according to brittle material fracture mechanism, the complex dynamics working process of the saw blade-stone cutting system was simulated based on the coupling SPH-FEM coupling method.The results showed that the stone cutting process was dividedinto four stages,including plastic deformation,small-scalecracked stage,large-scale cracked stage and repetitivecracked stage. The cutting force was zero atthe beginning of the process, and increasedrapidly when the blade contactedwith the stone,then decreased, and fluctuated smoothlyeventually. The easily damaged region was determined according tothe equivalent stress distribution of saw blade. At last, the feasibility of the coupling algorithmverified according to the comparison of the experiment. It was shown that the SPH- FEM coupling method couldobtain the dynamics response information of the cutting systemaecurately. Thisprovided a theoretical referencefor the saw route expansion, stone dynamical damage and chip formation mechanism.