Simulation of Plastic Deformation Failure of Tillage Tools Based on the Smoothed Particle Hydrodynamics Method

The problems of large deformations, failures, and fractures that agricultural tillage tools may encounter during the cultivation process has long been a concern in the field of agricultural machinery design and manufacturing. It is important to establish a more accurate numerical model to effectively predict tools' plastic deformation failures and ductile fracture failures. This research develops a numerical model for predicting the plastic deformation failure and ductile fracture failure of agricultural tillage tools using the smoothed particle hydrodynamics (SPH) method and the Johnson-Cook constitutive model. The model uses the Drucker-Prager criterion to describe the elastic-plastic constitutive behavior of the soil, the von Mises criterion to describe the Johnson-Cook constitutive model of the tool, and the coupling condition with the Lennard-Jones repulsive force to describe the interaction between the tool and soil. The numerical results show that the proposed model can effectively simulate the interaction between the tool and soil, as well as the tool's plastic deformation failure and ductile fracture failure during the agricultural cultivation process. It can also predict the variation trend of the cutting force of the tool. This helps to provide a new approach for the numerical simulation of such problems.