Modelling Changes in the Dynamic Response of a Cantilever Beam During the Machining Process Using the Discrete Element Method

Production of high accuracy components often involves machining processes. If the machining processes are pushed to increase productivity, it can become challenging to comply with strict tolerances and surface finish requirements. Both the finite element method and the discrete element method have been used for off-line deflection compensation and stability analysis. This contribution investigates the capabilities of a simplified discrete element model in the use for offline simulation of the dynamic behavior of a workpiece during machining. A cantilever beam is modelled and the natural frequencies are monitored as material is removed. Results are compared with theoretical frequencies and with finite element analysis. The model shows a good correspondence in the frequency behavior as material is removed compared with finite element results, though the simple discrete element model under-predicts the stiffness of the beam with approximate 5% for the first two modes.