Learning Forum

[CJSmith]

Hi Folks,

Im modelling a machining process, at the moment.

The model runs after reducing the geometric strain from 1.5 to 1, all other erosion settings remain unaltered.

Following an initial period of deformation, erosion begins, and progresses linearly for the remainder of the process. The beginning of which coincides with stress reaching a steady state.

My question is, will erosion of material affect the results of other parameters. Hypothetically if the material wasn't eroded, would I get a higher measure of stress in the analysis.

Best regards,

C

[Chris Quan]

By default, Retain Inertia of Eroded Material in Erosion Controls under Analysis Settings is set to Yes. Thus, mass and momentum are still conserved even after the erosion of elements. The eroded nodes can still carry the momentum and impact any faces along its trajectory.
After an element is eroded, its volume and stress are gone. The internal energy associated to this eroded element is gone. Thus it reduces the total internal energy in the model. Usually the reduction is very small since only a very small number of elements erode.
Due to the removal of the eroded elements, the local pressure will drop. This is OK for most of impact simulations. However, if the material response is highly dependent upon local pressure, for example, concrete materials under high-velocity impact, the reduction of local pressure may affect the material behavior. In this situation, user may use SPH solver or multi-material Eulerian solver to avoid element erosion and thus model the material behavior more realistically.