peteroznewman
Subscriber

You said you wanted to know the force reaction. Set aside the question about the stress for now. I suggest you run the simulation with Linear materials. Remove the plasticity from the material model on the coarse mesh. See how much the force reaction changes when there is no plasticity on the coarse mesh. If the change is insignificant, then you can see if the model runs with a fine mesh to see how much the force reaction changes. However, it is also important to see how much the force changes when you reduce the time step size.