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Hi there,

I'm currently at university and trying to figure out Explicit Dynamics for the first time, my simulation involves a bumper system (bumper beam, 2 crash boxes and a beam which I have changed the density of to simulate the weight of the car). I have given the impactor an initial velocity and it impacts the beam correctly and has an appropriate bounce back, there is plastic deformation. I was wondering if there is any to calculate the actual deformation of the beam without including the velocity (as far as im aware, the deformation solution also takes into account movement from the initial position). The method i'm currently using is exporting the results for the deformation of the beam to excel, then choosing a reference point slightly behind the beam in terms of an element where deformation is at a minimum, in order to calculate the deformation without the movement component, is there any way such as a user defined result or an easier method which I could use to achieve the deformation I want to record without it taking into account the movement from it's initial position?

Thanks

[peteroznewman]

ArraynTaking the difference in displacement between two nodes, one on the car beam and one on the bumper beam is a good way to get relative deformation of the bumper.n

[Scooped]

nThank you so much for the quick reply! I can't express how much many of your answers on previous threads have sorted my problems, keep up the good work! One more thing if you don't mind me asking, is it normal for there to be stresses still inside a part of the model which has undergone plastic deformation? As only half of the peak stress dissipates in the time I have modelled (0.1 second), I can however seen the stresses slowly leaving the beam towards the end of the simulation, thanks for the original reply and no worries if you can't answer this one!n