I'm trying to simulate the behavior of a plastic component in Nastran NX 10. This component has some clips, and I need to enforce a displacement of 1 mm in X and Y direction on the top edge of the clip, in order to simulate its working position.
I was able to run the simulation (using SOL106 - Global Constraints), and the stress of the clip results as expected.
However, I need to know the force needed (in X and Y) to compress the clip.
I looked everywhere in the post processing, but I can't find the values of the load.
Am I missing something? Attached you can see a picture of how I set the enforced displacement. The only other constraint is a fixed support on the bottom of my plastic component.
Thanks in advance,
thanks for the quick reply. I already tried it (see attached picture): I get a force (on axis Y it's -2.5 N), but if I remove the enforced displacement constraint, and apply a force of -2.5 N, the re-run the simulation, I dont get 1 mm of displacement (I get 0.644).
So I assumed that reaction force output wasn't what I was looking for.
Again, am I missing something?
Thanks a lot,
This is nonlinear problem. Maybe this clip have snap-through behavior. Save intermediate results and plot diagram Reaction vs. Time. Maybe you have peak somewhere in the middle of diagam. Try to use peak value instead of end value.
I run the simulation using 10 subcases. I tried to plot the reaction force on Y over the iterations (see attached picture), but as expected, the peak is at the last iteration. Plus, I need to know the force on the edge when the clip is in its working position (X and Y displacement = 1 mm), not in a different one.
After many attempts applying a simple load on the edge, I found that I need a Force of Fy=-4,5 N along (axis Y) and Fx=2.25 N (along axis X), in order to get the correct displacement of -1 mm along Y and 1 mm along X.
But then again, if I set the required enforced displacement, and in the last subcase I use the identify command on the whole edge, the sum of the reaction forces on the nodes is Fx=0.6 N and Fy=-2,5 N. these values are not correct.