SimScale CAE Forum

Relatively simple static analysis crashed


#1

A description of the project:
I have designed a baby gate to go at the top of our stairs (see photo below), and I wanted to do a simulation to ensure that it will be strong enough to support 50 pounds hanging on it while it is open (i.e. when the latch is not providing additional support).

To do this, I have a imported just the wood parts of the door (under the assumption that the aluminum balusters do not add much stiffness to the structure). For my boundary conditions, I have fixed the surfaces attached to the hinges and applied a 50 pound vertical load to the top corner of the door near the latch.

The fixed hinge surfaces:


The surfaces where the load is applied:

For more detail on how I have set up the model, please go to the link at the end of this post.

A description of what is happening:
I have successfully run this simulation once and found that the corner braces were needed for more stiffness. However, after adding those to the model, the simulation crashed, and it is not clear to me why. For some reason, the solver log is in French, so I am somewhat limited in being able to use it to debug the problem, but when I put select portions of it that look like they might be errors into Google Translate, the messages don’t sound like much of an error at all. Ultimately, this is not that complicated of a model (there’s only 8 fairly simple parts, 4 connections, and 2 boundary conditions), so there doesn’t seem to be very many places that I could have made a mistake, but clearly I must be missing something somewhere. Could someone take a look and see if they can find what I’m missing?

Link to my project:
https://www.simscale.com/workbench/?pid=221840550111099064

P.S. Unfortunately, when I reimported the model with the corner braces, I overwrote the successful simulation run, so it isn’t possible to look at that and compare the setup to see what is different.


#2

Hi again Tim! :slight_smile:

What I would assume is that the master-slave assignment should be vice versa and not as it is at the moment. If larger surfaces are chosen as Slave this can lead to wrong results and increased computational effort. I am also wondering why the log says that there are problems with the mesh as if there is some distortion in the element - maybe our FEA expert @rszoeke can comment on that to make sure this is not some sort of bug. Speaking of the mesh. I would suggest that you remove the holes in your geometry as they do not really contribute to your structural stiffness but add additional fine elements around them. @ggiraldo & @cjquijano, feel free to add your thoughts here.

Cheers,

Jousef


#3

I’ll try those suggestions and see what happens.


#4

Removing the holes and swapping the master/slave surfaces (which I believe was the real problem) in the contacts seemed to work.