GUI Contact tutorial: different History Outputs

General Questions
1

Hi,
I developed the model exactly as per the tutorial but the reactions turn out very different. This the history
Time [s]
Frequency [Hz] RF1
[N]
0.1 61.78041
0.2 231.0571
0.3 368.9133
0.4 296.1608
0.5 292.9952
0.6 217.9696
0.7 133.1361
0.8 25.80724
0.9 -28.81433
1 -35.33603
Apparently the model works as in the tutorial.

2

Please share the .pmx file. You can use some hosting website like Google Drive, Dropbox or WeTransfer and paste the link here.

3

Thanks
https://www.dropbox.com/scl/fi/k9znmiddgb3vltxspdocg/Contact.pmx?rlkey=3m7b52ey51iqcpk0c1s9qzjx2&dl=0

4

In which version of PrePoMax was this file created ?

5

I had run with version 1.5.0. but I get the same result with update 1.5.3:
Time [s]
Frequency [Hz] RF1
[N]
0.1 61.78041
0.2 231.0571
0.3 368.9133
…

6

Compare the number of nodes on that back face in the tutorial and in your model. I think that the results are not the same because of this difference combined with the fact that there are both positive and negative reaction force values in that node set and the summation performed when the Totals option is enabled doesn’t use absolute values.

7

Okay I will investigate in this direction. Thank you for the time you’ve dedicated to this case.

1 Like
8

Yeah, basically compare the results for different mesh sizes because that’s the only difference here. You can apply that fixed BC via a rigid body constraint and read the RF from it to get the actual total reaction force, independent of the summation.