All,
I am doing a PSD analysis, and when I solve the random vibration solution, a warning message shown as below:
*** WARNING ***
One or more diagonal terms of the modal covariance matrix (i.e., when mode i = mode j) is negtive; The 1 sigma results may be incorrect as...
Hi, Nettuno,
The project was canceled, so I didn't continue my analysis on the thread. However, if your load is a static one, the gap shouldn't affect the results.
Regards!
Hi, kf9ri,
Thank you for your valuable post.
It is a metal cylinder drop down. The mass is 102kg, and the height of drop will be 150mm.
I don't think Pro/Mechanica can do dynamic impact analysis(though I am not 100% sure since I don't have the module yet), so I will make some...
Hi all,
(I am re-posting the same questions as in PTC:PRO/MECHANICA forum)
I have a project like this:
A cylinder block(the mass is significant) drop on to a sheet of plastic from a certain distance, and this process will repeat 100000 times. The plastic sheet is rigid supported on all...
Hi all,
I have a project like this:
A cylinder block(the mass is significant)drop on to a sheet of plastic from a certain distance, and this process will repeat 100000 times. The plastic sheet is rigid supported on all edges. The objective is to find out if the plastic sheet is strong enough...
Thanks a lot to Peter and onlyadrafter for the suggestions!
I used helical sweep to creat the thread, which works very well. In assembly, first I align the two axis, then I use Tangent to make the teeth surface match togather(as onlyadrafter suggested), but it shows it is a invalid constraint...
Hi, all
Here I am re-posting the question I posted in Pro/MEchanica Forum.
I need to get the stress on the teeth of a pair of threads(one part is similar to a bolt, the other like a nut) , to see if the teeth will fail under an axial load. We have the theoretical value, and want to get a FEA...
Hi,
I need to get the stress on the teeth of a pair of threads(one part is similar to a bolt, the other like a nut) , to see if the teeth will fail under an axial load. We have the theoretical value, and want to get a FEA value in Pro/Mechanica. my questions are:
1) how can I make the assembly...
Hi, all,
I am running a project in Pro/Mechanica. The constraint is at 3 point. In order to get rid of the stress concentration at these points, I exclude the elements around them when I define the analysis, and ignore the stress & displacement. However, the result still shows stress...
Hi all,
I am working on a press fit problem, basically it is two circular rings fit togather. The bigger ring has a 5.0in external diameter, while the cross section is a 0.5 x 0.5 square. On the external surface of this ring, there is a circular load which is 15 lbs per inch, it should locate...