nat. frequency analysis in pro/e

[dalej2]

i want to determine the natural freq. of a panel that has a 2 hp motor attached to it running at 1160 rpm.

should i create an assembly with the panel and motor and go into the mechanism module and add a motor to simulate the 1160 rpm...? will mechanism be able to tell me the nat. freq. or do have to import that data into mechanica and set up a design study creating a new modal, and new dynamic freq. analysis, then run, the program...?

 

[JohnAndrews]

Natural frequency cannot be determined in mechanism, you need to run a modal analysis in Mechanica.

 

[Tunalover]

Sounds like a straightforward Roark hand calculation will give a decent answer.


Tunalover

 

[flyerfly]

You have to use mechanica to do this. First just put the assembly into a modal analysis. Find the first 6 or so modes (or until you get up to and a little past the frequency of the motor in Hz). Then to find out what will actually happen at that frequency you need to take the output from the modal analysis and put a forcing function on it F*cos(wt) that will drive it at the frequency of the motor where F is the force that will come from the motor being out of balance etc.

The amplitude you get out the simple modal analysis is NOT real unless you put the forcing function into it.

Hope this helps.