1 Reply Latest reply on Oct 4, 2011 11:39 AM by Matthew Jackson

    Frequency modes different based on number requested

    Peter Holmi

      Does anyone know the reason that the resonant frequency results are dependant on the number of requested frequencies?  I am running an assembly through several studies and found that if I choose the number of frequencies at 6 rather than 3, the resultant modes are nearly identical whether the mesh is nearly course or fine.  However, if I request only 3 modes, the convergence takes longer the the resultant frequencies differ by 2% from the request for 6 modes.  Also, with a request for 3 modes, the mesh quality affects the results to a larger degree.  For the study, I am not interested in the results above 500 Hz; however, I am interested in accurate, repeatable results and it seems that I need to run the higher frequencies to satisfy SolidWorks.  SW2010, SP4

        • Re: Frequency modes different based on number requested
          Matthew Jackson

          The frequencies that you get will be dependant on the amount of mass participation within the FE model. To check the amount of mass right click results > mass participation.

           

          A resonable amount is > 80% (0.80). If less mass is participating then the results will not be accurate, to increase the mass then increase the amount of frequencies you are solving for.

           

          If you can post the models then I can take a look.