Negative Modal Frequencies

- October 18, 2022 at 9:57 am
  
  drwilkes7
  Subscriber
  
  Has anybody encountered the warning message below when conducting a damped modal analysis in ANSYS 2021 R2?
  The model consists of a rectangular plate suspended by body-ground longitudinal springs attached at the corners. The springs include longitudinal damping and the plate material also has material dependent-damping (damping ratio). Removing the longitudinal damping from the springs appears to alleviate the issue, while the material damping doesn't seem to change the result.
- October 19, 2022 at 2:28 pm
  
  Chandra Sekaran
  Ansys Employee
  
  please repost the warning message
  - October 19, 2022 at 3:49 pm
    
    drwilkes7
    Subscriber
    
    Thank you very much Chandra Sekaran for replying. The warning message is below:
    Of course, changing the Frequency Display from 'Program Controlled' to 'All' will stop the actual warning message. My real interest is in what might cause non-conjugate pairs of complex frequencies to be calculated by the Full Damped Solver.
    
    Any help would be greatly appreciated.

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