Modal analysis error

- March 25, 2020 at 2:09 pm
  
  dardhruv
  Subscriber
  
  Hi,
  
  I am doing Modal acoustic analysis, and I got this warning:
  
  *** WARNING *** CP = 0.969 TIME= 14:53:20
  
  Element shape checking is currently inactive. Issue SHPP,ON or SHPP,WARN to reactivate, if desired.
  
  *** WARNING *** CP = 1.281 TIME= 14:53:21
  
  The ending frequency 100000000 (Hz) in MODOPT command may be too high
  
  for acoustic modal analysis. It is recommended to use 1000000 (Hz) as
  
  the ending frequency.
  
  *** WARNING *** CP = 2.172 TIME= 14:53:22
  
  Coefficient ratio exceeds 1.0e8 - Check results.
  
  *** WARNING *** CP = 2.391 TIME= 14:53:22
  
  The damped eigensolver did not find a damping matrix. For efficiency,
  
  please use an eigensolver that does not consider damping to solve this
  
  model.
  
  *** WARNING *** CP = 3.844 TIME= 14:53:23
  
  The eigenproblem is ill-conditioned (relative residual from test linear
  
  solve: 1.137193E-03). The accuracy of the solution may not be
  
  satisfactory. Modifying the initial value of the frequency shift
  
  (FREQB in the MODOPT command) or changing the boundary conditions of
  
  the model might solve the problem.
  
  *** WARNING *** CP = 31.172 TIME= 14:53:51
  
  Fewer modes than the requested number of modes ( 12 ) were computed.
  
  The range specified (FREQB= 0, FREQE= 100000000) contains only 0
  
  modes.