Learning Forum

[rani.a]

Hi,

I am performing a Modal analysis derived from the static structural results attained.

I have given a Frequency minimum range 7Hz and maximum range 200 Hz in the analysis settings.

The solving is taking longer than expected for the high performance PC i have(PS: running the simulation with 12 cores). Also, the solution gets stuck at 90% for almost 1+ hours and does not move forward(attached below the image for reference).
It proceeds from 0-40% in less than a minute. 40-53% in 30 mins, 53-72% in 15 mins and 72-90% in the next 15 mins and gets stuck there

 

I am using Ansys 2024 R2 version

I have not got any info/warnings/errors during the solution.
Is there any general reason behind this solution getting stuck? What can be the solution for this issue?

[Erik Kostson]

Hi

First run a simple analysis on a steel cube/beam just to check that all is ok.

Not sure, but you seem to have lots of very low freq. (1E-6 Hz)? if that is the case it will be a huge amount of modes untill 7 Hz if they are so low - check material, contacts, constraints, properties etc.

All the best

 

Erik

[rani.a]

Hi Erik,

Thank you for the response.

Yes, the requirement for my vibration analysis is between 7Hz to 200Hz. The static structural solution has been successful, yet this is the issue with the Modal.

[Erik Kostson]

 

Hi

As we said:

First run a simple analysis on a steel cube/beam (say resonable dimensions) just to check that all is ok.

Erik

 

[rani.a]

Hi Erik,

Sure, i will try out a sample model for both static structural and modal analysis and get back.

Meanwhile, you had mentioned about 1E-6Hz being very low. Was it the values on the RHS your were referring to? If so, they are the mass values, not frequency. Probably the mass of nuts & washers in the assembly. 

[Erik Kostson]

Hi

Yes was not sure what these values are - but I would say try a simple model frist to make sure all is ok.

Erik

[rani.a]

Hi,
I have found an alternate solution using Harmonic Analysis.
A quick doubt here, I want to know the parameters for the X-Axis and Y-Axis of the Phase Response curve