Steady-state dynamics modal response question

[ovdschaft]

Hello,

I would like to calculate a frequency response for a vibration test, based on eigenfrequencies, for 3 assembled cover components of a car display module.
My analysis consists of the following steps:
1.Eigenfrequency calculation (modes 1-20, min freq: 1 Hz)
2.Steady-state dynamics,modal response: 1-500 Hz, 500 freq points, bias=1, scale=linear, modal damping.

Concerning the set parameters in step 2, I expect Abaqus to calculate the response for 1,2,3, ..., 500 Hz. This is not the case. The increments are variable (between 0 - 0.5 Hz).
Why is this?

Thanks in advance,
Oscar van der Schaft
Graduate student Mech. eng.

 

[igortz22]

It seems that you probably use the default option
INTERVAL=EIGENFREQUENCY
Abaqus calculates the responce for each eigenfrequency and 498 points in between (in your case- 1Hz, next 498 points, first eigenfrequncy, next 498 points, second eigenfrequency etc.).

You should use INTERVAL=RANGE to get 500 uniformly distributed frequency points.
Regards
Igor