Automotive Amplitude based frequency response simulation in Abaqus

AI Thread Summary
The discussion centers on setting up an amplitude-based frequency response simulation in Abaqus, specifically applying a displacement of 0.2 mm at a concerned frequency of 100 Hz. It is noted that Abaqus does not allow nonzero displacements as boundary conditions in mode-based dynamic response procedures, meaning users must use base motion or apply a force instead. The original poster seeks guidance on how to configure the analysis and whether amplitude can be applied in steps over a frequency range of 0-200 Hz. A suggestion to search for existing resources on Abaqus frequency analysis is provided. Ultimately, the user decides to proceed with applying a force for the simulation.
Sam George
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Enforce displacement in Frequency Response Simulation
Hi,

I have inputs like displacement of a driving mechanism and then the frequency of concern .

Displacement: 0.2 mm
Concerned Frequency: 100 Hz


I would like to evaluate a part with the input displacement applied to a node and not as base excitation.
It can be sweep over the frequency range 0-200Hz

How do we set it up in Abaqus, can we give amplitude in steps over the frequency range?

Please guide me with a link or syntax on how to proceed with the analysis setup.

Regards,
Sam George
 
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Here’s a quote from Abaqus documentation (chapter about SSD analyses):

It is not possible to prescribe nonzero displacements and rotations directly as boundary conditions in mode-based dynamic response procedures. Therefore, in a mode-based steady-state dynamic analysis, the motion of nodes can be specified only as base motion; nonzero displacement or acceleration history definitions given as boundary conditions are ignored, and any changes in the support conditions from the eigenfrequency extraction step are flagged as errors.

So you have to either use a base motion BC or apply a force instead.
 
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FEAnalyst said:
Here’s a quote from Abaqus documentation (chapter about SSD analyses):

It is not possible to prescribe nonzero displacements and rotations directly as boundary conditions in mode-based dynamic response procedures. Therefore, in a mode-based steady-state dynamic analysis, the motion of nodes can be specified only as base motion; nonzero displacement or acceleration history definitions given as boundary conditions are ignored, and any changes in the support conditions from the eigenfrequency extraction step are flagged as errors.

So you have to either use a base motion BC or apply a force instead.
Thanks for the reply, I think I will have go with using Force.
 
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