phase of load for specturm analysis? 1

[stevesmiles1]

Attempting a MPRS analysis...

I would like to apply force loads for spectrum analysis. They are derived from dfft of time-based data. The dfft data is a complex number, so I have magnitude and phase. Now I would like to apply this frequency-based load data to a structural model.

Is it possible to enter complex number for the SV values? Or is there another method to account for phase when doing spectral analysis???

thanks,
-steve

 

[Drej]

Don't think you can account for the phase in response spectrum analyses, simply because all loads are assumed to be applied in-phase (linear system approach). There is no mention of phase in any of the SV or SVTYP commands in the help file.


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[GregLocock]

In a linear system you can just add the phase of the input signal at any point in the analysis. However, it may be that your program does not give you phase in the transfer function, so that won't work.


Cheers

Greg Locock

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