Vortex Shedding; STS-1-2006

[mark416]

Hello All;

To calculate equivalent static vortex loading, ASME STS-1-2006 uses a "normalized mode shape". How does one calculate this "normalized mode shape". I use Risa to calculate the natural frequency and mode shapes of the stack, but how do you make the mode shape into a normalized mode shape? Thanks.
Mark416.

 

[hacksaw]

there are at least two normalization methods. one does it on a mass x deflection^2 basis, the other just on a deflection^2 basis, the ij subscripts have been ignored...

you have to look at their analysis to sort it out. just text book issues, but you have to be consistent with what they've done.

good luck

 

[mark416]

Just to make sure that I got it right (with out a text book), normalized mode shape = n/{sum(mass*n^2)}^2 where n=mode shape. Is this anything close to it.
Thanks,
Mark.