Trying to find frequency response of an expander on an electromagnetic shaker head.

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Attached is a COMSOL file that is my first attempt at finding the frequency response of an expander head that is attached to my new HBK v722 electromagnetic shaker.

I have also attached a 1 page PDF that explains in photos what I am trying to do.

Simply put, I have tried to approximate the frequencies at which my expander head will vibrate, and the RMS magnitude of said vibration at each modal frequency.

I did so by applying a harmonic (sinusoidal) force at the bottom of the expander (where the shaker face is) while holding the bolt clamping surfaces fixed in space.

Not exactly reality, but I do seem to keep getting results consistent with tests.

But I feel that I am setting myself up for hurt later, and seek advice on best methods.

I do not care about forces in the bolts, just what is happening in the thing I am shaking…in this case the expander head.

0 Replies Last Post Jan 20, 2022, 12:24 p.m. EST
COMSOL Moderator

Hello John Baxley

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