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critical speed for vertical shaft

critical speed for vertical shaft

critical speed for vertical shaft

I have a problem as shown in attachment,here a vertical shaft is powered by a motor.
at the top of the shaft a circular disk is fixed weigh approximately 3 kg.
the shaft runs at 3000rpm and motor power is 0.75 hp.

Iam intrested to know the critical speeds within the working rpm range.( first ,second and may be more critical speeds).

i would be obliged if somebody helps out.

RE: critical speed for vertical shaft

There is at least one crucial piece of information missing, namely what sort of boundary condition the motor represents. I assume that your textbook assumes fixed, radially.

If you were only interested in the first bending mode I'd suggest Rayleigh_Ritz, since the mode shape is obvious, but i must admit for the higher order modes I've forgotten how to do it other than FEA.


Greg Locock

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RE: critical speed for vertical shaft

thanks sir for useful information.


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