Propeller-induced structural vibration and normal modes

[MBD26]

To simplify the situation I'm trying to model, imagine you have a cantilever beam with a propeller oriented perpendicular to the length of the beam at the free end. I want to ensure that the prop vibration won't excite any of the normal modes of the beam. If I run normal mode analysis on the beam and find that the normal mode frequencies are all below the standard operating frequencies of the motor (rps for trim flight, etc), does that mean we're in the clear? Or am I thinking about this wrong

Thanks

 

[rb1957]

you need to consider the blade passing frequency ... prop rpm*(number of blades)

Quando Omni Flunkus Moritati

 

[GregLocock]

..and harmonics thereof.



Cheers

Greg Locock


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