Stiffness/Damping coefficients at nonsynchronous rotational speed

[VibFrank]

Hy,

the calculated stiffness- and damping values for plain cylindrical journal bearings are valid only for forces with rotational speed. How do they change with much higher frequencies (10x rotational speed) ?

Thanks for your comments
Frank

 

[WCFoiles]

Plain journal bearings are modeled with constant coefficients for stiffness and damping(not freq. dependent). They are generally good for non-synchronous. If the frequency were extremely high, there may not be confirming test data, but otherwise this is what tests have shown.


Regards,

Bill

 

[sms]

We are typically more worried about speeds less than running speed due to instability. I am curious why your are interested 10X.

Typically above a certain speed the curves flatten out and the KXX and KXY coefficients stay the same...

"Why don't you knock it off with them negative waves? Why don't you dig how beautiful it is out here? Why don't you say something righteous and hopeful for a change?" Oddball, "Kelly's Heros" 1970

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