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determination of Q factor

Shyamsananth Madhavan

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Hi
I just finished tutorial of determination of Q factor of gryoscope.
I am working on Resonant Accelerometers.

In tutorial , u have provided alternate method
Q=?0/2? = abs(imag?/2real?).

I tried this for my accelerometer ... it gave no real part of Eigen Frequency. Only imag part is available. As a result Q factor becomes NaN.
I tried with a cantilever , hard luck Q is NaN.


Can anyone elaborate this method ? I need to find the Q for my accelerometer structure.

Steps I took
Freq response module ---- applied Body load --- In scalar variables change Freq_smps to lambda/2*pi*i ---- solve in eigenfrequency solver under Freq Response Analysis type....


I think my steps are right as per the Tutorials.


Please Help me out...

1 Reply Last Post 2010年6月18日 GMT-4 01:32
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2010年6月18日 GMT-4 01:32
Hi

I cannot reply directly on your examples, but do not forget that a "Q" factor is directly linked a loss factor, you how have you defined the losses in your model ? Do you have material losses, electric losses, (and numerical losses) these all contribute and should be present and quantified.

Good luck
Ivar
Hi I cannot reply directly on your examples, but do not forget that a "Q" factor is directly linked a loss factor, you how have you defined the losses in your model ? Do you have material losses, electric losses, (and numerical losses) these all contribute and should be present and quantified. Good luck Ivar

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