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Damping in Transient

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Hi,

It seems that in transient solid mechanics the damping is not taken into account. I tried to introduce a structural loss factor but whatever the value i put in the subnode "Damping" i still have the same results.
I also introduced a complex young modulus E*=E(1+i*eta_s) but i got the same results. Did you face this problem?? i'am on Comsol 4.2 and 4.2a
In frequency domaine evrything is ok!

Thanks


4 Replies Last Post Jun 24, 2012, 5:50 p.m. EDT

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Posted: 1 decade ago Mar 1, 2012, 8:56 a.m. EST
Hi,

For transient models you must either use Rayleigh Damping factors (alpha and beta) or use viscoelastic material and add damping there via relaxation time.

Damping factors only work for frequency domain studies.

Rob
Hi, For transient models you must either use Rayleigh Damping factors (alpha and beta) or use viscoelastic material and add damping there via relaxation time. Damping factors only work for frequency domain studies. Rob

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Posted: 1 decade ago Jun 24, 2012, 6:15 a.m. EDT
Thank you dear Robert.

Thank you dear Robert.

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Jun 24, 2012, 8:26 a.m. EDT
Hi

you find much more in the new 4.3 doc, on structural, and non linear materials, and time domain damping is also possible, in alpha, beta, but not isotropic ,check the equations of your physics when you switch the solver type

And check carefully the doc (PDF files), and v4.3 has been nicely updated

--
Good luck
Ivar
Hi you find much more in the new 4.3 doc, on structural, and non linear materials, and time domain damping is also possible, in alpha, beta, but not isotropic ,check the equations of your physics when you switch the solver type And check carefully the doc (PDF files), and v4.3 has been nicely updated -- Good luck Ivar

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Posted: 1 decade ago Jun 24, 2012, 5:50 p.m. EDT
Hello Ivar,

That is very interesting, thank you.

Doudou.
Hello Ivar, That is very interesting, thank you. Doudou.

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