Viscous energy

[lolitapr]

Dear all,

I want to be able to calculate the viscous energy, absorbed energy, input energy,etc. But I do not know how to either extract the damping matrix or the velocity. Is there a way to do this?

Thanks!!!

[fmk]

you cannot extract the damping matrix.
can you write what it is you want in matrix terms, either from an ele point of view or total system point of view.

[lolitapr]

Ok. The following is the general energy formulation:

Ek(t)+Evd(t) +Ea(t)=Ein(t) +Est(t)

where:

Ek(t)=relative kinetic energy at time t and is:

(1/2){(velocity transpose)}(M){(velocity)}

Evd(t)=energy dissipated energy by viscous damping

integral{velocity transpose)}(C){dx}

Ea(t)=is the absorbed energy

integral({dx}{Fr})

Ein(t)=relative input energy

-integral{dx}(M){r}accel ground motion

I want to be able to calculate each of these terms. Thanks for your help on this matter.