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Modeling nonlinear lumped viscous damper

Posted Aug 30, 2024, 5:24 a.m. EDT 0 Replies

Filippo Tosato

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Hello, i m trying to model a plate where I attach some particle dampers modelled as a equivalent nonlinear viscous damping coefficient(Ceq) and a mass(Md). (lumped damper and mass).(see picture) The problem is that the equivalent nonlinear viscous damping coefficient depend on: levels of excitation (frequency ) ,the excitation velocity amplitude and the second invariant deviatoric stress. My question is: 1 how can i add Md and Ceq to the equation of motion Ma+Ks+Cv=F? My idea is using lumped mass-spring-damper physics but since Ceq is a big and complex equation depending on the above parameters should i instead PDE module (weak form ). 2) should i first study the plate without the damper and use the excitation velocity amplitude and the second invariant deviatoric stress result to add them to the full system? PS: i have solid mechanical structure physics coupled with pressure acoustic(frequency ).

i want to study the pressure attenuation in the air of the vibration of plate in frequency domain due to a point load.

I attach scheme of the plate plus dampers and equation that i have to implement. thanks in advanced

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