A variational constitutive framework for the nonlinear viscoelastic response of a dielectric elastomer

Handle URI:
http://hdl.handle.net/10754/562408
Title:
A variational constitutive framework for the nonlinear viscoelastic response of a dielectric elastomer
Authors:
Khan, Kamran; Wafai, Husam; El Sayed, Tamer S.
Abstract:
We formulate a variational constitutive framework that accounts for nonlinear viscous behavior of electrically sensitive polymers, specifically Dielectric Elastomers (DEs), under large deformation. DEs are highly viscoelastic and their actuation response is greatly affected in dynamic applications. We used the generalized Maxwell model to represent the viscoelastic response of DE allowing the material to relax with multiple mechanisms. The constitutive updates at each load increment are obtained by minimizing an objective function formulated using the free energy and electrostatic energy of the elastomer, in addition to the viscous dissipation potential of the dashpots in each Maxwell branch. The model is then used to predict the electromechanical instability (EMI) of DE. The electro-elastic response of the DE is verified with available analytical solutions in the literature and then the material parameters are calibrated using experimental data. The model is integrated with finite element software to perform a variety of simulations on different types of electrically driven actuators under various electromechanical loadings. The electromechanical response of the DE and the critical conditions at which EMI occurs were found to be greatly affected by the viscoelasticity. Our model predicts that under a dead load EMI can be avoided if the DE operates at a high voltage rate. Subjected to constant, ramp and cyclic voltage, our model qualitatively predicts responses similar to the ones obtained from the analytical solutions and experimental data available in the literature. © 2012 Springer-Verlag Berlin Heidelberg.
KAUST Department:
Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division; Physical Sciences and Engineering (PSE) Division
Publisher:
Springer Nature
Journal:
Computational Mechanics
Issue Date:
10-Nov-2012
DOI:
10.1007/s00466-012-0815-6
Type:
Article
ISSN:
01787675
Sponsors:
This work was funded by the KAUST baseline fund. The authors would also like to thank the Research Computing team and KAUST IT for their technical support.
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division; Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorKhan, Kamranen
dc.contributor.authorWafai, Husamen
dc.contributor.authorEl Sayed, Tamer S.en
dc.date.accessioned2015-08-03T10:37:08Zen
dc.date.available2015-08-03T10:37:08Zen
dc.date.issued2012-11-10en
dc.identifier.issn01787675en
dc.identifier.doi10.1007/s00466-012-0815-6en
dc.identifier.urihttp://hdl.handle.net/10754/562408en
dc.description.abstractWe formulate a variational constitutive framework that accounts for nonlinear viscous behavior of electrically sensitive polymers, specifically Dielectric Elastomers (DEs), under large deformation. DEs are highly viscoelastic and their actuation response is greatly affected in dynamic applications. We used the generalized Maxwell model to represent the viscoelastic response of DE allowing the material to relax with multiple mechanisms. The constitutive updates at each load increment are obtained by minimizing an objective function formulated using the free energy and electrostatic energy of the elastomer, in addition to the viscous dissipation potential of the dashpots in each Maxwell branch. The model is then used to predict the electromechanical instability (EMI) of DE. The electro-elastic response of the DE is verified with available analytical solutions in the literature and then the material parameters are calibrated using experimental data. The model is integrated with finite element software to perform a variety of simulations on different types of electrically driven actuators under various electromechanical loadings. The electromechanical response of the DE and the critical conditions at which EMI occurs were found to be greatly affected by the viscoelasticity. Our model predicts that under a dead load EMI can be avoided if the DE operates at a high voltage rate. Subjected to constant, ramp and cyclic voltage, our model qualitatively predicts responses similar to the ones obtained from the analytical solutions and experimental data available in the literature. © 2012 Springer-Verlag Berlin Heidelberg.en
dc.description.sponsorshipThis work was funded by the KAUST baseline fund. The authors would also like to thank the Research Computing team and KAUST IT for their technical support.en
dc.publisherSpringer Natureen
dc.subjectDielectric elastomersen
dc.subjectElectroactive materialsen
dc.subjectFinite Viscoelasticityen
dc.subjectHyperviscoelasticityen
dc.subjectVariational Modelen
dc.titleA variational constitutive framework for the nonlinear viscoelastic response of a dielectric elastomeren
dc.typeArticleen
dc.contributor.departmentComputer, Electrical and Mathematical Sciences and Engineering (CEMSE) Divisionen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalComputational Mechanicsen
kaust.authorKhan, Kamranen
kaust.authorWafai, Husamen
kaust.authorEl Sayed, Tamer S.en
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