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large deformation

A solid-shell model of hard-magnetic soft materials

Submitted by Fan Xu on

Hard-magnetic soft materials (HMSMs) consisting of an elastomer matrix filled with high remnant magnetic particles can exhibit flexible programmability and rapid shape changing under non-contact activation, showing promising potential applications in soft robotics, biomedical devices and flexible electronics. Precise predictions of large deformations of hard-magnetic soft materials would be a key for relevant applications.

Extrusion, slide, and rupture of an elastomeric seal

Submitted by Zhengjin WANG on

Elastomeric seals are essential to two great technological advances in oilfields:  horizontal drilling and hydraulic fracturing.  This paper describes a method to study elastomeric seals by using the pressure-extrusion curve (i.e., the relation between the drop of pressure across a seal and the volume of extrusion of the elastomer).  Emphasis is placed on a common mode of failure found in oilfields:  leak caused by a crack across the length of a long seal.  We obtain an analytical solution of large elastic deformation, which is analogous to the Poiseuille flow of vi

Large Deformation - Definition of total work energy density

Submitted by rajan_prithivi on
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Like we have the elastic strain energy density for small deformations  defined as 0.5* σ :e  .

Is the equation PK2:E valid for the total work energy density for elastoplastic regimes ? If not, what would be a valid equation for total energy density ?

How can we decompose total work density into elastic work and plastic work densities for a large deformation case.

Where,

PK2 is the second piola kirchoff stress tensor

E is the Green-Lagrange strain tensor

 

Thanks,

Prithivi

 

 

Shape Bifurcation of a Spherical Dielectric Elastomer Balloon under the Actions of Internal Pressure and Electric Voltage

Submitted by Xudong Liang on

Under the actions of internal pressure and electric voltage, a spherical dielectric elastomer balloon usually keeps a sphere during its deformation, which has also been assumed in many previous studies. In this article, using linear perturbation analysis, we demonstrate that a spherical dielectric elastomer balloon may bifurcate to a nonspherical shape under certain electromechanical loading conditions.

How to get the update the local material coordinate in large deformation for hyperelasitc rubber-like materials?

Submitted by Jiang Chen on

Hello, 

I want to ask things about the updation of local material coordinate in large deformation. 

Does there exist two ways for this?

1. Polar decomposition of Gradient Deformation Tensor F to get the rotation tensor.

2. Update each basis vector of local material coordinate system using modified Gradient Deformation Tensor F_bar = F*J^(-1/3).

What I cared about is the second method, is the second method available?

Wish someone could help me, : ). Thanks!! 

PhD studentship position on "modelling of surface defects transformation in hot rolling of steel"

Submitted by Ghadbeigi on

a PhD student ship is available for UK/EU nationals (ONLY) to develop a Finite Element model of the rolling
operation to predict the behaviour of surface defects on the rolled
material during hot rolling of steels. The effects of geometrical parameters along with the material
properties and the rolling geometry, such as bite angle, on the behaviour of
the surface defects during rolling will be investigated. The
project is partially funded by Tata Steel Europe,