In this paper, the effect of suspended particles on thermal convection in an incompressible Rivlin-Ericksen elastico-viscous fluid in a porous medium is considered. For the porous medium, the Brinkman model is employed. By applying a normal mode analysis method, the dispersion relation has been derived and solved analytically. It is observed that the medium permeability, suspended particles, gr...

It is previously known that under inflation alone a spherical rubber membrane balloon may bifurcate into a pear shape when the tension in the membrane reaches a maximum, but the existence of such a maximum depends on the material model used: the maximum exists for the Ogden model, but does not exist for the neoHookean, Mooney-Rivlin or Gent model. This paper discusses how such a situation is ch...

Static deflection as well as free and forced nonlinear vibration of thin square plates made of hyperelastic materials are investigated. Two types of materials, namely rubber and soft biological tissues, are considered. The involved physical nonlinearities are described through the Neo-Hookean, Mooney-Rivlin, and Ogden hyperelastic laws; geometrical nonlinearities are modeled by the Novozhilov n...

Atomic force microscopy is an established technique for probing the local elastic properties of materials at submicron scales. In some cases, linear elastic contact theories based on Hertzian and adhesive contact mechanics suffice to model the indentation process. However, at the large strains that are common in many nanoindentation experiments, the linear models become invalid. A force-indenta...

This practice and experience paper describes a robust C++ implementation of several nonlinear solid 3D deformable object strategies commonly employed in computer graphics, named the Vega FEM simulation library. Deformable models supported include co-rotational linear FEM elasticity, Saint-Venant Kirchhoff FEM model, mass-spring system, and invertible FEM models: neo-Hookean, Saint-Venant Kirchh...

The hydromagnetic instability of the plane interface between two uniform, superposed and streaming Rivlin-Ericksen viscoelastic fluids through porous medium is considered. The case of two uniform streaming fluids separated by a horizontal boundary is studied. It is observed, for the special case where perturbations in the direction and transverse direction of streaming are ignored, that the sys...

This paper presents a biomechanical model of the face to simulate orofacial movements in speech and non-verbal communication. A 3D finite element model, based on medical images of a subject, is presented. A hyperelastic Mooney-Rivlin constitutive law accounts for the non-linear behaviour of facial tissue. Muscle fibres are represented by piece-wise uniaxial tensile element that generate force. ...

In this paper, we propose a finite-element scheme for solving numerically the equations of a transient two dimensional grade-two fluid non-Newtonian Rivlin-Ericksen fluid model. This system of equations is considered an appropriate model for the motion of a water solution of polymers. As expected, the difficulties of this problem arise from the transport equation. As one of our aims is to deriv...

Understanding of the dynamic behaviour of the levator ani is important to the assessment of pelvic floor dysfunction. Whilst shape modelling allows the depiction of 3D morphological variation of the levator ani between different patient groups, it is insufficient to determine the underlying behaviour of how the muscle deforms during contraction and strain. The purpose of this study is to perfor...