Finite element simulation of viscoelastic flow

Viriyayuthakorn, M.; Caswell, Bruce

doi:10.1016/0377-0257(80)80005-x

Cited by 135 publications

(23 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Other than the studies referred to above, important work on the tracking problem has been carried out by Viriyayuthakorn and Caswell [9] and Court et al [10]. However, their results do not seem to be as exact or as general as the present ortes.…”

Section: Introductionmentioning

confidence: 91%

Calculation of strain histories in Protean coordinate systems

Adachi

1983

Rheol Acta

View full text Add to dashboard Cite

Integral equations for the relative deformation gradient tensors are solved to give analytical expressions which involve velocities and velocity gradients along streamlines.For some Protean coordinate systems, metric tensors are presented, and deformation gradients and strain histories are calculated.The results are tested for two types of flow: rotational shearing flow and extensional flow. They are found to give the existing exact relations for the Finger strain tensor.

show abstract

Section: Introductionmentioning

confidence: 91%

Calculation of strain histories in Protean coordinate systems

Adachi

1983

Rheol Acta

View full text Add to dashboard Cite

show abstract

“…The velocity and pressure field update scheme we use is based upon that of Viriyayuthakon and Caswell [37]. The method we use here contains a small, but valuable, modification to the method detailed in ref [5].…”

Section: Updating the Flow Fieldsmentioning

confidence: 99%

A modification of the convective constraint release mechanism in the molecular stress function model giving enhanced vortex growth

Olley

Wagner

2006

Journal of Non-Newtonian Fluid Mechanics

View full text Add to dashboard Cite

The molecular stress function model with convective constraint release (MSF with CCR) constitutive model [J. Rheol. 45 (2001), 1387] is capable of fitting all viscometric data for IUPAC LDPE, with only two adjustable parameters (with difference found only on reported "steady-state" elongational viscosities). The full MSF with CCR model is implemented in a backwards particle-tracking implementation, using an adaptive method for the computation of relative stretch that reduces simulation time many-fold, with insignificant loss of accuracy. The model is shown to give improved results over earlier versions of the MSF (without CCR) when compared to well-known experimental data from White and Kondo [J. non-Newt. Fluid Mech., 3 (1977), 41]; but still to under-predict contraction flow opening angles. The discrepancy is traced to the interaction between the rotational dissipative function and the large stretch levels caused by the contraction flow. A modified combination of dissipative functions in the constraint release mechanism is proposed, which aims to reduce this interaction to allow greater strain hardening in a mixed flow. The modified constraint release mechanism is shown to fit viscometric rheological data equally well, but to give opening angles in the complex contraction flow that are much closer to the experimental data from White and Kondo. It is shown (we believe for the first time) that a constitutive model demonstrates an accurate fit to all planar elongational, uniaxial elongational and shear viscometric data, with a simultaneous agreement with this well-known experimental opening angle data. The sensitivity of results to inaccuracies caused by representing the components of the deformation gradient tensor to finite precision is examined; results are found to be insensitive to even large reductions in the precision used for the representation of components. It is shown that two models that give identical response in elongational flow, and a very similar fit to available shear data, give significantly different results in flows containing a mix of deformation modes. The implication for constitutive models is that evaluation against mixed deformation mode flow data is desirable in addition to evaluation against viscometric measurements.

show abstract

“…26 To introduce an implicit method, the force-balance of notional small-strain stresses, given by r Á G e G u þ Be B u ð Þ , is subtracted from each side of the equation. G is a shear modulus comparable to the low-strain shear modulus of the nonlinear constitutive model, and B is a bulk modulus.…”

Section: Finite Element Solution Methodsmentioning

confidence: 99%

A multiprocess eyring model for large strain plastic deformation

Olley

Sweeney

2010

J of Applied Polymer Sci

View full text Add to dashboard Cite

A multiprocess Eyring model is developed with a particular aim of predicting the localized instability occurring in ''necking'' polymers when cold-drawn. Differences from using single and multiple Eyring processes are examined using a published data-set for polypropylene test pieces; it is shown that a four Eyring process model can simultaneously fit both necking stretch ratio and draw force data for uniaxial stretching, whereas with a single process only one measurement could be fitted accurately. The multi process Eyring model is shown to give significantly more accurate predictions than a necking hyperelastic model. The multiprocess model is assessed against the same material undergoing a complex constant-width elongation. It is shown that agreement is quantitatively good for both drawing force and surface deformation, with some minor differences in transverse force and surface stretch. A pronounced intermittent stretching pattern that is seen on the experimental test piece is replicated by the multiprocess Eyring simulation, but is absent using the hyperelastic model. A method is described to deform a photograph of the original specimen according to a finite element solution. The method is shown to give a clear indication of the accuracy of the model in predicting final form.

show abstract

Finite element simulation of viscoelastic flow

Cited by 135 publications

References 10 publications

Calculation of strain histories in Protean coordinate systems

Calculation of strain histories in Protean coordinate systems

A modification of the convective constraint release mechanism in the molecular stress function model giving enhanced vortex growth

A multiprocess eyring model for large strain plastic deformation

Contact Info

Product

Resources

About