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An efficient nonlinear solver and convergence analysis for a viscoplastic flow model [article]

Sara Pollock and Leo G. Rebholz and Duygu Vargun
2021 arXiv   pre-print
An efficient nonlinear solver for the discrete model is then proposed and analyzed.  ...  This paper studies a finite element discretization of the regularized Bingham equations that describe viscoplastic flow.  ...  but with AA (and in particular with m ≥ 5), it can be an effective and efficient solver.  ... 
arXiv:2108.08945v1 fatcat:mz32gs3prrb6hi44pf7sesfy5y

Modeling of metal forming processes: implementation of an iterative solver in the flow formulation

Dolores Demarco, Eduardo N. Dvorkin
2001 Computers & structures  
In this paper we discuss the implementation of an iterative solver for the efficient solution of the resulting equation systems.  ...  Rigid -viscoplastic models of metal forming processes are mathematically formulated as nonlinear Stokes problems: incompressible ßows with variable viscosity, function of the point velocities.  ...  Introduction The use of rigid -viscoplastic material models for the simulation of bulk metal forming processes (ßow formulation) has proven to be a very efficient and reliable engineering tool and it is  ... 
doi:10.1016/s0045-7949(01)00118-3 fatcat:3i7ll6r2xrdgriubed2cf6ftpq

Progress in numerical simulation of yield stress fluid flows

Pierre Saramito, Anthony Wachs
2017 Rheologica Acta  
In the first part of this paper, we review the classical numerical methods for the solution of the non-smooth viscoplastic mathematical models, highlight their advantages and drawbacks, and discuss more  ...  In the second part, we present and analyze a variety of applications and extensions involving viscoplastic flow simulations: yield slip at the wall, heat transfer, thixotropy, granular materials, combining  ...  Duvaut and Lions (1976) also provided a theoretical analysis for Poiseuille flows and flows in a reservoir.  ... 
doi:10.1007/s00397-016-0985-9 fatcat:p5mqpabfdfbqniw7vrq7dtfkle

A damped Newton algorithm for computing viscoplastic fluid flows

Pierre Saramito
2016 Journal of Non-Newtonian Fluid Mechanics  
For the first time, a Newton method is proposed for the unregularized viscoplastic fluid flow problem.  ...  Performances are enhanced by using the inexact variant of the Newton method and, for solving the Jacobian system, by using an efficient preconditioner based on the regularized problem.  ...  Acknowledgment The author would like to thank the anonymous reviewers for constructive comments that help improving the redaction of this paper.  ... 
doi:10.1016/j.jnnfm.2016.05.007 fatcat:igp6apcpv5ha3fin4unztav6qy

Four-Field Finite Element Solver and Sensitivities for Quasi-Newtonian Flows

N. Martin, J. Monnier
2014 SIAM Journal on Scientific Computing  
Bidimensional numerical experiments are performed on two realistic situations of gravity flows: an experimental viscoplastic steady wave and a continental glacier.  ...  A computationally efficient finite element algorithm for power law fluid is elaborated in view of extensive direct and inverse simulations.  ...  We want to thank Benoit Legrésy (LEGOS) for his data on the Mertz glacier and Ronan Madec (IMT) for his help on the development of the adjoint code.  ... 
doi:10.1137/130914887 fatcat:tubrecafjfhxdbljgjgayyibnq

Advances in the simulation of viscoplastic fluid flows using interior-point methods

Jeremy Bleyer
2018 Computer Methods in Applied Mechanics and Engineering  
We present a primal-dual interior point algorithm for the resolution of steady-state viscoplastic fluid flows formulated as a conic optimization problem.  ...  The yield surfaces are shown to be accurately predicted and various examples ranging from channel flows to three-dimensional flows through a porous medium demonstrate its efficiency.  ...  In the present paper, we follow the general idea of the IPM, as usually implemented in IPM solvers, to derive an efficient algorithm for computing viscoplastic flows.  ... 
doi:10.1016/j.cma.2017.11.006 fatcat:r6in5abypzdstbgvn6t6y3p3h4

Thermo-micro-mechanical simulation of bulk metal forming processes [article]

S. Amir H. Motaman, Konstantin Schacht, Christian Haase, Ulrich Prahl
2019 arXiv   pre-print
The newly proposed microstructural constitutive model for polycrystal viscoplasticity in cold and warm regimes (Motaman and Prahl, 2019), is implemented as a microstructural solver via user-defined material  ...  Then, the viability of this approach is shown for (TMM-) FE simulation of an industrial multistep warm forging.  ...  The authors also wish to thank "Schondelmaier GmbH Presswerk" for performing experimental forging.  ... 
arXiv:1810.11670v2 fatcat:jiitoeg5bndvpm345d2unwo5pe

An Iterative Method for the Stokes-Type Problem with Variable Viscosity

Piotr P. Grinevich, Maxim A. Olshanskii
2009 SIAM Journal on Scientific Computing  
We build a special block preconditioner for the discrete system of equations and perform an analysis revealing its properties; the theoretical analysis is based on the weighted Nečas inequality.  ...  In particular, the general analysis is applied to the linearized equations of the regularized Bingham model of viscoplastic fluid.  ...  However, a fast convergence may overcompensate for a reduction in the linear inner solver efficiency.  ... 
doi:10.1137/08744803 fatcat:6zdiublacfcmbhsjymx3oly65y

Identification of elasto-viscoplastic material parameters by indentation testing and combined finite element modelling and numerical optimization

G. Rauchs, J. Bardon
2011 Finite elements in analysis and design  
between experimental data and results from a finite element model of the indentation test.  ...  Using nanoindentation experiments, the material parameters of an elasto-viscoplastic material model with non-linear isotropic and kinematic hardening are determined by minimizing the least-squares difference  ...  with an associative flow rule, including non-linear isotropic and nonlinear kinematic hardening.  ... 
doi:10.1016/j.finel.2011.01.008 fatcat:n4jpnyne6bcqjnriklh7fu7w74

Page 3714 of Mathematical Reviews Vol. , Issue 81I [page]

1981 Mathematical Reviews  
Feijéo, Analysis of a mathemati- cal model for the motion of a pile thrust into the soil (pp. 125- 134); James H.  ...  From the introduction: “It has been widely known for nearly a century that mean value methods play a fundamental role in associating a sum with an infinite series.  ... 

An anisotropic elastic-viscoplastic damage model for bone tissue

J. J. Schwiedrzik, P. K. Zysset
2012 Biomechanics and Modeling in Mechanobiology  
A new anisotropic elastic-viscoplastic damage constitutive model for bone is proposed using an eccentric elliptical yield criterion and nonlinear isotropic hardening.  ...  Keywords Bone · Constitutive model · Viscoplasticity · Damage An anisotropic elastic-viscoplastic damage model 203  ...  By coupling a phenomenological postyield model to a multiscale homogenization approach predicting elastic properties, an efficient and powerful tool has been proposed to assess the mechanical behavior  ... 
doi:10.1007/s10237-012-0392-9 pmid:22527365 fatcat:c2iufotdwrhsbprvd4ncd4xlja

Simulation of impacts on elastic–viscoplastic solids with the flux-difference splitting finite volume method applied to non-uniform quadrilateral meshes

Thomas Heuzé
2018 Advanced Modeling and Simulation in Engineering Sciences  
Many test cases are proposed and two particular viscoplastic constitutive models are studied, on which comparisons with finite element solutions show a very good accuracy of the finite volume solutions  ...  Elastic-viscoplastic constitutive models falling within the framework of generalized standard materials (Halphen and Nguyen in J Mech 14: 1975) in small strains are considered.  ...  Indeed, for an overstress close to 10 2 MPa, the effective cumulated strain rate has largely increased for that model (see Fig. 21 ), which yields a more important viscoplastic flow.  ... 
doi:10.1186/s40323-018-0101-z fatcat:slgmdkyjvfd3pa6ucbytnb7gxq

Efficient thermo-mechanical model for solidification processes

Seid Koric, Brian G. Thomas
2006 International Journal for Numerical Methods in Engineering  
A new, computationally-efficient algorithm has been implemented to solve for thermal stresses, strains, and displacements in realistic solidification processes which involve highly nonlinear consitutitve  ...  The model is validated both with a semi-analytical solution from Weiner and Boley [2] as well as with an in-house finite element code CON2D [3, 4, 7, 8] specialized in thermo-mechanical modeling of continuous  ...  Even though Nemat-Nasser is an explicit local solution method, it was only slightly faster then the Koric, S. and B.G. Thomas, "Efficient Thermo-Mechanical Model for Solidification Processes", Int.  ... 
doi:10.1002/nme.1614 fatcat:u3oox54ukvhfpg4bcmktgfe6dy

Comparison of models for finite plasticity: A numerical study

Patrizio Neff, Christian Wieners
2003 Computing and Visualization in Science  
The procedure is applied to models with different elastic free energy functionals and a plastic flow rule of von Mises type.  ...  The method is based on a fully implicit discretization in time which results in an iteratively evaluated stress response; the arising nonlinear problem is then solved by a Newton method where the linear  ...  The authors are grateful for the facilities and assistance at the TU Chemnitz for using the Linux cluster CLiC.  ... 
doi:10.1007/s00791-003-0104-1 fatcat:f6vv4hl4orfiza7pfycu3ca7fe

Explicit coupled thermo-mechanical finite element model of steel solidification

Seid Koric, Lance C. Hibbeler, Brian G. Thomas
2009 International Journal for Numerical Methods in Engineering  
The model features an efficient and robust local-global viscoplastic integration scheme to solve the elasticviscoplastic constitutive equations of solidifying steel [1], using a VUMAT subroutine in ABAQUS  ...  Variable mass scaling is used to efficiently model the phenomena in their natural time scale using a Lagrangian formulation.  ...  Casting Consortium at UIUC, the National Science Foundation (Grant CMMI-07-27620), and Corus Steel in IJmuiden, The Netherlands.  ... 
doi:10.1002/nme.2476 fatcat:swxzuh7jqzbmxha2ipmnscbfzu
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