Total and Updated Lagrangian formulations are generally available for both the implicit and nonlinear explicit dynamic analysis.
But when is which applied? Does Abaqus mix them?
Hi,
both TL snd UL approaches play a role in large deformation analysis only (there is no difference between them for small deformations and small strains). I don't really know the procedure used in Abaqus, but several FE codes prefer a TL approach for hyperelasticity resp. if the constitutive equations are functions of the deformation history as a whole. UL approach is used e.g. for rate constitutive equations, including the case of hypoelasto-plasticity where the "elastic" part is not derived from a potential (also referred to as the "ad hoc" extension of small strain elasto-plasticity to large deformations). Hope this helps.
Regards
Ansys uses TL for hyperelasticity. If you have dissipative effects (more generally where the constitutive model requires history dependent variables), as in plasticity, creep etc UL is normally used.
Thanks
Sincerely
-Sidd
ABAQUS uses updated Lagrangian formulation as Bazant stated in a recent publication.
Hi guys, sorry for my late response ... and eventually heating-up again that (many decades old) discussion:
Have you ever tried to re-compute the BAZANT results for simple shear example (in plane strain, neoHooke hyperelasticity)?
I am not able to obain the "well known" (?) oscillating shear stress results ... ;-(
Greetings !
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