Learning Forum

[jfonken]

Hi all,

As a subproject in my PhD project, I'm comparing Ansys and Abaqus (geometrically) nonlinear solution methods. I used a simple cylinder to represent an artery and modelled it with a simple Neo-Hookean material model. Large deformations (NLGEOM) are turned on (hence the non-linearity). I used 20-nodes hexahedral elements with reduced integration and a mixed UP-formulation.

When I compared the nodal results, I saw that the absolute differences in displacement were very small (10^-10 m). However, the absolute difference in stress goes up to 6*10^4 Pa (below).

[Chandra Sekaran]

Have you tried using ERESX,NO? This will force copying of integration point results to the nodes. nERESX, KeynSpecifies extrapolation of integration point results.nSOLUTION: Analysis OptionsnValid Products: Pro | Premium | Enterprise | PrepPost | Solver | AS add-onntKeynExtrapolation key:nDEFAn ? nIf element is fully elastic (no active plasticity, creep, or swelling nonlinearities), extrapolate the integration point results to the nodes. If any portion of the element is plastic (or other active material nonlinearity), copy the integration point results to the nodes (default).nYESn ? nExtrapolate the linear portion of the integration point results to the nodes and copy the nonlinear portion (for example, plastic strains).nNOn ? nCopy the integration point results to the nodes.n