This example NLAD-ETCHG analysis features a plate with notches meshed with SOLID185 elements undergoing small deformation (NLGEOM,OFF).

Figure 4.5: Initial Model Showing Details at the Location of the Notches

The model uses a linear elastic material:

Pressure loads are applied.

NLADAPTIVE and other commands are shown in the following figures. For more information, see Understanding the NLAD-ETCHG Process.)

Figure 4.6: Specifying the Desired Element Type (ET,101,187) for NLAD-ETCHG

Figure 4.7: Specifying Remeshing Criterion (Energy) for NLAD-ETCHG

The first remeshing converts the hexahedral SOLID185 mesh to tetrahedral SOLID187. Subsequent remeshings refine the tetrahedral SOLID187 mesh via an energy-based criterion (as specified via NLADAPTIVE).

Figure 4.8: Remeshing History

The following figure shows the equivalent stress plots corresponding to the substeps just prior to the hex-to-tet conversion (2), immediately after hex-to-tet conversion (3), and the last substep (5) (following two standard nonlinear mesh adaptivity remeshings using the specified criterion for refinement).

Figure 4.9: Equivalent Stress at Substeps 2, 3, and 5

This example NLAD-ETCHG analysis features an offset punch of a block meshed with SOLID186 elements undergoing large (NLGEOM,ON).

The model is a deformable elastoplastic block with a rigid indenter punch through which vertical displacement loads are applied.

Figure 4.10: Initial Model of Offset Punch

The material type is elastoplastic (TB,PLASTIC,,,,BISO):

Loading occurs via an applied displacement through the pilot node on a rigid target.

NLADAPTIVE and other commands are shown in the following figures. For more information, see Understanding the NLAD-ETCHG Process.)

Figure 4.11: Specifying the Desired Element Type (ET,101,187) for NLAD-ETCHG

Figure 4.12: Specifying Remeshing Criteria (Energy and Skewness) for NLAD-ETCHG

The first remeshing converts the hexahedral SOLID185 mesh to tetrahedral SOLID187. Subsequent remeshings refine the tetrahedral SOLID187 mesh via the energy-based and skewness criteria (as specified via NLADAPTIVE).

Figure 4.13: Remeshing History

The following figure shows equivalent plastic strain plots corresponding to the substeps just prior to NLAD-ETYPE (9), immediately following NLAD-ETYPE (10), and at the last substep (28) (following three conventional nonlinear mesh adaptivity remeshings using the specified criteria for refinement).

Figure 4.14: Equivalent Plastic Strain at Substeps 9, 10, and 28