About Composites Link Export Plies

Key Attributes of Plies

Geometry

Underlying surface and one or more closed contours that lie on the underlying surface.

Draping Direction

By default, the draping direction (or stacking direction) is the normal of the underlying surface. It can be inverted as required.

Note: Individual plies in a plies group may have different draping directions but this practice is confusing and not recommended. Best is to keep the draping directions consistent.

Material

The ply material contains composites-specific physical attributes (such as thickness and maximum shear) as well as mechanical properties.

Rosette

The Rosette defines the reference frame for specifying the warp (and weft if appropriate) directions of the ply. It is best if all plies in a Plies Group reference the same rosette.

Note: The Z-direction of the Rosette can be defined in an opposite direction to the draping direction, but this practice is confusing and not recommended.

Direction

This is the nominal angular direction with respect to the rosette and is one of the discrete values defined in the Composites Parameters.

Seed Point

The seed point is part of the producibility parameters, and not always present.

Stacking

Plies are used once in the stacking, which represents a chronological sequence of application onto the model. However, in the analysis world, plies can be used more than once in a Layup for a more efficient use of data. The draping direction of a ply can be modified at this point when assigning an analysis ply to a Layup.

Mesh Options

You can select the elements on which the ply data are exported. These elements can be created by:

Tessellation

The underlying surfaces of the plies are cut up using every ply boundary and curves referenced by the producibility parameters (such as guide curves and order of drape regions), and then tessellated to create triangular shell elements on which the ply layup is defined. This representation reflects the 3DEXPERIENCE representation accurately, but is not suitable for Finite Element Analysis (FEA). In this case, the layup file generated by Composites Link needs be mapped onto a layup model based on an analysis mesh in the analysis environment. This can be undertaken by all analysis products using Simulayt's Layup technology, such as the Composites Modeler for Abaqus/CAE, as well as a few third-party analysis tools.

Mesh selection

Not available if no shell elements exist in the model.

You need to open the mesh rather than the part. The mesh has a link with the part (visible in the tree). Composites Link tools are available. You can then select the mesh from the tree.

External Mesh file

A shell mesh is read from a selected Nastran bulk data file (.bdf or .dat), an Abaqus .inp file (the first part only) or Layup file and displayed in the viewport to make sure it corresponds to the geometry. Composites Link first maps the ply layup onto this mesh using 3DEXPERIENCE core sampling capability before exporting a Layup, Composites HDF5 or FEA input file containing the ply layup This exported file can be imported directly into the analysis environments and used without further mapping.

Fiber Angles Options

The export of plies involves calculating the fiber angles and writing the data to the export file.

When using surface tessellation, the facets of the tessellation are treated as elements for the export.

When Surface Tessellation is selected:

• For Regenerated (Actual), Composites Link runs the draping simulation to calculate the angle on each element if producibility parameters are defined.
  • If the simulation is successful, the data are written to the file:
    • For Layup, the ply definition is written for the layup file that other Simulayt tools can use later to repeat the draping algorithm to determine fiber angles at every element.
    • For other output files, the data is written explicitly as a fiber angle for each element (exact format depends on the export file type).
  • If the simulation fails, the ply is processed using Regenerated (Theoretical).
• For Regenerated (Theoretical), Composites Link computes angles based on the projection of the reference direction onto each element, rotated by the ply angle. This data is always written explicitly to files as an angle per element.

When Mesh Selection or External Mesh file are selected, 3DEXPERIENCE uses core samplings to determine which mesh elements are in each ply (Ply coverage).

• Core Sample (Theoretical) transfers the Rosette to retrieve the theoretical projected fiber angle on each element.
• Core Sample (Actual) runs the producibility solver method specified for the ply to determine the fiber angle per element.

In both cases, the angles per element are written explicitly.

• For Regenerated (Theoretical) and Regenerated (Actual), Composites Link uses the ply coverage and the ply definition to simulate the draping and compute fiber angles, as for a surface tessellation.

The Core Sample option is strongly recommended wherever possible as this option always reflects the correct results of present and future fiber simulations, yet has good performance even for large numbers of elements.

The core sampler finds all surfaces of the model aligned with the centroid of each element in the mesh and includes the plies defined on the detected surfaces onto the elements. Set Core Sample Range to a value sufficient to pick up any nearby surfaces that have the intended target plies. Or reduce the Core Sample Range to prevent the inclusion of plies from unwanted surfaces.

Only surfaces with a local normal within the Angle Tolerance are included. Angle Tolerance prevents the unintended inclusion of plies from faces on the other side of a corner on the surface.

Export of Points

When exporting plies from a part to a Layup file, you can include Points to be used for Stress Recovery or reference points for down stream applications. The points to export must be visible points (not hidden) in a Geometrical Set Target Points under the root level. These are added to the point store at the root level of the Layup object.