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Femap Version 11.4  and Version 11.4.1 have been released.  11.4 is a significant release, with some additional updates and a Nastran point release added in V11.4.1.  If you are under maintenance and haven’t upgraded yet, then you should go straight to 11.4.1 as it is a complete installation.

A complete list is available via Help | What’s New from within Femap, or in  <Femap_install_dir>\pdf\newfeat.pdf .  We recommend reviewing this document, as the items you find most useful may differ from what we think are the best bits, summarised here:

Meshing Toolbox:

• Femap now associates rigid elements (RBE2, RBE3)  with the geometry so that rigid element connectivity is preserved when geometry is re-meshed.  Complex models often involve dozens or hundreds of rigid elements.  For example, we have done rotating mills with 900+ pre-loaded bolts modelled as beam elements connected to solid mesh via RBE2’s at each end attached to the washer areas of the bolted flanges.  The Meshing Toolbox allows local or global changes to mesh sizing where the re-mesh automatically updates the rigid elements.
• This new capability works most effectively when the multiple dependent nodes (RBE2) or multiple independent nodes (RBE3) are all associated with one or multiple pieces of geometry (eg. curves and/or surfaces), and where the id’s of the geometry associated with the RBE nodes are not changed by the editing in the Meshing Toolbox.  Thus the caution is that if a surface of the rigid element is split during an edit (eg. Geometry Editing -> Point-to-Point or Project Curve), then the rigid element will not automatically associate with the newly created surface(s).  However, tests suggest that splitting or combining curves does not upset the auto-association of the updated rigid element – the rigid element will be associated with both curves when one has been split and with the one curve if two have been combined.

Geometry:

• This is probably relevant to earlier versions, but the progression of the Parasolid Geometry Engine means that some new features of geometry editing sneak under the radar without getting any fanfare in the release notes.  For example it is now possible to  Modify | Move By… Points and Curves of solids (including sheet solids) in ways which were impossible previously.  This substantially improves the inevitable process of turning often imperfect CAD geometry (looks good, but isn’t quite right) into excellent FEA geometry – or makes it easier to build any FEA geometry in Femap from scratch.  Just remember that any geometry edits made outside the Meshing Toolbox do not automatically update the mesh.
• Femap can now reverse the normal of surfaces which belong to general sheet solids (Modify | Update Other | Surface Normal).  Previously it was necessary to get your surface normals nice and consistent (if appropriate to the model type, such as a pressure vessel made with plate elements) BEFORE doing the Non-manifold Add to create the multi-surface sheet solid.  It is now possible to update these surface normals after the event.  Note that a general best-practice recommendation is for FEA plate element normals to be consistent where possible to simplify plate stress visualisation and results assessment.  We achieve this by generally having surface normals facing “outwards” on things which can be described as having an “outside” direction, and sort this out in the geometry in advance of meshing.  In the numerous situations where “outside” might be ambiguous, we would make the surface normal topologically consistent with somewhere which does not have the ambiguity – if possible.  For example, a Z shaped stiffener welded on the outside of a vessel would have the “outside” directions of the stiffener topologically consistent and also guided by the flange which is parallel to the vessel.
• Femap now includes Modify | Break | At All Intersections, which allows you to break one (or more) curves at all of the curves’ intersections.  Note that this is one of the numerous geometry editing commands which is outside the Meshing Toolbox, so should not be done on geometry which is already meshed – otherwise you will end up with orphan mesh which is not easy to select.

New Tool Pane: Function/Table Editor:

• The “panes” are the larger Tools such as the Model Info Tree, the Meshing Toolbox and the Postprocessing Toolbox.  The Function/Table Editor pane provides a more helpful interface to creating and using more in-depth tables such as for on-the-fly linear combinations of base results sets.  It is also easier to create things like temperature dependent stress-strain curves -ie. Function vs Temperature.  In the older method it was necessary to know the ID of each function which defined the stress-strain curve at different temperatures, while the new pane allows the stress-strain functions to be chosen from a drop-down list and simply linked to the relevant temperature value in the table.

Loads:

• Model | Load | Map Output from Model has been enhanced. This command is used to create loads in one model from results in another, even if the mesh is different.  The improvement is to allow more “Data Conversion” options for the way in which the results are used.  This follows the same philosophy as for viewing results – ie. whether values are averaged results, maximum results, minimum results and whether or not the element corner (element nodal) results or element centroidal results are used when calculating the loads to be created.

Miscellaneous

Other miscellaneous niceties include:

• Addition of Tools | Vector Manager and Tools | Plane Manager – these allow regularly used vectors or planes to be saved as named entities.  Whenever an operation needs a vector or a plane the Methods button now includes the “Saved” option to select a stored Vector or Plane.
• The Charting Pane now allows results to be transformed on-the-fly when creating Data Series – including transform of both results for Vector vs Vector Data Series.
• Nastran updates are mostly esoteric error fixes – we recommend reviewing the Release Guide in <Femap_install_dir>\nastranhelp\pdf.

If you have any questions about V11.4.x, please give us a call.