Background

In ProTOp the FEA model used in all optimization processes is fully preprocessed in order to make the optimization processes fast and efficient. This preprocessed FEA model can be exported in order to be used by some third-party FEA software. Note, however, that during model preprocessing some model information is lost and can not be recovered any more. For example, a surface traction is replaced by the corresponding nodal forces; so, the surface traction object does not exist any more and can not be recovered.

Currently, only the

• Abaqus INP format

NOTE. During FEA model preprocessing some model information is lost and can not be recovered any more. For example, a surface traction is replaced by the corresponding nodal forces.

█ Export limitations

ProTOp's FEA model contains many special optimization-related features. Besides of this, the internally engaged FEA model is heavily preprocessed. For these reasons, there are quite some limitations for the FEA model to be exported. Below is a list of features that are not supported by the exporter.

• Rigid bar elements. Any such elements will be ignored at export and the exporter will issue a warning message.
• Prestrained material. Any material prestraining will be ignored at export and the exporter will issue a warning message.
• Skew supports Any skew supports (displacements prescribed along inclined coordinate axes) will cause the exporter to terminate with an error message.

Apart from these hard limitations there are also a few soft limitations that do not produce any error or warning messages, but should be kept in mind in order to understand what is actually exported. These soft limitations are related to semi-contact and semi-plastic materials, as follows.

• Semi-contact material. This special ProTOp feature is exported in a way that approximates a contact situation. This approximation is of limited accuracy and is suitable only for the corresponding exported supports and loads. In other words, the boundary conditions of the exported FEA model must not be changed.
• Semi-plastic material. This special ProTOp feature is exported as a bilinear elastic-plastic material. This means that ProTOp's FEA response will be only some approximation of the response computed from the exported FEA model.

At export ProTOp generates one complete export model file for each unsuppressed load case.

█ How to ...

Export only selected material regions

To export a FEA model with only some of the material regions included, do the following:

• Open the Session manager and create a copy of the active session. This step is not obligatory; it is just recommended to preserve the original session unchanged.
• Open the Regions removal tool from the FEA Model tab and remove the material regions that should not be exported.
• Open the Model export tool and export the current model.

Export only selected load cases

To export a FEA model with only some of the load cases included, do the following:

• Open the Session manager and create a copy of the active session. This step is not obligatory; it is just recommended to preserve the original session unchanged.
• Open the Load cases dialog from the FEA Model tab and suppress the load cases that should not be exported.
• Open the Model export tool and export the current model.