Importing Nastran Features

You can import multiple types of Nastran files into the 3DEXPERIENCE platform. The import function transforms your simulation data from the Nastran card format to the Abaqus keyword format.

After the import completes, an appropriate simulation app opens. For example, if you imported model data, the Structural Model Creation app opens; if you imported scenario data, a scenario creation app opens.

You can view the full data for features that you import and make limited edits, depending on how you perform the import. If you import the features based on bulk data, you can make limited edits in the 3DEXPERIENCE platform; if you import the features based on specifications, you can edit all imported features except mesh parts and groups.

This task shows you how to:

Import Nastran Features Based on Bulk Data
Import Nastran Features Based on Specifications
View and Edit Imported Nastran Features

Before you begin: You must have the appropriate role to import Nastran features.

Import Nastran Features Based on Bulk Data

You can import features based on bulk data to reduce and optimize the size of the model. This method is well suited for scenarios in which you need to import a large legacy model.

Only use this method if you plan to modify only a few parameters after the import.

From the top bar, click Add > Import.

Expand the Required section, and do the following:

From the Format options, select one of the following Nastran formats:
- Nastran files (*.bdf)
- Nastran files (*.dat)
- Nastran files (*.nas)

From the Source options, select one of the following:


Option	Description
File on disk	The file exists on your computer or in a network location.
Exchange space	The file exists in an exchange space.
Collaborative space	The file exists in the 3DEXPERIENCE database.

Select the file from the appropriate source.

Expand the Options section, and click the General tab.
Optional: Select Preview imported data to open the preview window.
Once you click OK in the Import dialog box, the preview window appears. This window lets you see the imported files, browse the file structure, and manage the import options.
Select Always create a new product to insert the newly created FEM representation into a new product.
Creating a FEM representation (without a current product) creates a new product.
Select Merge equivalent data to import only one data card if equivalent data is present in multiple data cards.
This behavior is applicable only for MAT1, MAT2, MAT8, MAT9, CONROD, and CONM2 data cards.
From the Generated features options, select Bulk data to generate features based on the bulk data.

From the Data to import options, select one of the following:

Option	Description
All	Imports scenario, mesh, and model data.
Model only	Imports mesh and model data.
Mesh only	Imports mesh data only.

Select Structure all features by files to create different features for each instance of the same type of Nastran card found in different imported files.
Select Structure FEM by files to consider all files with nonconnection mesh data as candidates for FEM representation creation within a FEM assembly.
When you select this option, the 3DEXPERIENCE platform:
- Imports each FEM representation as an independent self-sufficient component. Each FEM representation includes all of its corresponding materials, axis systems, properties, connections, and mass definitions of the mesh contents.
- Creates connections and display elements, which are defined by the mesh contents of two different FEM representations, in the FEM assembly.
- Imports matrix data into the FEM assembly.
- Links scenario data to the FEM assembly.
Select Structure mesh parts and properties by PID to create mesh parts and properties per property identification (PID) number.
Click OK.
A progress bar appears and displays the status of the import.
After the import completes, the progress bar closes and the Import Report window appears.
The import report provides diagnostics that include the status of the import, log information, and information about any unsupported Nastran cards present in the imported Nastran file that failed to import. This information includes Nastran cards with an invalid definition in the input file.
Close the Import Report window.

The imported features appear in the tree. You can click them to view their details.

Import Nastran Features Based on Specifications

You can import features based on specifications, which provides you more flexibility than importing features based on bulk data with regard to editing features. This method is well suited for scenarios in which you need to edit a large number of features.

The resulting model might be large depending on the number of connection entities in the imported file.

From the top bar, click Add > Import.

Expand the Required section, and do the following:

From the Format options, select one of the following Nastran formats:
- Nastran files (*.bdf)
- Nastran files (*.dat)
- Nastran files (*.nas)

From the Source options, select one of the following:


Option	Description
File on disk	The file exists on your computer or in a network location.
Exchange space	The file exists in an exchange space.
Collaborative space	The file exists in the 3DEXPERIENCE database.

Select the file from the appropriate source.

Expand the Options section, and click the General tab.
Optional: Select Preview imported data to open the preview window.
Once you click OK in the Import dialog box, the preview window appears. This window lets you see the imported files, browse the file structure, and manage the import options.
Select Always create a new product to insert the newly created FEM representation into a new product.
Creating a FEM representation (without a current product) creates a new product.
From the Generated features options, select Specification-based to generate features based on their specifications.
When you import features based on their specifications, the 3DEXPERIENCE platformimports only the model data.
Select Skip duplicate materials to prevent the import of materials from the Nastran file if those materials already exist in the database.

From the Structure mesh parts by options, select one of the following:

Option	Description
Dimensions	Generates a mesh part per mesh dimension. For example, if you import a file that has mesh data for three dimensions, the 3DEXPERIENCE platform generates three mesh parts.
Sections	Generates a mesh part per property.

Select Connection properties to import all connector-related objects (if present in the original model) with the FEM.
These objects include:
- Connectors, couplings, springs, and dashpots, along with their properties (for example, elasticity, damping, reference length, etc.)
- Tie connections, along with their properties (for example, tie rotational degrees of freedom, constraint ratios, position tolerances, etc.)
Click OK.
A progress bar appears and displays the status of the import.
After the import completes, the progress bar closes and the Import Report window appears.
The import report provides diagnostics that include the status of the import, log information, and information about any unsupported Nastran cards present in the imported Nastran file that failed to import. This information includes Nastran cards with an invalid definition in the input file.
Close the Import Report window.

The imported features appear in the tree. You can click them to view their details.

View and Edit Imported Nastran Features

You can view and edit the data of a limited set of imported Nastran features.

From the tree, double-click a 3DEXPERIENCE feature corresponding to your import.
A dialog box appears, displaying the feature's primary data. You can edit limited types of primary data from this dialog box.
Optional: Edit the feature's primary data in the table.
To view or edit additional data about the feature, do the following:
1. Double-click a row in the table.
  
  Tip: You can also right-click the row and select Edit from the context menu.
  
  A second dialog box appears, displaying additional data related to the row that you selected.
2. If applicable, expand the Data and Advanced sections.
  The labels convey the Abaqus content.
3. Optional: Edit the feature's data.
  Any modifications to the feature's primary data synchronize with the data displayed in this dialog box, and vice versa.
4. Click OK.
Click OK.