Interface to Abaqus (3D)

Fill+Pack (with or without Fiber) and Warp results for 3D models can be exported to Abaqus for further structural (usually Stress) analysis.

Note: This feature is only available for 3D models on PC.

An API script (PC only) which automatically converts the necessary result and mesh files into a format that Abaqus can use is available.

The Autodesk Moldflow Insight results are exported in *.xml format and the 3D mesh is exported in Abaqus input (*.inp) format. The API script saves the interface files in a folder created in the current project folder. For example, in Windows XP, My Documents\My AMI 20xx Projects\Project1\<study_name>_interface_files , or in Windows Vista, My Documents\My AMI 20xx Projects\Project1\<study_name>_interface_files ,where xxxx is the version number of the Autodesk Moldflow Insight software you are using and <study_name> is the name of the study you are exporting to Abaqus).

Interfacing to Abaqus

Autodesk Moldflow Insight result and mesh files are binary files. In order to be used in Abaqus, these files need to be converted to ASCII format. Autodesk Moldflow Insight uses an API script, mpi2abq.vbs, to convert these files automatically.

Interface files

There are several types of file that Autodesk Moldflow Insight can export for use in Abaqus. The actual files exported depends on what your Autodesk Moldflow Insight study file contains.

Mesh file

The API script converts the 3D mesh to the Abaqus input format. This interface file is named <study_name>_mesh.inp. For more information about the Abaqus *.inp format, please refer to your Abaqus manual.

Note: Change from Patran to Abaqus input file for the mesh model:

Before the release of MPI 6.0, the Patran (*.pat) file format was used to convert Autodesk Moldflow Insight mesh models for input to Abaqus. Some inconsistencies were found between the mesh model in *.pat format and the result data (*.xml) files produced by the original 3D Abaqus Interface. For example:

  • If there was a short shot predicted, results would not exist on the unfilled elements of the mesh model. Abaqus requires consistency between the mesh model and the corresponding *.xml files.
  • If the mesh model contained mold exterior surface mesh, cooling channels, and/or a runner system, Fill+Pack analysis results would correspond only to elements on the part cavity. Abaqus would fail this model because of the inconsistency between the mesh model and result files.

Further, to interface 3D Overmolding, Microchip Encapsulation, or to interface 3D Warp results using mesh aggregation to Abaqus, the *.pat file format is of limited utility.

Beginning in MPI 6.0, the 3D Abaqus Interface converts the 3D mesh to the Abaqus input format. In this way, Autodesk Moldflow Insight can output the three point constraint for removal of the rigid body movement, build contact surface conditions between multiple components, and pass pressure and temperature conditions directly into the Abaqus input file.

Material properties data files

For fiber-filled materials, these files are produced:

Principal directions
The principal fiber orientation directions are the eigenvectors of the fiber orientation tensor, and the eigenvalues of the fiber orientation tensor representing the probability percentage of fibers aligning in the principal corresponding directions. These data are stored in <study_name>_principalDirections.xml.
Note: Change from fiber orientation tensor to principal directions:

Before the release of MPI 6.0, the fiber orientation tensor passed to the 3D Abaqus Interface, and this data together with the mechanical and thermal expansion coefficient distributions was output by the interface as *.xml files. This caused some inconvenience in data conversion, so beginning in MPI 6.0, Autodesk Moldflow Insight directly outputs the principal directions of the material property set.

Mechanical properties
Are element-based results stored in individual engineering constant component files, such as <study_name>_E11.xml, <study_name>_E22.xml, <study_name>_E33.xml, <study_name>_v12.xml, ..., and these are nine components in principal directions based on the orthotropic assumption. The calculations of these mechanical properties are based on the selected micro-mechanics model and a 9-constant fiber orientation average method along with a selected closure approximation option, which are specified in the Fiber parameters of the Fill+Pack process settings.
Thermal expansion coefficients
Are element-based results stored in <study_name>_ltec_1.xml, <study_name>_ltec_2.xml and <study_name>_ltec_3.xml, representing the linear thermal expansion in the first, second, and third principal directions. These values are calculated based on the selected method in the Fiber parameters of the Fill+Pack process settings, with an orientation average.

For unfilled materials, these files are produced:

  • <study_name>_Moduli.xml
  • <study_name>_PoissonRatios.xml
  • <study_name>_ShearModuli.xml
  • <study_name>_Ltecs.xml
Initial stresses file

Autodesk Moldflow Insight passes the initial stresses calculated by the 3D Warp analysis to the interface. The API script converts this data and stores it in <study_name>_initStresses.xml.

Note: Change from volumetric shrinkage to initial stress data:

Before the release of MPI 6.0, the 3D Abaqus Interface translated the volumetric shrinkage result from 3D Flow, using the strintf3d script, to a format that could be converted into initial stresses by Abaqus' Autodesk® Translator (through a command *INITIAL CONDITIONS, TYPE=STRESS, USER). However, because 3D Warp calculates the initial stresses internally using a proprietary technology, the inconsistency in the final warp results predicted by 3D Warp and by Abaqus could easily be identified. For this reason, beginning in the MPI 6.0 release, the initial stress data calculated by 3D Warp is passed directly to the 3D Abaqus Interface.

Unit conversion

Before the release of MPI 6.0, the interface files were always produced in the SI unit system, and a special script had to be coded to take care of unit conversion. Beginning in the MPI 6.0 release, the mpi2abq script takes care of the unit conversion if you select a unit system other than SI.