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This option can be defined in the Abaqus environment file as follows:

```txt
adams_unit_family=unit-family 
```

# length

This option specifies the length units for the model. If this option is specified, it overrides the length units of the specified units system.

This option can be defined in the Abaqus environment file as follows:

```txt
adams_length_units=length-unit 
```

# mass

This option specifies the mass units for the model. If this option is specified, it overrides the mass units of the specified units system.

This option can be defined in the Abaqus environment file as follows:

```python
adams_mass_units=mass-unit 
```

# time

This option specifies the time units for the model. If this option is specified, it overrides the time units of the specified units system.

This option can be defined in the Abaqus environment file as follows:

```python
adams_time_units=time-unit 
```

# force

This option specifies the force units for the model. If this option is specified, it overrides the force units of the specified units system.

This option can be defined in the Abaqus environment file as follows:

```txt
adams_force_units=force-unit 
```

# mnf\_elset

This option defines a set of elements whose facets will be exported to the modal neutral file and, therefore, will be available for viewing in MSC.ADAMS. This option does not affect the mechanics of the solution.

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# 3.2.39 TRANSLATING AN Abaqus SUBSTRUCTURE TO A SIMPACK FLEXIBLE BODY

Product: Abaqus/Standard

# Reference

• “Execution procedure for Abaqus: overview,” Section 3.1.1

# Overview

The abaqus tosimpack translator converts an Abaqus substructure to a flexible body in a format that can be used by the SIMPACK multibody dynamics code.

The translator reads Abaqus data from a substructure SIM file and writes data to a SIMPACK flexible body interface (.fbi) file.

# Using the translator

The following procedure summarizes the typical usage of the abaqus tosimpack translator:

1. Create an Abaqus substructure. (General guidelines for building Abaqus models with substructures are described in “Using substructures,” Section 10.1.1.)

The substructure generation step must include the following options:

```c
*SUBSTRUCTURE GENERATE, MASS MATRIX=YES, RECOVERY MATRIX=YES
*FLEXIBLE BODY, TYPE=SIMPACK 
```

2. Run the Abaqus analysis.   
3. Run the abaqus tosimpack translator to read the substructure SIM database produced by the analysis and to create the flexible body interface file.

# Command summary

abaqus tosimpack

```ini
job=job-name
[substructure_sim=filename]
[units=mmks | mks | cgs | ips]
[length=length-units-name]
[mass=mass-units-name]
[time=time-units-name]
[fbi_elset=elset-name] 
```

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# Command line options

# job

This option specifies the input and output file names to use during results translation. The job-name value is used to construct the default substructure SIM database file name, job-name.sim. The output flexible body interface file is given the name job-name.fbi.

If this option is omitted from the command line, you will be prompted for this value.

# substructure\_sim

This option specifies the name of the substructure SIM database (.sim) file if it is different from jobname.sim. The file will usually be named job-name\_Znn.sim.

# units

This option specifies the units system for the Abaqus model. The possible values are mmks (millimeters-kilograms-seconds), mks (meters-kilograms-seconds), cgs (centimeters-grams-seconds), and ips (inches-pounds-seconds). The default value is mks.

# length

This option specifies the length units for the model. The valid options are meters, m, millimeters, mm, centimeters, cm, kilometers, km, inches, inch, in, feet, foot, ft, and mile. If this option is specified, it overrides the length units of the specified units system.

# mass

This option specifies the mass units for the model. The valid options are kilograms, kg, megagram, tonne, gram, g, pound\_mass, lbm, pound, slug, kpound\_mass, and ounce\_mass. If this option is specified, it overrides the mass units of the specified units system.

# time

This option specifies the time units for the model. The valid options are seconds, sec, milliseconds, ms, minutes, min, and hours. If this option is specified, it overrides the time units of the specified units system.

# fbi\_elset

This option defines a set of elements whose facets will be exported to the flexible body interface file and, therefore, will be available for viewing in SIMPACK. This option does not affect the mechanics of the solution.

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# 3.2.40 TRANSLATING AN Abaqus SUBSTRUCTURE TO AN EXCITE FLEXIBLE BODY

Product: Abaqus/Standard

# Reference

• “Execution procedure for Abaqus: overview,” Section 3.1.1

# Overview

The abaqus toexcite translator converts an Abaqus substructure to a flexible body in a format that can be used by the EXCITE multibody dynamics code.

The translator reads Abaqus data from a substructure SIM file and writes data to an EXCITE flexible body interface (.exb) file.

# Using the translator

The following procedure summarizes the typical usage of the abaqus toexcite translator:

1. Create an Abaqus substructure. (General guidelines for building Abaqus models with substructures are described in “Using substructures,” Section 10.1.1.)

The substructure generation step must write at least mass and stiffness matrices, and it must include the \*FLEXIBLE BODY option as follows:

```txt
*SUBSTRUCTURE GENERATE, MASS MATRIX=YES
*FLEXIBLE BODY, TYPE=EXCITE or GENERIC 
```

• If TYPE=EXCITE, an EXCITE flexible body of type SMOT, including high-order inertia invariants, is created.   
• If TYPE=GENERIC, an EXCITE flexible body of type CON6 is created.

2. Run the Abaqus analysis.

3. Run the abaqus toexcite translator to read the substructure SIM database produced by the analysis and to create the flexible body interface file.

# Command summary

abaqus toexcite

```txt
job=job-name
[substructure_sim=filename] 
```

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# Command line options

# job

This option specifies the input and output file names to use during results translation. The job-name value is used to construct the default substructure SIM database file name, job-name.sim. The output flexible body interface file is given the name job-name.exb.

If this option is omitted from the command line, you will be prompted for this value.

# substructure\_sim

This option specifies the name of the substructure SIM database (.sim) file if it is different from jobname.sim. The file will usually be named job-name\_Znn.sim.

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# 3.2.41 TRANSLATING MOLDFLOW DATA TO Abaqus INPUT FILES

Product: Abaqus/Standard

# References

• “Execution procedure for Abaqus: overview,” Section 3.1.1   
• “Moldflow translation examples,” Section 1.3.19 of the Abaqus Example Problems Guide

# Overview

Moldflow Plastics Insight (referred to as Moldflow in this section) from Autodesk, Inc. models the plastics injection mold-filling process. The results of a Moldflow simulation include calculations of material properties and residual stresses in the plastic part.

The abaqus moldflow translator transforms finite element model information from a Moldflow analysis into a partial Abaqus input file. The translator requires the Moldflow interface files that are created by the Moldflow analysis. (See “The Moldflow interface files” for more information.)

For midplane simulations the abaqus moldflow translator reads the interface (.pat and .osp) files created by abaqus moldflow translator Version MPI 3 or later.

For three-dimensional solid simulations using Moldflow Version MPI 6 the translator reads the interface (.inp and .xml) files created using the Visual Basic script mpi2abq.vbs. This script is part of an Abaqus installation and is typically found in the moldflow\_install\_dir/Plastic Insight 6.0/data/commands directory.

# Using the translator

The following procedure summarizes the typical usage of the abaqus moldflow translator:

1. Run a Moldflow simulation.   
2. Export the data as follows:   
• For a midplane Moldflow simulation export the finite element mesh data to a file named job-name.pat and the results data (material properties and residual stresses) to a file named job-name.osp.   
• For a three-dimensional solid Moldflow simulation using Moldflow Version MPI 6 run the Visual Basic script mpi2abq.vbs to export the finite element mesh data to a file named job-name\_mesh.inp and the results data to .xml files.   
3. Run the abaqus moldflow translator to create a partial Abaqus input file from the Moldflow interface files.   
4. Edit the Abaqus input file to add appropriate data for the analysis (for example, add boundary conditions and step data).   
5. Submit the Abaqus input file for analysis.

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The Moldflow interface files contain finite element mesh data, material property data, and residual stress data.

For midplane simulations you must use Moldflow to create two interface files: job-name.pat and job-name.osp. Both files must use the same units.

For three-dimensional solid simulations using Moldflow Version MPI 6, the mesh and results files for filled and unfilled models are listed in Table 3.2.41–1.

Table 3.2.41–1 Interface files generated using the Visual Basic script for Moldflow Version MPI 6. 

<table><tr><td>Data type</td><td>Filled model</td><td>Unfilled model</td></tr><tr><td>Finite element mesh data</td><td>job-name_mesh.inp</td><td>job-name_mesh.inp</td></tr><tr><td rowspan="14">Results data</td><td>job-name_v12.xml</td><td rowspan="3">job-name_PoissonRatios.xml</td></tr><tr><td>job-name_v13.xml</td></tr><tr><td>job-name_v23.xml</td></tr><tr><td>job-name_g12.xml</td><td rowspan="3">job-name_ShearModuli.xml</td></tr><tr><td>job-name_g13.xml</td></tr><tr><td>job-name_g23.xml</td></tr><tr><td>job-name_ltec_1.xml</td><td rowspan="3">job-name_Ltecs.xml</td></tr><tr><td>job-name_ltec_2.xml</td></tr><tr><td>job-name_ltec_3.xml</td></tr><tr><td>job-name_e11.xml</td><td rowspan="3">job-name_Moduli.xml</td></tr><tr><td>job-name_e22.xml</td></tr><tr><td>job-name_e33.xml</td></tr><tr><td>job-name_initStresses.xml</td><td>job-name_initStresses.xml</td></tr><tr><td>job-name_principalDirections.xml</td><td></td></tr></table>

# Finite element mesh data

The Moldflow interface files contain finite element mesh data.

• For midplane simulations the mesh data are in a Patran neutral file containing nodal coordinates, element topology, and element properties.   
• For three-dimensional solid simulations the mesh data are in an Abaqus input file containing nodal coordinates, element topology, element properties, and boundary conditions sufficient to eliminate

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the structure’s rigid body modes. Solid elements in the mesh files are always 4-node tetrahedra. The translator has an option to convert these to 10-node tetrahedra.

# Material property data

The Moldflow interface material property data file contains elastic and thermal expansion coefficients for each element. For midplane simulations these properties may be isotropic or orthotropic. For threedimensional solid simulations of filled models these properties are orthotropic. For three-dimensional solid simulations of unfilled models the data files contain orthotropic data adjusted to represent physically isotropic materials.

# Residual stress data

The abaqus moldflow translator calculates residual stresses in the plastic part after it has cooled in the mold. These residual stresses can be translated to initial stresses for the Abaqus structural analysis.

• For midplane simulations a plane stress initial stress state is defined in the same directions as the material properties. The stress state in the material coordinates is defined in terms of the principal stresses (the shear stress is zero).   
• For three-dimensional solid simulations residual stresses for each element in job-name\_initStresses.xml are in global coordinates. The translator transforms these coordinates to the same directions as the material properties.

# Assumptions used to translate the Moldflow data for midplane simulations

For midplane simulations the abaqus moldflow translator makes a number of assumptions regarding the topology and properties of the data. These assumptions, listed below, ensure compatibility with the options available in the current release of Abaqus.

• The Moldflow mesh can consist of 3-node, planar, triangular elements as well as 2-node, onedimensional elements that represent components such as runners and ribs. The abaqus moldflow translator converts the triangular elements to an identical mesh of Abaqus S3R shell elements. One-dimensional elements in the Moldflow mesh are not translated.   
• The number of layers in the Abaqus S3R shell elements created by the abaqus moldflow translator is equal to the number of layers passed by Moldflow, which is 20. As a result, the mechanical properties and stress data passed to the translator apply to 20 layers through the thickness.   
• The Abaqus input data created by the abaqus moldflow translator depend on the kind of material defined in the interface (.osp) file as follows:

For unfilled isotropic materials Abaqus assumes the following:

– A homogeneous shell formulation.   
– Isotropic material constants.   
– Abaqus section point initial stresses are interpolated from the values at the Moldflow through-thickness integration points.

For unfilled transversely isotropic materials Abaqus assumes the following:

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– A homogeneous shell formulation.   
– Transversely isotropic material constants defined for the section in terms of material principal directions plus the orientation with respect to the local Abaqus coordinate system.   
– Abaqus section point initial stresses are interpolated from the values at the Moldflow through-thickness integration points.

For fiber-filled materials Abaqus assumes the following:

– A composite shell formulation.   
– Lamina material constants defined for each layer in terms of material principal directions plus the orientation with respect to the local Abaqus coordinate system for each layer.   
– Moldflow through-thickness integration points are taken as the midpoint of each Abaqus layer.   
– Material properties are constant for each layer.   
– Abaqus section point initial stresses are the same as the values at the Moldflow throughthickness integration points and constant through each layer.

The Abaqus input file that the abaqus moldflow translator generates does not contain boundary condition and load data. You must add this information to the input file manually.

# Assumptions used to translate the Moldflow data for three-dimensional solid simulations

For three-dimensional solid simulations the abaqus moldflow translator makes a number of assumptions regarding the topology and properties of the data. These assumptions, listed below, ensure compatibility with the options available in the current release of Abaqus.

• The abaqus moldflow translator converts the tetrahedral elements to an identical mesh of Abaqus C3D4 or C3D10 solid elements (for more information, see the command line options below).

• Orthotropic material constants are in terms of material principal directions.

• Material properties are constant for each element.

• Orientations are defined in job-name\_principalDirections.xml by giving vectors defining the local 1- and 2-directions.

• Residual stresses computed by the WARP3D module of Moldflow in jobname\_initStresses.xml are transformed from global coordinates to local material directions and used as initial stresses in Abaqus.

• Loads and boundary conditions representing service loads must be added to the input file manually. For simulations using Moldflow Version MPI 6, the Abaqus input file created by the translator contains boundary conditions sufficient to remove rigid body modes from the model so that an analysis can easily solve for the response due to initial stresses.
