The 3D Mesh to Geometry Plug-in allows Abaqus FEA users to generate geometry from mesh files. This plug-in converts .STL files and meshes back to geometry in order to remesh the structure, as well as importing into a variety of CAD packages.
Available downloads for the 3D Mesh to Geometry Plug-in:
With the 3D Mesh to Geometry Plug-in, users can create a geometry representation of an orphan mesh within Abaqus/CAE. The geometry-file will be written in ACIS-format (.SAT) and essentially consists of triangular faces corresponding to the outer faces of the original mesh. If required, the geometry repair options and/or virtual topology allow the user to clean the geometry.
This 3D Mesh to Geometry Plug-in is part of an advanced and generic remesh capability. This remesh tool allows users can run simulations (2D and 3D, Standard and Explicit) in which remeshing/rezoning should take place because of element distortion.
This extension was developed by the SIMULIA Benelux office and can be ordered directly from them. Contact SIMULIA Benelux
The Abaqus Welding Interface (AWI) streamlines the generation of two-dimensional welding simulations from within Abaqus/CAE. This application provides a model-tree based approach to defining all aspects of the weld model such as weld beads, weld passes, film loads, radiation loads and more. Downloadable files are made available for the Weld Modeler below. The link below is to the latest version which includes 3D weld modeling capabilities.
The Abaqus Welding Interface is licensed annually by a services contract through the SIMULIA South office in Lewisville, TX, USA. Please contact Beverly Andrews for licensing questions. Please contact Murali Pandheeradhi of the SIMULIA Erie office for technical questions.
A license key based on the Abaqus site ID will be generated by the SIMULIA South office which will allow the AWI to be run by any number of users at one time. There is no paid-up license option for the AWI. Please contact our office through the link at the bottom of this page for more details.
In order to install the Abaqus Welding Interface plug-in, click on the link above and save the file to a temporary directory. Then unzip the saved file and copy the resulting folder into the abaqus_plugins folder of your Abaqus installation.
Two MOV video files are available for download. The demos cover all the steps required to generate 2D and 3D weld models. The demos each last 30-40 minutes.
Within the Abaqus FEA product suite from SIMULIA, the user subroutine RSURFU can create a torus-shaped rigid surface. This torus surface has user definable radii so that it can model radial expansion, contraction, bending, and pulsatile motion of deformable tube-like structures (such as stents and tube-in-tube applications). The Adjustable Rigid Torus (ART) is an Abaqus extension that provides a graphical user interface (GUI) in Abaqus/CAE to supply the necessary parameters used by the subroutine, RSURFU. In addition, the ART also provides an option to construct a surface part to visualize the user-defined torus surface.
ART is unique to Abaqus in that it contains the following features that facilitate stent or tube-in-tube analyses
A single application to drive both torus and cylindrical shaped surfaces in Abaqus/Standard.
Automatic detection and snap to the deformable mating surface radius.
Ability to define the rigid surface through either a graphical user interface in Abaqus/CAE or through a text file used directly with the Abaqus input file.
Ability to visualize the rigid surface throughout the analysis when used in conjunction with Abaqus/CAE.
Ability to use the visualization surface to drive a subsequent Abaqus/Explicit submodel. (In this case, the Abaqus/Standard model would be run first to define the motion of the visualization surface.)
As shown below, users can input the radius values in the table for each step. The auto-detect feature of the ART can intelligently adjust the beginning radius to match the radius of the simulating part. The contact between the RSURFU and the model part can be automatically established through the ART GUI. The built-in custom data checking ensures successful execution of the extension.
Expansion-Relaxation-Crimping of a Stent
In this example, the ART was used to:
Define contact between the balloon and inner stent surface and to expand the stent
Define contact between the catheter and outer stent surface and to crimp the stent
The auto-detect feature of the ART automatically snapped the rigid surface to the deformed stent radius without having to restart the analysis.
Bending and Pulsation of a Stent
This example uses the ART to accomplish simultaneous bending and pulsation of a stent. Visualization of the rigid surface with the stent under different loading modes was not possible before.
The ART can be used to effectively model tube-in-tube applications. Simultaneous expansion, contraction, and bending of the tubes can be easily modeled and visualized.
The Bolt Studio plug-in provides the user with a streamlined method for defining bolts, nuts, and washers, and placing them into an existing Abaqus/CAE model. Users can control the default set of bolts that are displayed in the interface via a simple Python-based configuration file. The bolts, nuts, and washers, where applicable, are generated parametrically within Abaqus/CAE, and meshed automatically using a hexahedral mesh. The mesh size is determined automatically based on the dimensions of the bolt (the user can re-mesh, if required, the parts using the native meshing tools within Abaqus/CAE). The bolt is automatically partitioned and the user specified pre-loading applied.
GM BoltStudio: A Suite of Extensions to Abaqus/CAE for Simulating Bolted Assemblies at General Motors, SIMULIA Community Conference 2009 Download Paper
Filament winding has become a popular construction technique in a wide variety of industries for creating composite structures with high stiffness-to-weight ratios. The difficulty in accurately analyzing the structural behavior of a filament wound body derives from the continually varying orientation of the filaments. The standard capabilities of commercial finite element codes are inadequate to model the spatial variation of fiber orientation in a practical way.
This extension plugs into Abaqus/CAE and enables users to create, run, and postprocess a finite element model, allowing for detailed specification of structural geometry and winding layout parameters. Downloadable files are made available for the Wound Composite Modeler below.
The Wound Composite Modeler is licensed annually by a services contract through the SIMULIA South office in Lewisville, TX, USA.
A license key based on the Abaqus site ID will be generated by the SIMULIA South office which will allow the WCM to be run by any number of users at one time. There is no paid-up license option for the WCM. Please contact our office through the link at the bottom of this page for more details.
The current version of the WCM, Revision 2, represents a major upgrade of the plugin. Many new features have been added, but some features of the older version have yet to be included. Below is a list of new features, as well as, an estimated time frame for the addition of the unsupported features.
If you are in need of a version of the Wound Composite Modeler which will run on an earlier version of Abaqus, please contact the Center of Simulation Excellence in Lewisville, Texas.
In order to install the Wound Composite Modeler plug-in, click on the link above and save the file to a temporary directory. Then unzip the saved file and copy the resulting folder into the code\python\lib\abaqus_plugins folder of your Abaqus installation.
A WMV-based (Windows Media Audio/Video file) demo of the WCM is available for download. The demo covers the creation of wound composite tanks in two and three dimensions. The full demo lasts approximately 40 minutes
Many applications involving materials like polymers or rubber-filled elastomers demonstrate hyperelastic-finite plastic behavior. The Abaqus Unified FEA suite from SIMULIA currently provides many material models to represent real-world material behavior. However, the existing inelastic models are applicable only where the elastic portion is small and usually linear elastic.
The FeFp model is the first step towards a generalized material model for finite (large strain) elastic-plastic materials. It follows a multiplicative decomposition of the elastic and plastic deformations. Analysts who want to use a material model with a nonlinear elastic finite strain behavior and nonlinear plastic hardening will find the FeFp model useful. A parallel elastic network is included for purposes of modeling a reinforcing phase in the material. The current implementation can be used with solid, axisymmetric and plane strain elements. Rate and temperature dependence are planned for future versions.
The FeFp model is implemented by way of Abaqus VUMAT and UMAT user subroutines. Material model setup is straightforward and does not involve extensive calibration. It can be invoked by either providing material constants or uniaxial test data. The elastic regime needs to be identified appropriately by the user since this data will be used to calculate the elastic and plastic behaviors after yield and during unloading. All test data can be conveniently entered in engineering stress-strain terms.
To define the material model in terms of material constants, as few as 6 parameters are necessary (4 material constants, and 2 flags). In its simplest form, the FeFp model uses two constants to represent the neo-Hookean hyperelastic model in the elastic regime and two other constants for the plastic hardening. The FeFp model also comes with a parallel elastic network whose behavior can be either neo-Hookean or general uniaxial test data. Both the FeFp network and the elastic network contribute a portion of their stress to the overall stress based on user's specified proportion factor. This network is incorporated in the constitutive model to simulate cases where there are elastic inclusions in the overall inelastic matrix. This elastic network can easily be activated or deactivated by a parameter passed into the VUMAT.
In addition to being able to handle simple elastic-plastic behavior represented by the aforementioned 4 material constants, the FeFp network can also model general nonlinear elastic and plastic behaviors. This behavior can be defined in terms of material test data supplied via a separate text file that incorporates the following keywords:
*TOTAL UNIAXIAL TEST DATA Provide the complete engineering stress-strain response with data pairs
*ELASTIC UNIAXIAL DATA Provide the elastic regime data in terms of engineering stress-strain data pairs
*VOLUMETRIC TEST DATA (optional) Provide compressibility data (pressure vs. volume)
Among these specified data, the *TOTAL UNIAXIAL TEST DATA can be data directly from the test. More attention should be given when providing data under *ELASTIC UNIAXIAL DATA since it is used to calculate the onset of the plasticity and the postyielding elastic behavior. In its simplest form, the *ELASTIC UNIAXAL DATA can be specified to be the same as the *TOTAL UNIAXIAL TEST DATA up to the yield point. The *VOLUMETRIC TEST DATA is optional. If it is not used the material is assumed incompressible.
Below is a uniaxial compression simulation using sample compression data from a general polymeric material. As shown, the FeFp material model is able to capture the test data very accurately, even under significant compression. The specification of this FeFp material model was accomplished using the compression test data with the *TOTAL UNIAXIAL TEST DATA keyword and the *ELASTIC UNIAXAL DATA keyword.
Comparison of Compressive Uniaxial Test Data with FeFp Material Model Response
Large strain hysteresis is a common phenomenon of many elastomeric materials. These types of materials generally exhibit significant energy dissipation during cyclic loading. Accurately capturing this behavior can be extremely important for shock and vibration isolation applications. Some applications include shock isolation mounts, bushings, tires, etc.
Large strain hysteresis has been an option in Abaqus/Standard for some time now; however, no analogous model is currently available in Abaqus/Explicit. This extension for the Abaqus Unified FEA product suite by SIMULIA, augments the capabilities of Abaqus/Explicit through a VUMAT material definition which is largely analogous to that provided in Abaqus/Standard through the *HYSTERESIS option.
The Abaqus/Explicit VUMAT supports the polynomial and reduced polynomial forms of the strain energy potential up to order three, along with the form of the hysteresis model that is available in Abaqus/Standard.
Comparisons with Abaqus/Standard
Here we compare results with Abaqus/Standard for simple uniaxial tension, simple shear, and torsion simulations at a cycling frequency of 0.1 Hz. As can be seen, the results compare quite favorably for these simple modes of deformation at low cycling frequencies where inertia effects are minimal.
Next we compare the results for an airspring example simulated at 0.1 Hz and 10 Hz cycling frequencies using:
Abaqus/Standard with Hysteresis [Static step-no inertia effects]
Abaqus/Explicit with no Hysteresis [Dynamic step-includes inertia effects]
Abaqus/Explicit with the Hysteresis Extension [Dynamic step-includes inertia effects]
The results shown for the 0.1Hz case indicate that the spring stiffness is somewhat sensitive to the hysteretic material behavior even at very low cycling frequencies as indicated by the Abaqus/Explicit results without hysteresis.
The results shown for the 10 Hz case also indicate that the spring stiffness is somewhat sensitive to the hysteretic material behavior and also to the dynamics of the system at this cycling frequency. It is interesting to note the high frequency content contained in the Abaqus/Explicit results if no hysteresis is included.