ANSA is the culmination of over 30 years of research in the CAE field. The implementation of novel concepts such as topology and geometry abstraction initiated its current course of adoption in the CAE industry. Although ANSA started in the Automotive industry, it is now widely used across many industries in all aspects of model preparation.
ANSA is the leading multidisciplinary CAE pre-processor. It provides all the functionality required to build models, from CAD Import to ready to run CAE models in an integrated environment.
It provides a fully customizable GUI which allows Users to customize the interface based on their role and analysis tasks. A native look for each platform is provided, with drag and drop window functionality for docking and custom shortcuts, all stored inside an XML settings file for later use.
The level of detail in visualization is used to enhance the speed with which ANSA can handle large model sizes without penalty. This attention to detail is reflected in all aspects of development.
The User interface has been designed to reduce the user interaction and provide consistency in operation. The layout provides direct access to functionality through an entity type grouping. Undo/Redo functionality and standard interface norms allow Users to master the tool without concern of making mistakes. The extensive step-by-step tutorials and User Manual provide detailed explanations of the functionality.
CAD Data Input and Geometry Tools
ANSA supports reading most major CAD formats through direct import. Interfaces to PLM tools allow ANSA to maintain the CAD product structure in the CAE environment, while allowing the analyst to build the corresponding CAE specific data structure for the solver. This unique ability to handle both sides of the process positions ANSA as the pre-processor of choice for bridging the gap between CAD and CAE.
Multiple tools are provided to prepare the geometry for the appropriate analysis. Handling of topological issues such as cracks, gaps, overlaps, untrimmed faces are identified a treated through the Checks Manager. Feature identification tools are provided to quickly treat specific features. Automatic mid-surface creation is available for complicated non-manifold topologies.
ANSA also provides the tools necessary to manipulate existing geometry or create from anew, thus allowing the analyst to not only report on existing design, but lead the design process.
ANSA Data Management
As ANSA is the bridge between CAD and CAE Solvers, it possesses multiple ways of managing the data. The Part Manager is used to maintain the link with the CAD system, and the Properties, Materials and Sets are used for the solvers.
By maintaining the link with the CAD system, it allows for easy model updates and comparisons. Similarly, some parts require multiple property definitions, such as tailor-welded blanks or plastic parts of varying thickness. This can be achieved while still treating them as a single part per the CAD definition.
A further extension, ANSA allows this data to be stored and retrieved through the ANSA Data Management utility, allowing analysts to build multiple representations for the same model. These different meshed representations allow the User to fine tune a model for accuracy and solution speed without losing definition. Different representations can be built on the fly, from mesh representations using the Batch Mesh Manager to reduced representations such as lumped mass.
Model Comparison and Update
The compare tool can efficiently compare the geometrical differences between two models, be they geometry, mesh or a combination. This can be extremely useful to compare a new data set against an existing FE model such that only the changes need to be incorporated.
Also taken into account is a comparison of the attribute data, such as Gauge, Material, etc. so that the User can monitor changes that are made during the design phase.
A PPTX/PDF report is created automatically that identifies the differences between the two models.
There are two mechanisms for the automation of processes inside ANSA. These are the Task Manager and Scripting.
The ANSA Task Manager is a tool that organizes all of the distinct modeling actions that must be followed for the setup of a discipline specific model. It is designed to be setup by the User without requiring knowledge of scripting, and can handle most major structural solvers from model preparation to export of the Solver deck.
ANSA Scripting is a programming environment that enables the development of complex custom procedures which utilize both the existing capability of ANSA as well as user developed functions. There are two languages available, BETA scripting and Python. The use of external Python libraries greatly enhances the extendibility of the automation capabilities.
ANSA provides many fully automatic and semi-automatic meshing tools. At the core of these tools are the unique proprietary meshing algorithms which are fast & robust and the Reconstuct/Reshape tools which allow the manipulation of mesh for improved mesh flow and quality.
These tools can be used interactively or through the Batch Mesh Manager which integrates the tools to deliver a high quality result based on the User requirements.
Treatment of CAD and existing legacy FE data can be handled through the tools, thus allowing an analyst to quickly coarsen or improve a mesh flow from an existing model.
For water tight surface definitions, the Wrap tool can be used to quickly generate a high quality surface mesh based on User parameters without requiring extensive geometry manipulation.
Volume meshing algorithms including fully automatic top down approach such as Hextreme which yields a hex dominant mesh with cut cells at the surface, and bottom up approaches using Tetrahedral, Pentahedral and Hexahedral elements. Layer generation is also possible with many controls for prism height, growth and control of quality.
An Acoustic Cavity tool is available which provides a step by step wizard in generating the acoustic cavity mesh for Nastran or PERMAS. The analysts have control over the size of elements, number of sensor points and locations, the type of connection between the solid elements and the wetted surfaces. Also it can automatically create/update the appropriate ACMODL solver card.
ANSA uses geometric entities to define the assembly data. This geometric abstraction is a concept prevalent through many tools, where the information is assigned to a geometric entity and the analyst can then represent that entity differently based on the analysis they will perform.
Point, Curves and Faces are used to define Spotwelds, Rivets, Bolts, Seamwelds, Adhesives, Gumdrops, and many other types of fasteners inside ANSA. These are managed through the Connection Manager, which allows the analyst to define templates and use multiple built in definitions for the different FE representations. This data can be imported through connection files, or exported to be shared with other Users.
For more generic definitions which allows greater flexibility in representations, ANSA provides the ‘Connector’ entity. This entity is fully customizable, and can be configured to connect subsystems together, utilizing built in representations, scripts or even library items.
ANSA supports the include keywords, and provides the requisite tools to create, manage and output the include files from the database. Include files allow the analyst to break up the model into smaller sections thus only needing to update a portion of the model that incur changes.
Extending this further, ANSA provides the Includes Configurator, which allows the User to select from multiple include files for a given loadcase. This allows quick and easy definition of multiple variants of a model to be analyzed and their corresponding load cases.
ANSA pioneered and successfully implemented the concept of interoperable decks between the supported solvers. This allows the user to directly switch between solvers with all supported entities mapping automatically and even synchronization of material information.
The keyword cards in ANSA are interrelated and inter accessible. This enhances the ability to create and reference entities on the fly. Assistance for NASTRAN, LS–DYNA, ABAQUS, PAM–CRASH, RADIOSS & OPENFOAM have been intelligently included in ANSA so as to provide the user with tool tips for all the keyword cards. The tools tips are a direct replica from the user manuals of the respective solvers. This not only increases the productivity of the user with rookie knowledge of the solver decks, but enhances the model accuracy as well.
As with Connections, the concept of referencing FE entities through geometry equivalents has been further explored and efficiently used in the handling the various other solver specific entities. This has proved to be as major benefit in mass trimming, output request creations, boundary conditions definition & set creation and maintenance. ANSA’s scripting abilities further enhances its ability to handles them on a massive scale and thus help in data roll-overs from legacy models with outstanding efficiency.
The Laminate Tool is one more enhanced function that assists the modeling of complex parts made of composite materials. A single interface suffices the operation of creation & modification of layers, material orientation and definition of stack orders. This is common between NASTRAN, ABAQUS (Standards/Explicit), LS – DYNA, RADIOSS & ANSYS decks. It encompasses the ability to create laminate properties & layers on the fly, off an existing FE entity or can read a NASTRAN PCOMP layers from legacy models to generate corresponding properties.
Based on unique needs of the crash & safety engineering community ANSA has built and integrated semi-automated tools to help in creation of occupant safety models. These tools are include features for impactor positioning, seatbelt fastening, positioning and articulation of crash test dummies and “head form” models for passenger and pedestrian safety simulation standard scenarios.
Model Integrity Checks
Prior to exporting a model for solution, ANSA provides various model checks to ensure model integrity and accuracy. These can be run individually or through a template, which will run all checks at once and provide an overview of the model quality. The User can fix many of the issues automatically through the Model Check tool, or interactively with the help of the tool to isolate the problematic regions.
To setup the model for analysis, ANSA provides the requisite tools for solution control based on the respective solver, Nastran Header, ABAQUS STEP Manager, LS-Dyna Control Cards, etc. The following solvers are supported to output a ready to run model; NASTRAN, LS-Dyna, PAM-CRASH, RADIOSS, PERMAS, ABAQUS and ANSYS. Numerous other formats are supported for the import and export.
The morphing tools are fully integrated in the ANSA environment. Morphing can be used to modify existing designs, link with optimization, or create new concepts for future studies. The application of morphing can be found for all disciplines: Crash, NVH, Durability, CFD, etc.
There are two main methods implemented inside ANSA; Domain based and Direct Morphing. These work on both Geometry and FE model data. Domain Based morphing requires the definition of control boxes assigned to the model in order to manipulate the shape. As the boxes are abstract, it provides significant flexibility and robustness in handling the most complicated cases.
Direct Morphing works with existing features of the model thus reducing the effort and complexity required to make alterations.
ANSA provides many advanced tools for specialized tasks, including a Cross-Section, Fuel Tank and Volume Trap tools.
The Cross-Section analysis tool calculates the geometric properties for both thin and thick section. The sectional properties can be used to create Beam/Bar properties to be used in the respective solver Deck.
The Tank tool generates a numerical analysis of the Volume vs Height of the fuel in the tank. This can be done for multiple orientations and helps determine the optimum filling and suction points.
The Volume Trap tool investigates regions of trapped liquids during the immersion and extraction of the BiW (Body in White) bath analysis.
One of the biggest advantages that ANSA delivers is the ease with which it can be coupled with an optimizer. An optimization task is a pre-processing sequence that works based on design variables, while following certain design constraints to achieve the final design objective.
Any attributes inside ANSA can be made into a design parameter to be used by external optimizers. Morphing parameters can also be used to in the optimization task as a design variable. This facilitates:
- Shape Optimization
- Topology Optimization
- Gauge Optimization
- Spot – weld Optimization
- Composite Optimization
The coupling of ANSA with an optimizer has been implemented in most 3rd party optimization software as ‘nodes’ or ‘modules’. These can be called from the respective software when setting up the optimization process.
This is a result of an out of the box approach to solving problems in accurately positioning complex subsystems & components based on the rigid body dynamics. The tools incorporated functions which create rigid body definitions for corresponding FE entities with minimum user interaction.
A fully integrated Multi Body Dynamics Solver then utilized the kinematics relations between these rigid bodies to solve for complex positioning and modeling scenarios. These tools bring a great advantage to the user especially involved in modeling seat – dummy positioning, suspension system models, retractable roof systems and other mechanisms.