Importing and Exporting Steps using HyperMesh

One of the key features of Altair HyperMesh is that its CAD and Solver agnostic, which means it fits easily into most workflows. With this compatibility comes the ability to import and export models from and to varying sources. This blog post looks at the detailed process of importing geometry files and exporting FE models using Altair HyperMesh, highlighting best practices and tips to ensure smooth transitions between different stages of your simulation projects.

The process of importing models into HyperMesh is straightforward but requires attention to detail to ensure that the model data is correctly interpreted and utilized within the software.

Import Options

The first step in importing a model is to determine the format of your existing model file. HyperMesh supports a wide variety of file formats, including native CAD formats like CATIA, Creo, NX, and SOLIDWORKS. It can also import neutral file formats like STEP or IGES as well.

Before importing an actual file, let’s look at the CAD Import Options. To find Import Options, go to File > Preferences > Geometry > Import Options as seen in Fig 1 below.

Fig 1: CAD Import Options

In the import options, users can define universal import specifics, including measurement units, scale factor and geometry cleanup tolerance. In addition to that, you can also specify import specifications that are dependent on the type of file being imported. For example, if you notice one file type giving more geometry-related errors on import, you can change the geometry cleanup tolerances for just that format and leave the rest of the formats at the general settings.

Importing Geometry

To import a CAD file, go to File > Import > Geometry Model (as seen in Fig 2 below.) or CTRL + I to open an explorer window.

Fig 2: Geometry Import Location

Another option is to drag your file and drop it into the open space in the HyperMesh interface. If you do this, you will get a Load File menu (Fig 3) with the option to choose the type of file (file type should be automatically detected, but can be changed in this menu) and whether you want it as a new model or merged with an existing model.

Fig 3: Load File option when dragging and dropping

Managing Assemblies

When importing assemblies, HyperMesh has a tab on its ribbon titled “Assembly” that gives users specific functions related to these files, seen in Fig 4. Most of these functions help organize assembly files and their associated part files. Let’s look at a few of the functions in more depth.

Fig 4: Assembly Ribbon in HyperMesh 2023

Match Function

The Match Function automatically group selected parts into part sets based on comparison method and criteria selected. Parts can be matched by shape or metadata using AI algorithms, then linked so changes made to one part affect the corresponding matched parts. Users also have the option to adjust the similarity percentage to capture all near perfect matches as well. This can be helpful when working with large assemblies that contain many similar parts that require repair or slight changes.

Fig 5: Match Part options

Manage Section

The Manage section of the Assembly tab gives a few options on how to manage parts and subassemblies in a more efficient way.

• Parts: A browser to create, organize and manage CAE part structure and hierarchy.
• Subsystems: Create, organize and manage CAE subassemblies to make large assemblies more manageable.
• Mechanism: Allows users to create a kinematic or motion mechanism based on FE mesh.

Fig 6: Assembly Manage Icons

 Comparison

The Comparison tool allows you to compare two assemblies, components, or models to identify differences. These differences could be in terms of geometry, mesh, properties, materials, or any other attributes. It highlights what has changed, added, or removed between the two versions.

Fig 7: Comparison between two models using Assembly Comparison Tool

The comparison tool can be helpful when trying to understand differences between different versions of a model or the evolution of its design and identify unintended changes or errors during rebuilds.

Exporting using HyperMesh             

As mentioned above, one of the strongest benefits to using Altair HyperMesh is that is both CAD and solver agnostic. While we covered the importing of geometry models, now let’s talk about the process of exporting from HyperMesh to a solver.

While Altair has some very powerful solvers like OptiStruct, Radioss and Acusolve, HyperMesh can also export to other industry solvers like Nastran, Ansys, LS-Dyna and Abaqus. Each one of these solvers has specific settings that need to be considered when preparing your HyperMesh model for export. To see more detail about each solver, check out the Altair HyperMesh Help option.

Before getting to the Export step, users should change the Solver Interface they are preparing for. You can do this by going to File > Solver Interface > Solver of choice.

Fig 8: Solver Interface Menu

Once your model is setup with the specifics for your solver, you can export the file by hitting CTRL + E or going to File > Export > Solver as seen in Fig 9 below.

Fig 9: Export Menu

If you have already set up your FE model for OptiStruct or Radioss and want to convert it to be used by another solver, that’s a simple process as well. Go to File > Convert > Solver Options as seen in Fig 10 below. Once you choose your solver, a menu will appear with conversion options and the ability to review all entities before starting the conversion process.

Fig 10: Convert Solver Menu

 As mentioned, HyperMesh is known for its powerful preprocessing capabilities, but its compatibility with nearly all workflows means it can be included without much disruption. It’s ability to import most geometry files and export to all common solvers means you can maximize the investment in your current tools, but with the licensing structure of Altair Units, you can also take advantage of the powerful set of solvers included in the HyperWorks interface as well. If you have any further questions don’t hesitate to let us know.