Below is a list, in no particular order, of behavioral questions frequently asked abut the Ansys DesignModeler application.

Why is a regenerate sometimes required when I open a database?

When creating the model, DesignModeler creates "rollmarks" in between each feature. A rollmark is a marker in the geometry engine that allows the model to be rolled back to that point in the model’s history. Whenever you click the Generate button, DesignModeler searches for the first feature that was modified, and using its rollmark, rolls the model back to that point in history so that it may regenerate the model from that point onwards. Without rollmarks, the entire model would need to be rebuilt every time you click Generate.

Beginning with release 12.0, a Rollmark Management Model Preference allows you to specify the extent to which rollmarks are saved to the DesignModeler database. The default is that a partial list of rollmarks are saved to the database, with the result being that when this database is loaded no regenerate is usually required. Other possible values for the Rollmark Management Model Preference include the option of saving no rollmarks. In this case, a regenerate will always be required when the database is first opened. Other options allow either all rollmarks or a subset of rollmarks to be saved. Thus it may be the case that if an existing feature is modified or a new feature inserted that previous features without rollmarks might also require regeneration. Finally, it is noted that rollmarks were not saved to the DesignModeler database prior to release 12.0, thus a full regenerate is required for all such databases after they are loaded.

Why don’t some features highlight any geometry in the graphics window when I select them in the Tree Outline?

Each model entity carries an internal persistent label, which is based on the feature that created it. Some features, such as Face Delete, do not create any new topology, so there is nothing on the model to highlight when the feature is selected.

What does the "…" mean in the Details Box when viewing body properties such as volume and surface area?

This means the value has not been calculated. DesignModeler will automatically calculate volumes and surface areas for bodies with a small number of faces. For bodies with large numbers of faces, the calculations are skipped to save time. The volume and surface area properties may be calculated on demand using the Measure Selection right mouse button option.

Why do the volume and surface area properties report ‘Unknown’?

This means the values cannot be accurately calculated. This can occur when the body contains model faults or has geometry that could not be faceted.

Why can’t I place a sketch instance in a plane that appears above the base sketch in the feature tree?

Each feature and sketch in DesignModeler contains a list of dependencies. A dependency can never appear below the object in the feature tree, meaning a feature or sketch can never be dependent on something that gets created later. It may only depend on geometry that was created earlier in the model’s history. Likewise with sketch instances, DesignModeler never allows a sketch instance to be placed in a plane prior to the plane containing the base sketch.

Why can’t I delete items used for a Sketch Instance or Projection?

Once you create a Sketch Instance or Projection in a plane, you cannot delete the base items as long as the Sketch Instance or Projection exists. In fact, just deleting the instance or projection is not enough to allow the base items to be deleted. This is because you could still do an "Undo" to restore the instance or projection. If you delete the plane that contains the instance or projection, that will free up the dependence on the items because the Undo and Redo stacks for that plane are cleared. Another way to clear the dependence is to Save via the File Menu since that clears the Undo and Redo stacks for all planes.

When restoring an auto-saved file, why doesn’t the agdb-00 file appear in the list?

The auto-save is performed once every few Generates, according to the frequency defined in the Options dialog. Immediately after auto-saving, the model is in the exact same state as the agdb-00 file, so it is not shown in the restore menu. Once the model encounters another Generate, the agdb-00 file will then become available for restoring.

Why is it that I can see the preview for an Extrude or Revolve feature, yet when I click Generate, the feature reports an error indicating intersecting profiles?

The feature previews simply display the edges from your selected base object in a translated or rotated manner to give you an idea of what the feature may look like when it generates. Profiles are not checked for errors, including intersections, until generate time.

Why did my feature fail due to non-manifold geometry when all I did was a Thin/Surface operation on a single body?

This might be due to other active bodies present in the model. When the Thin/Surface feature executes, a Boolean operation is performed where it will attempt to merge together all active bodies in the model. If you imported or attached geometry using the Add Material operation, try switching it to Add Frozen. This will prevent these bodies from being merged together.

Why is my model displayed so poorly in the graphics window?

This is due to your Facet Quality setting in the Options dialog. If this setting is too low, your model’s curved surfaces will look blocky. You can improve the display by increasing the Facet Quality setting, although it will require more memory and may take longer to generate model facets.

Why does it take so long to generate model facets?

Large models often require many facets, so generating them can take awhile. For very large models it may help to turn down the Facet Quality setting in the Options dialog. Doing this will save some time and memory.

When I uncheck a parameterized property in the Details View, why doesn’t the DesignModeler application delete that design parameter from its parameter manager?

When checking and unchecking Details View properties, DesignModeler creates assignments that bind those properties to specific design parameters. The design parameters can be assigned to many different feature properties, so DesignModeler does not automatically delete them. In addition, when you uncheck a driven property, DesignModeler leaves the assignment in its parameter manager, but in a commented state. That way, if you decide to reactivate the driven property, all DesignModeler needs to do is uncomment the assignment in its parameter manager. Remember that you can always manually edit the parameter manager assignments however you choose.

Why did my feature fail due to a model size box error?

DesignModeler’s workspace is limited to 1 km³ in size, centered at the world origin. Your model cannot exceed this size box or it will generate an error. If you enable the "Large model support" option, the model size box limit changes to 1000 km³. See the Model Size Box section for more details.

Why does the agdb file get marked as modified in the Project Schematic whenever the model is transferred to the Mechanical application?

DesignModeler needs to perform some postprocessing on the model when it is transferred to another application. Included in this process are edge joint processing and shared topology for multi-body parts, which may create new data objects in DesignModeler. It is strongly recommended to save the agdb file, especially if it is the first time the model was transferred to the Mechanical application.

Why did the Mid-Surface feature fail to detect face pairs that appear to be of uniform thickness?

There are several reasons the Mid-Surface feature may miss face pairs the user had intended to select. First, the thickness of the face pair may not be within the range specified by the maximum and minimum thresholds. Second, the geometry may not be analytic. If you simplify the geometry in your Import or Attach features, this may correct the problem. Third, though it may appear to be of uniform thickness, the faces in the pair may not actually be perfect offsets. The tolerances for uniform thickness are rather strict.

Why can't I stitch together line body edges that were created by the Lines From Edges feature?

In some cases, DesignModeler may not be able to stitch together line body edges that are created from existing model edges that are defined by NURBS curves or imported geometry. The reason for the problem is that some NURBS and/or imported geometry is defined with looser tolerances. When line body edges are extracted from these original model edges, they are not within DesignModeler's default tolerance and can sometimes fail to merge together during Boolean operations.

Why did I receive an out of memory error?

Sometimes the system can encounter an error when a large model or a high graphics resolution demands more memory than the system can supply. When the error occurs, DesignModeler will provide you the option of saving the current database with file extension "agdb.bak". To remedy the problem, you can lower the graphics resolution or try importing fewer parts into DesignModeler.

Why are commas not recognized in numerical formats within Ansys DesignModeler on the Linux platform for French and German locales?

Specific to the Linux platform, if you are using a localized operating system (such as French or German), or set your preferences to use regional settings for numbers and dates (comma delimiter versus period), then you may need to modify an additional setting to get numeric values to appear in the proper form. For more information, see the Platform Details section of the Ansys, Inc. Linux Installation Guide.

Why doesn't the screen capture utility work?

The Aero display mode in Windows 7 is incompatible with the screen capture used in Ansys Workbench. For users running Windows 7, turning off Aero mode will restore this capability.

When using a localized version (for example, Japanese) of DesignModeler, why do the features in the tree outline change to English?

Feature names can contain only letters/digits (for example, a..zA..Z0..9) and must begin with a letter to be locally translated. The following known limitations apply to specific languages:

Why is my file name illegal?

You may encounter a file that will not open or save when there is an illegal character in the file path or file name. Such examples would be:

This error can be corrected by modifying the name of the offending folder or file.