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The essential steps in mesh generation are the same, regardless of the mesh type. About 80% of any meshing process is executed using only 20% of the software's functionality, and the most traversed steps are:
These steps leave much of the mesh generator's functionality unexplored, especially the powerful lot of Fidelity Pointwise's commands that can speed up the entire process. Below is a list of 8 powerful commands on Fidelity Pointwise that are less explored and can do wonders!
Fidelity Pointwise's Examine command (for visualizing mesh quality metrics) provides five choices for color bars (aka ramps) (see Figure 1), which includes the ability to reverse each of them. Unfortunately, not many users are aware of this capability. Figure 1 illustrates Pointwise's five color bars: Spectrum, Full Spectrum, Modern, Red-Blue, and Grayscale. A quick comparison reveals that the Grayscale might address the concerns with rainbow color maps that are often said to be "confusing, obscuring, and actively misleading." Regardless of the user's preference, they are available to all.
Figure 1. The minimum included angle for an unstructured grid around an airfoil is displayed using the different color bars - Grayscale (upper left), Spectrum (upper right), Modern (bottom left), Full Spectrum (bottom center), Red-Blue (bottom right).
How can there be anything different with the delete option? Well, there's a big difference between the Delete (Del) and Delete Special (Ctrl+Del) commands. For example, on selecting a block and pressing Delete, the block gets deleted while its parent entities (domains and connectors) remain. In case an entity and its parents are to be deleted, the Delete Special command must be used because it applies to all topological entities, from models and quilts to blocks and domains.
Undo (Ctrl+Z) in the Edit menu is one of the favorite commands among users. The reason should be obvious: Undo allows the user to recover from mistakes or unexpected results. Depending on how error-prone or conservative the user is, one can set the number of Undo levels in Pointwise to as high as 20. The default value for the number of Undo levels is five. The number of levels is simply the number of commands that can be undone relative to the grid's current state.
Undo in Fidelity Pointwise is implemented as a state machine rather than by reversible commands. Pointwise has to store the changes between successive states – in other words, the differences between the grid at each undo level. Furthermore, the differences are stored in memory and not rolled off to disk. The flexibility of retaining 20 undo levels must be weighed against increasing memory usage's negative impact. One might consider reducing the number of undo levels to only one to enjoy the best of both worlds – the ability to recover while minimizing memory usage.
There are instances where a command on the toolbar behaves differently than the same command in the menu. Intersect is one such command. Intersect computes the intersection of all entities in one set (Group A) with all the entities in another set (Group B). The faster way to intersect the two entities is to select them both and press the Intersect button on the toolbar. The toolbar implementation of Intersect computes the intersection of each selected entity with all other selected entities without opening the command panel.
Assembling models can be performed interactively by selecting various CAD surfaces and setting a tolerance, but that can often involve trial and error, depending on the CAD data's source and the user's comfort using the CAD file. In cases where you are familiar with the CAD data, you can have the model assembled automatically during CAD import.
For example, consider the mechanical part in Figure 2. By default, the CAD data is imported without automatically assembling the solid model. The imported model shows more than 60 disconnected surfaces (denoted by colors).
To assemble the model automatically, use the panel's Model Assembly Tolerance option. As long as the tolerance is set to a positive number, the code will attempt to assemble the solid model(s) automatically.
Figure 2. By default, a CAD part is imported without assembling, resulting in more than 60 individual surfaces (left). The CAD data is automatically assembled into a single, watertight model (right) by setting the appropriate tolerance.
Figure 3. The Print to File Setup command gives you options for saving image files, including the ability to render at higher than screen resolution.
The Print to File (Ctrl+P) command captures the Display window image and saves it to a PNG, BMP, or TIFF image file. But with the Print to File Setup (Ctrl+Shift+P) command, the image to be saved can be customized. The Colors frame in Figure 3 gives control over the image's foreground and background colors. More interesting controls are available in the Advanced frame, where users can create an image file at a higher resolution than what is seen on the screen.
Users encounter several challenges during mesh generation, even after the CAD data is imported accurately. One such challenge is the inclusion of excessive details. These details (small holes, for example) complicate mesh generation.
The extruded lettering is often an unnecessary feature while meshing a model and can be removed easily using the Untrim command. For example, in Figure 4, if surfaces that comprise the raised lettering were deleted, the endplate of the engine block would still have three holes and cutouts for each of the letters (left). Instead, it is possible to untrim the endplate by removing the curves that define the shapes of the letters, leaving the endplate untrimmed (right). To accomplish this, select the endplate's quilt and press Edit, Untrim. You see the quilt's trimming curves highlighted. Select those curves and press Untrim.
Figure 4. The difference between deleting (left) and un-trimming (right) when it comes to removing excessive detail.
One last powerful yet lesser-used command is Zoom to Selection (Shift+F2). If you want a closer look at one particular entity, the easiest way is to click on the entity and use the Zoom to Selection command in the View menu. The selected entity (or entities) will be positioned to fill the Display window.
Explore these 8 powerful commands next time you try meshing on Fidelity Pointwise!
To learn more about these 8 unexplored commands on Fidelity Pointwise, read The 8 Most Helpful Commands You're Not Using by clicking the button below.