New Pre-Processing 2406 - Latest Features

This week is the first week after the vacation period (at least in Sweden), and of course we want to welcome you back to work with a new blog post on the Volupe technical blog. In the beginning of July Simcenter STAR-CCM+ version 2406 was released, and there were a lot of useful features for pre-processing introduced.

In this blog post we will take a closer look at one new feature for 3D-CAD, Surface repair and meshing, together with some honorable mentions within these areas.

Geometry handling in 3D-CAD

Let’s start with what you generally do first in the simulation, handling the geometry, within the built-in CAD tool 3D-CAD.

In 3D-CAD the memory consumption is proportional to the number of instances of bodies in your geometry, and that is one of the reasons that it is effective to use multi-instanced bodies. Multi-instanced bodies are interpreted as copies in the code but are still of the same instance. This gives them the possibility of being used as different bodies but requiring less memory, since they refer to only one body representation.

In version 2406 you can utilize the coupling between multi-instanced bodies to create edge/surface/body modifications at one of the bodies and the same modifications will directly be performed on the other bodies. Of course, the option to deselect the instances that you don’t want to include in the operation is available. Note that the default setting is that all instances are included in the selection for the modification. The modifications can for example be adding a fillet or imprinting a sketch.

To import multi-instanced bodies without losing the connection between them you tick in the option “Import Multi-instanced Bodies” while importing (see picture below). When selecting a body in 3D-CAD you will see if the body is of type “multi-instanced” in the property window, where a greyed-out tick-box will be enabled if true.

Honorable mentions in 3D-CAD

Exploded view: For more user-friendly visualization – scaling of the distance in the exploded view can now be performed by dragging a pointer on a scale, where the option of uniform scaling in all directions can be enabled.

Color import in 3D-CAD from clients: Color coding can be imported together with geometries for clearer visualization and kept labeling.

Geometry clean-up in Surface repair

When investigating/manipulating the surfaces of your geometry in Surface repair you can select all triangles located on one surface by double-clicking at any triangle. If your surface is not flat all the way out to the boundaries you can end up needing many clicks to select all the remaining triangles of interest. If the selection looks like in the left part of the picture below you can add this selection, by clicking “Add selection”, and then click on “Cleanup boundary” to automatically select all the triangles up to the boundary. If desired the cleanup boundary feature can also be used to deselect triangles if that mode is enabled. There are settings for angles and distances criteria deciding the classifications of triangles/surfaces.

Honorable mention in Surface repair

Part surface mode in Bounded shape operation: bounded shapes are connected to the reference part, and now you can also create bounded shapes based on each part surface within a part (previously you could only create the bounded shape based on the complete part).

Meshing – discretizing the fluid domain

Adaptive mesh refinement (AMR) is a useful feature which remeshes and includes refinements based on where gradients in the result are high, therefore only spending fine cells where they are actually needed. This makes AMR increase accuracy, improve efficiency, reduce memory usage, and enhance scalability in your simulation.

One part of the mesh where AMR previously has had a potential for improvement is within the prism layers. Isotropic refinement has been used so far and it can result in more cells than actually needed, together with lower quality of the cells than desired. In Simcenter STAR-CCM+ 2406 the possibility of anisotropic prism layer refinement in AMR is introduced. Settings within AMR for choosing and adding properties using isotropic, tangential, normal, or criterion-based refinement strategies will from now on ensure more efficient and accurate boundary layer capturing. The possibility of disabling the refinement is also available.

Normal refinement allows for cells to be refined in the direction normal to a wall boundary. Tangential refinement allows for cells to be refined in the direction tangent to a wall boundary. And with the criterion-based refinement, users can choose which refinement strategy should be employed on which wall boundary. In the picture below an airfoil leading edge is meshed using different types of refinement. To the left you see isotropic refinement (from the second newest version, 2402) and in the middle and to the right you see the new features normal and tangential refinement (from version 2406).

Honorable mentions for meshing

Aspect ratio control for Advancing layer mesher (ALM): More flexibility and control when generating prism layers with ALM is now implemented. The aspect ratio, defined as the ratio of thickness between last prism layer cell and local surface mesh size, which can be limited between the values 0.5 and 3 is now available as setting to select.

Conformal poly/prism mesh with isotropic quad-dominant surface mesh: Enabling “Quad input surface conformality” in the polyhedral mesher when using quad-dominant surface mesh you will now obtain a conformal mesh to the surface – providing the highest quality of mesh.

We at Volupe hope that this blog post about the new pre-processing features in Simcenter STAR-CCM+ gave you a good understanding of how to utilize the new 2406 version of the software within your daily work. If there are any questions about the features, please reach out to us at support@volupe.com.

Please also have a look at the other new features of version 2406 at the Siemens blog post https://blogs.sw.siemens.com/simcenter/simcenter-star-ccm-2406-released/ which inspired this Volupe blog post.