
Over the years, computational fluid dynamics (CFD) software has simplified the prepping and meshing of fluid models — making CFD technology more accessible to the general engineering community.
Here are three best practices for simulating fluid models. For six more examples, check out ANSYS Advantage, Issue 2, 2019.
1. Use Geometry Wrapping to Create Watertight Fluid Models
The geometry that designers send to engineers is rarely clean enough to import into a fluids model. Fixing these gaps and leaks in the geometry can traditionally take hours, even days.

Therefore, engineers should use a CFD software that can wrap a surface mesh around discontinuous geometry. This meshing capability will quickly fill in all the gaps, leaving more time for simulation and results generation.
For example, ANSYS Fluent’s fault-tolerant workflow for non-watertight geometries can create that surface mesh wrapper.
2. Combine Overlapping Geometry to Quickly Create a Flow Boundary

Engineers can use ANSYS SpaceClaim to clean up geometry. Its pull, move and combine tools can close gaps and remove intersections between solid assembly bodies.
After that, engineers can extract the flow volume from the solid geometry by creating an enclosure around it (for external flows) or capping openings (for internal flows).
If engineers require multiple regions to model solid conduction or porous media effects, they can use the Share Topology function to connect the geometry into a watertight model. Inside Fluent, engineers can generate surface and volume meshes using new task-based workflows.
3. Utilize Parallel Processing to Speed Up Mesh Generation
Engineers can use parallel processing to speed up the generation of Mosaic poly-hexcore meshes. To date, some mesh generations have been sped-up by a factor of 10.
Engineers can use up to 64-cores to utilize this tip. The cores can be on a laptop, or cluster, and can be utilized without a high-performance computing (HPC) license.

ANSYS Fluent’s Mosaic-enabled meshing technology can automatically link these grids using a poly-hexcore mesh. Any type of mesh can be connected using this technology, including:
- Tetrahedral meshes
- Hexcore meshes
- Polyhedral meshes
To learn six more tips to simplify the creation of fluids models, read: Get the Most Out of the ANSYS Fluent Task-Based Workflow within ANSYS Advantage, Issue 2, 2019.
To learn how democratizing the CFD workflow can improve the design cycle, read: Improve Workflow, Improve Productivity within ANSYS Advantage, Issue 2, 2019.