Autodesk Inventor provides some nice options to help you and I out in Autodesk Simulation CFD, especially where rotating regions are required. Fusion is quite nice at doing many things, especially defeaturing / simplification, but in this case, Inventor is my choice.
When developing a rotating component that moves a fluid, one of two options to use in CFD is the rotating region. In using this option, we need to subtract out the mass that is not composed of a fluid; here, the impeller. (We’ll explain why this is important in the coming week, so check in again soon for more CFD goodness).
In the image below you can see the very simple process.
Ribbon –> 3D Model Tab –> Modify Panel –> Combine Tool
The tool requires a Base, and an object to sample for the modification geometry; the Toolbody. Here, we chose the previously modeled ‘rotating fluid region’ as the base. The Impeller was chosen as the geometry sample. This particular example is simply a subtraction.
Notice the ‘Keep Toolbody’ option. This is really important, as I do not want to lose my impeller, but rather to sample it.
When the operation is completed, we end up with a beautiful remaining volume model to feed to CFD as the Rotating Region body. Additionally, the body updates dynamically as the impeller solid is modified.