[noconnor1]

I am trying to mesh a propeller in Ansys and I have really low orthogonal quality around the edges of the blade, please see picture attached.

I have tried adding edge sizing, virtual topology, 'repairing' the geometry in design modeller, removing mesh defeaturing, and more!

Any help would be appreciated, thank you.

[LoGaL]

usually you should have some proximity and curvature settings, so as to decrease the mesh element size around there

[noconnor1]

Hi LoGaL,

Thanks for your suggestion, this is something that I have already tried. Any other ideas?

Thanks

[LoGaL]

you see, the places where you have bad elements are not, as far as I can see, sharp angles, which commonly give issues to the mesher. So the only other possibility is that your geometry is somehow bad there. But it is very hard to see with what you posted

[LondonParker]

Thank you so much for your suggestions.

[Martin_Sz]

Here are some steps you can take to improve the poor orthogonal quality around the edges of propeller blades in Ansys Fluent:

**Meshing Strategies:**

1. **Refine Mesh:** The most common solution is to refine the mesh around the propeller blades. This creates smaller, better-shaped cells that can more accurately capture the flow behavior. You can refine the mesh globally or focus on specific regions around the blade edges where the quality is poor.

2. **Local Sizing:** Utilize local sizing to define a specific target mesh size for the blade edges. This ensures a finer mesh is generated in those critical areas while maintaining a coarser mesh elsewhere for efficiency.

3. **Structured Meshing:** Consider using a structured meshing approach, particularly near the blade edges. Structured meshes offer better control over cell shapes and can lead to improved orthogonal quality compared to unstructured meshes.

4. **Curvature-Based Meshing:** Implement curvature-based meshing techniques that adapt the mesh to the curvature of the blade edges. This ensures the cells conform better to the geometry and avoids skewness.

**Mesh Controls:**

1. **Minimum Cell Quality:** Adjust the minimum orthogonal quality setting in your meshing controls. This sets a threshold for acceptable cell quality. However, be mindful not to set it too high, as it might lead to excessive mesh refinement and longer simulation times.

2. **Avoid Automatic Smoothing:** Automatic smoothing can sometimes worsen orthogonal quality near edges. Consider disabling it for the propeller blade regions and see if it improves the results.

**Alternative Meshing Techniques:**

* **Spreading Function:** If the blade geometry is complex, explore using a spreading function to control mesh growth away from the blade surface. This can help maintain good cell shapes near the edges.

* **overset Meshing:** For complex geometries like rotating blades, overset meshing can be a good option. It allows for independent meshing of the blades and the surrounding fluid, potentially improving mesh quality around the edges.