Learning Forum

[Thijs Jansen]

Dear Ansys Fluent Users,

For research at the university, I will investigate the airflow around an air hockey puck above a perforated surface (see Figure 1).

In this model the airflow is supplied from the bottom through the 69 holes with a diameter of 0,5 mm. After this, the airflow enters a cylindrical control volume in which the puck is placed above the perforated surface with a minimum separation of 0,01 mm at the rim of the puck.

Without any prior knowledge on working with Ansys Fluent, I was able to generate the geometry and an initial mesh. However, I found that the element quality at the puck rim is very low (see Figures 2 and 3), as the air film at this location is very thin (= 0,01 mm).

Therefore, I was wondering if anyone has any tips on improving the mesh quality for this case. Especially in the thin film region.

Thanks in advance for your help.

[Federico]

Hello, 

did you use any local sizing at the rim to make sure you can fit cells in there? Face proximity sizing will refine the mesh locally to resolve the thin gap.

[Rob]

I'm also wondering if you subracted the puck volume or not. The image isn't clear.  There are some courses in Learning (left top) and also Tutorials if you click on Help in the software. 

[Thijs Jansen]

The puck volume has been substracted from the cylindrical volume using the Boolean operator in the DesignModeler.

[Rob]

In which case why is the facet size so different to the bulk mesh?