CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   ANSYS Meshing & Geometry (http://www.cfd-online.com/Forums/ansys-meshing/)
-   -   [ANSYS Meshing] Is an inflation layer necessary? (http://www.cfd-online.com/Forums/ansys-meshing/121454-inflation-layer-necessary.html)

ziggo July 29, 2013 09:12

Is an inflation layer necessary?
 
I'm doing a CFD calculation of a one element of a tetrahedral kite (the image shows four elements) and I wonder if it is necessary to include an inflation layer on the lifting surface.

The flow is turbulent and I'm using a k-epsilon standard model.

Without the inflation layer, I have got reasonable results for a high angle of attack (AoA as defined here), but when lowering the AoA, the results get worse.

Would using an inflation layer on the wall improve my results?

flotus1 July 29, 2013 12:07

Definitely.
Doing CFD near walls without some kind of prism layers is like rolling dice.

ziggo July 29, 2013 12:13

Thank you for your reply. For some reason rolling dice gives me quite reasonable results for high angles of attack, so that's why I wondered if it was necessary at all to include prism layers. But apparently it is necessary.

flotus1 July 29, 2013 12:16

For high AoA, the shear is less important than the pressure.
The pressure field may be resolved sufficiently with an all tet mesh, but the shear rate near the wall needs a better mesh.


All times are GMT -4. The time now is 11:34.