XFLR5 vs CFD

Using SimScale
79

Well things really started going well after you left.

I got rid of everything but the Geometry in the project and I created 4 versions on my new Mesh 1 that has been tweaked with your 7 parameter suggestions:

  1. Change the ‘Max face aspect ratio for layers’ from 0.5 to 2
  2. Change the ‘Max ratio of layer thickness to medial length’ from 0.3 to 0.9
  3. Change the ‘Min face weight’ from 0.02 to 0.002
  4. Change the ‘Min volume ratio between neighbouring cells’ from 0.01 to 0.001
  5. Set the Inflation parameter for 2 layers instead of 3 while maintaining the same overall sum of all layers thickness using the same expansion ratio of 1.1.
  6. This changed ‘Thickness of the Final Layer’ from 0.03821 to 0.06
  7. Decrease the ‘Minimum overall layer thickness’ from 0.02 to 0.0002

I adjusted the Background Mesh Box dimensions slightly.
I added a Mid-Volume Cartesian box to refine an area outside the wing to Level 2 (to help with the isovolume errors that were found).
I used the same Whole Wing Region box to refine the wing to Level 5 as before.
I then used a further 'All Surfaces refinement ’ to Level 8 instead of the Feature Refinement I used initially (this got rid of the refinements at each wing rib.

I then ran simulations on all 4 versions of Mesh 1 and a further Full Resolution Simulation on ‘Mesh 1-1,239,387v 32x16x16’

I looked at yPlus range on simulation ‘0aoa Mesh 1-1,239,387v 32x16x16’ and it looks pretty good I think (would like comment on this please, seems a little low on leading edge):

0aoa%20Mesh%201-1%2C239%2C387v%2032x16x16%20-%20yPlus_on_bottom
0aoa%20Mesh%201-1%2C239%2C387v%2032x16x16%20-%20yPlus_on_bottom513×745 20.2 KB

So then I just put the results in this new chart:

MeshIndependence2
MeshIndependence2979×869 111 KB

Darren, which mesh would you say to use for the definitive CFD results, the converged values or Full Resolution values?

Also, could you do your Paraview isovolume error check on the results?

I will put this data into a final XFLR5 vs CFD comparison chart once we are happy.

Anything else I should do except have a beer now :smile: :beers:

Thanks
Dale

P.S. Now after all that trouble, is there a way to make images that show where the boundary layer precisely separates at this 0aoa and 135mph case (not just particle tracing, maybe like a separation line)?

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