[Zen]

How can I output the wall shear stresses to plot surface streamlines?

Thank you,

Zeno

[Zen]

To plot the surface streamlines with the data files su2 outputs you need to merge the surface_flow.dat file and the flow.dat file in one single .dat file.

For example, copy-paste the flow.dat file to the bottom of the surface_flow.dat file (in this way the flow zone is identified as zone number 2), and add the following lines just before the start of the surface data:

PARENTZONE= 2, %it identifies the zone number 2 (the flow zone) as the parent zone
AUXDATA Common.BoundaryCondition = "Wall"
AUXDATA Common.IsBoundaryZone = "TRUE"

If you then load this file into Tecplot, you'll be able to plot the surface streamlines on, for example, a wing.

[hlk]

Thank you for posting the solution to this problem.

[DLuo]

This looks like a Tecplot specific solution. If I remember correctly, Tecplot will allow you to use velocity vector in the first cell off of the surface to plot Shear Stresses.
I'm not positive Paraview has a similar feature. Is there a way to natively output Tau vector into the surface.vtk file?

[hlk]

Originally Posted by DLuo

This looks like a Tecplot specific solution. If I remember correctly, Tecplot will allow you to use velocity vector in the first cell off of the surface to plot Shear Stresses.
I'm not positive Paraview has a similar feature. Is there a way to natively output Tau vector into the surface.vtk file?

Thanks for your question.
The easiest way to do this will likely be to postprocess the surface_flow file: the momentum components (density*velocity, labeled CONSERVATIVE_2 - 4), the density (CONSERVATIVE_1), and the skin friction coefficient are included in the output, so you should be able to get the tau vector from those components.
Also, the components of momentum (conservative_2-4) may also help with this plotting problem directly.

Alternatively you can code this in yourself by editing output_paraview.cpp and adding the tau values to the Data array in output_structure.cpp - however that will be more complicated and if you are not careful may produce code which works for your case, but produces unexpected output in other cases.