How can I extract the Cp distribution plot around an airfoil from a VTK file using Paraview?

Victor · August 7, 2020, 9:58am

I have seen in other discussion pages that they can do it extracting the block or selecting the surfaces of the airfoil. However, in my VTK file I do not have those. I only have the fluid domain around the airfoil. Does anyone know how to extract the pressure distribution around an airfoil with the domain file I am attaching below?

Thank you in advance.

domain_00000080.vtm (4.0 KB)

mwestphal · August 7, 2020, 11:28am

You need to share the associated files : domain*.vti

Victor · August 7, 2020, 3:55pm

Thank you Mathieu. However, the software I am using to perform the simulation (called PALABOS) only generates .vtm files in this example. Is there something that I could do with the .vtm files?

mwestphal · August 7, 2020, 3:56pm

alongside your .vtm file, there is a folder named domain_00000080, share it please.

Victor · August 7, 2020, 3:59pm

Oh you are right! These files below are the ones inside the folder domain_00000080.

mwestphal · August 7, 2020, 4:03pm

please share an archive containing all your files together for simple access, thanks.

Victor · August 7, 2020, 4:08pm

Sorry, I will compress it.

Victor · August 7, 2020, 4:09pm

The file is too large so I uploaded it here.

mwestphal · August 7, 2020, 4:15pm

So, you dataset indeed contains only the fluid domain. To extract the pressure at the airfoil you would need to share the airfoil geometry as well.

Victor · August 7, 2020, 4:18pm

Okay. You mean this file, right?

30P30N_modified_slat_configF_0p2m_AoA5p5.stl (1.4 MB)

mwestphal · August 7, 2020, 4:23pm

Yes.

Open your .stl file, Apply
Open your .vtm file, Apply
Make sure the .vtm file is highlighted in the pipeline browser
Filters -> ResampleWithDataSet
Click on destination mesh and select the .stl file
Apply
Color by pressure

Victor · August 7, 2020, 4:30pm

Thank you! I followed your steps and I got the same! However, what I was actually looking for was: how could I extract those pressure values to generate a 2D Cp vs X/c distribution?. Is there any option inside Paraview to get those values (as well as their position in x)?

Thank you again Mathieu!

mwestphal · August 10, 2020, 7:46am

Please precise what your are trying to achieve.

TimJim · September 17, 2020, 8:44am

Hi @Victor - regarding the 2D Cp vs X/c distribution once you have your pressure applied to the geometry, did you try the “Plot On Intersection Curves”? (Filters -> Alphabetical -> Plot On Intersection Curves)

Judging from the screenshot above, you could set the plane to Z Normal and select your z-slice locations. I think by default, it will try to plot everything so you can untick all the series you don’t want. You’ll also need to set the x-axis X Array Name to Points_X.

Hope that helps a bit!