[streamline90]

Dear Foamers,

I am running a steady state simulation using the turbulence model k-omega SST and the solver simpleFoam.
The simulation is running well but the results of interest seems underestimated with respect to the experimental data. Since the results of interest are forces and moments exerted on a component ( a pantograph ) on the roof of a train I think I need to better describe the boundary layer development. Therefore I've noticed in certain areas that my yPlus was way too large. As the train is quite long (more than 200 meters) it would be inefficient and resource consuming to just refine all the train roof.
My strategy then would be to refine only the problematic zones of the roof BEFORE the pantograph, adding finer layers.

Having said that, is there a way in openFoam to isolate cell/faces (in this case cells) with a value of yplus (or other quantities) within a certain range (or above/below a certain value ) and then visualize them paraView? (maybe in VTK format..?)

Thanks to anyone who intends to help me solve this problem allowing me to proceed with my dissertation!

Cheers,

Luca

[pbalz]

Hi Luca,

I don't know which OpenFoam version you are using but I guess it's OF4.1 or OF5. For this case you could use the postProcessing utility directly from openfoam:

simpleFoam -postProcess -latestTime -func yPlus

This writes the yPlus values for the boundary patches. Load all solution files in paraview:

paraFoam

and then use the threshold filter for the yPlus values.

[streamline90]

Thanks a lot Pascal, that seems a good idea and in other websites too it seems the only one!
Have a great day,

Luca

[bineet_aero]

Originally Posted by pbalz

Hi Luca,

I don't know which OpenFoam version you are using but I guess it's OF4.1 or OF5. For this case you could use the postProcessing utility directly from openfoam:

simpleFoam -postProcess -latestTime -func yPlus

This writes the yPlus values for the boundary patches. Load all solution files in paraview:

paraFoam

and then use the threshold filter for the yPlus values.

Thanks a lot. Will it be possible to use this utility to find Y+ for solid walls in contact with fluid in conjugate heat transfer problems (for the mappedWalls) ?for example chtMultiRegionSimpleFoam cases etc ?

thanks