[simucentral]

Hi,

I was trying to simulate the turbulent flat plate problem. kOmegaSST is the model in use. After a run of 5000 iterations, I tried to post process the wallShearStress. However, I was getting only a maximum value and a minimum value when I ran the tutorial as such with the "Include "wallShearStress"".

I tried to sample wallShearStress on the plate patch. I tried the following methods.
1. sampling from paraview - I noticed the values are getting interpolated and the detail I have due to grading in the plate patch is missing due to interpolation.

2. sampling in controlDict - line, sampling type- uniform, face, midpoint (I tried all), everywhere I am getting interpolated result and the detail is missing.

Upon checking the solution folder, I see the wallShearStress file with the bottomWall patch 400 faces and its results. I trust the wallShearStress values are at the centre of these faces. Total number of entries is also 400. So, if I may ask, is there nay way to correctly extract these values and their corresponding x-axis (length along plate) so that I can get a correct plot of wallShearStress along the plate length?
Or, is my understanding wrong?

Dear Sirs, kindly throw some light on this regard.
Thank you so much in advance.

[simucentral]

Thank You all.
It was easier than I thought.
We just have to sample as surface on the required patch with interpolate false flag.
The following snippet was attached to the controlDict and post processed to obtain that without interpolation on the patch at whatever grading we have on the mesh.

functions
{
wallShearOnPatchNoInterpolation
{
type surfaces; // important setting - sampling type surface
libs (sampling);
setFormat gnuplot;
surfaceFormat raw;
interpolationScheme cellPoint;
fields ("wallShearStress");

surfaces
(

walls_interpolated
{
type patch;
patches ( "bottomWall" ); //make sure you provide the name of the patch
interpolate false; //important setting to obtain the wall shear stress without interpolation - exact value on the face.
}

);

}
}


Thank You all once again. Please correct me if I am wrong.