[-mAx-]

Hi, I was wondering if there is a possibility to display the wall shear stress on a wall.
Since the velocity on my wall is 0, I cannot compute any gradient of U for defining the shear stress as: TAU = MU . du/dn
I assume there is a turnaround...
Any idea or experience?
Thanks in advance

[philippose]

Hello Maxime,

A Good Afternoon to you :-)!

There is a utility in OpenFOAM called "wallShearStress".... this utility should be run in your case folder as follows:

> wallShearStress -latestTime <<----- In case you want only the last time step

> wallShearStress -time <time> <<----- For a specific iteration

> wallShearStress <<----- For all time steps

The utility writes a field to each time step called "wallShearStress", which can be directly post-processed in Paraview like you post-process any other field....

Hope this helps :-)!

Enjoy!

Philippose

[-mAx-]

yes I saw this utility just after I posted the thread.
I am working on it.
Thanks for the confirmation

[idrama]

Hello mAx,

the formular tau=mu*dc/dn from did you get that. For my work, I need a three dimension citation of that formular and not tau = mu du/dy.

cheers

[-mAx-]

It comes from the stress tensor, ie a matrix:
http://en.wikipedia.org/wiki/Stress_(mechanics)

[silviliril]

Here is what you need to do:
run the following command in terminal:

simpleFoam -postProcess -func wallShearStress

The simpleFoam can be replaced with whatever solver you are using.