Slip BC not working properly
 

Running the cavity case with icoFoam, I changed the boundary condition for the fixedWalls patch from fixedValue to slip, changing also the boundary file from wall to patch. I did this in order to test the slip BC in a simple case.

The result was not what I had expected. The side walls defined as slip walls, when visualized with paraFoam, show velocity in the X direction (normal to the patch). This should not happen acording to the definition of the condition "slip" given by OpenFOAM.

"Slip: zeroGradient if http://www.openfoam.com/docs/user/img/user450x.png is a scalar; if http://www.openfoam.com/docs/user/img/user451x.png is a vector, normal component is fixedValue zero, tangential components are zeroGradient"


Has anyone else had problems with this condition? Is it an OpenFOAM bug, or am I just missunderstanding what slip BC should do? Maybe I am missing some additional setting in order to make slip condition work.


Pressure condition is zeroGradient as in the original icoFoam/cavity case.



Thank you.

Also p, k and epsilon are slip.
You can check the motorbike tutorial.

regards

Andrea

slip boundary condition
 

Recently ,i do a lot of subjects on 'slip boundary condition',
some theoretically work have done, next step is how to implement in a soft ,which could deal with slip boundary conditon ,
thank you for your sharing that successful case!
thank you !

ParaFOAM
 

This is simply a paraFoam artifact. Change the rendering mode and you will see those X velocities disappear.