About surface normal Gradient
 

Hi everyone,
I am fresher to openFoam. Now i am using openFoam 2.1.1 version. For my needs i need to apply zero flux at the walls for a scalar field.
I am doing project on flow of suspensions (fluid and solid particles) through square channels. here i need to give zero flux at walls for the solid particle volume fraction. After applying this boundary condition i got an expression like
dT/dy=f(velocity, T).
where T=particle volume fraction(no units, scalar quantity).
So for my case i need to give surface normal gradient. Please suggest me how to write code for it.


Thanks
Regards
Mallikarjuna