Derived Boundary condition
 

Hi Foamers,
I am using OpenFOAM2.1.1 version. My solver is steady state and i prepared it by modifying "simpleFoam" solver. I am facing problem with boundary condition for the scalar field (lets say T).
The governing equation for the field T as follows:
At the fixed Walls i need to apply zero flux boundary condition. In the above equation "J" is the flux. So i need to apply J.n=0 at fixed walls. I have little experienced in handling "groovyBC". I know how to use groovyBC for grad(T) and grid varying fixed value. But when i solve J.n=0, i am not getting the expressions for grad(T) or grid varying fixed value.
Can anyone help me. Thanks in advance.

Regards
M Mallikarjuna Reddy