Hi, Can anyone tell me what
 

Hi,

Can anyone tell me what are the major steps to implement a new boundary condition?

Thanks,

Billy.

Hi Billy, If your new fiel
 

Hi Billy,

If your new field is based on a fixedValueField, you will need to reimplement the operator(==) according to the new condition.
See for instance timeVaryingUniformFixedValueFvPatchField.C
for a good example

If it is a gradient-based conditions you need to implement something similar for the gradient. Look at for instance wallBuoyantPressureFvPatchScalarField.C

Most derived boundary conditions in finiteVolume/fields/fvPatchFields/derivedFvPatchFields
have either fixedGradient or fixedValue as a base class, reading in extra fields as needed.
A good step is to copy one which is closest to what you wish to implement to your personal application-dir and compile it into $FOAM_USER_LIBBIN, keeping it separate from the ones supplied by OpenFOAM.