Crate the mesh with blockMesh and then convert into the fluent format.

With blockMesh it is easy to create partitions.

Franco

Thanks for your kind reply Dr Franco Concli.... can you please explain a little bit more ?

Dear Muhammad Furqan Ali,

If the only concern is grid focusing, I do not think there is a need to define a separate INNER ZONE. In GAMBIT, if you use only ONE EDGE shared between two faces (both faces being meshed), then there is no need to assign any boundary condition to that edge. 

I still don't understand the need for assigning a separate zone....the entire domain can be assigned as a single fluid continuum with the x-mesh being refined near the inlet (as per your requirement).

I hope you are using VOF...which simulates the problem based on a single-fluid formulation.

I hope this helps.

Best regards.

Shaswat Saincher 

Hi, 

Luckily, I solved the above problem in Gambit software.. In this 2D problem I found Gambit is more responsive than ICEM..

I made three connected faces cut by two straight edges. In boundary condition dialog box , these two straight edges assigned as interior. Finally, important task is done is zone dialog box, Middle one is assigned as inner zone and other two are outer zones... Hence, bubbles do not affect by interior straight edges and can pass-through easily. Now, different source term can be apply in middle zone separately.

Regards,

M. F. Ali

Dear Muhammad Furqan Ali,

Like I said, edges with mesh on either side do not necessitate any boundary conditions in GAMBIT...the mesh (and therefore domain) is considered continuous through such edges by the solver.

However, I haven't carried out "serious" FW-H (acoustic) simulations in FLUENT....hence have never used the "interior" boundary condition before. 

Nonetheless, it was nice to learn application of a new boundary condition from you!

Thanks and best regards.

Shaswat Saincher