Patching Zones - DISCONTINUITY at Borders
 

Hi everybody :)

My problem is the following. I have two zones (z1 and z2). I patch two different pressure values (p1 and p2) to theese zones using "Solution -> Solution Initialization -> Patch".

I want a discontinous pressure distribution on the border between z1 and z2 :)

But Fluent produces a continous (smeared) transition on the border :mad:

My question is therefor: is there an option for discontinuously patching values to zones? Or is there another way to assign initial conditions to zones?

Thank you, kind regards,
Gergö

I am assuming you correctly patched a discontinuous pressure to two different cell zones. If so, I don't think that is an actual problem. Recall that Fluent is a finite-volume solver with dynamic variables stored at cell centers. Nothing is stored on cell faces. Hence you cannot specify anything at a border between two cell-zones. The face values are computed from the cell values according to the discretization schemes. The only exception is if you have a boundary condition, then the face values are imposed. The transition you are seeing is a plotting problem. But if you think that the discretization schemes are not appropriate for your problem, then you have a much bigger issue to deal with.

Thank You, LuckyTran! :) I forgot the cell centred property of the solver. Only two rows of cells are affected by the transition, so you're absolutely right!