Right solve or not, if during all iterations Ansys CFX Solver manager writes, that he set up artifical wall on the outlet (in my case) ? Howewer, all residuals has attained the level required and mass flow rate at the inlet equal to the mass flow rate at the outlet.
The CFX solver puts an artificial wall if the flow doesn't fill the whole area of the boundary condition. It is a default setting in CFX to keep the residuals low (you can turn it off in expert parameters options, but it is not recommended). The quality of your solution highly depends on the "dimension" of the artificial wall. The situation differs, whether it is 0.5% or 50%. There is no general rule for how much is acceptable; however, you should avoid it if you can (for instance it can lead to falsely overestimated static pressure near the outlet). From my experience, I can tell that an artificial outlet wall happens because the flow is not fully developed, and your domain is just too short to model it fully. Try to move the boundary condition from the field you investigate, and the problem shouldn't occur.
The CFX solver puts an artificial wall if the flow doesn't fill the whole area of the boundary condition. It is a default setting in CFX to keep the residuals low (you can turn it off in expert parameters options, but it is not recommended). The quality of your solution highly depends on the "dimension" of the artificial wall. The situation differs, whether it is 0.5% or 50%. There is no general rule for how much is acceptable; however, you should avoid it if you can (for instance it can lead to falsely overestimated static pressure near the outlet). From my experience, I can tell that an artificial outlet wall happens because the flow is not fully developed, and your domain is just too short to model it fully. Try to move the boundary condition from the field you investigate, and the problem shouldn't occur.
Sometimes the artificial wall is used to help the solution and will be phased out as the solution gets more stable. If it remains a problem at the end of your solution run consider modelling the outlet as an opening rather than as an outlet. An opening will allow flow to enter aswell as leave in a physical way based on the pressure boundary condition set at the opening.
It is not a 100% yes or no.
The artificial wall is a numerical approach to avoid the backflow in an outlet boundary condition. In an outlet boundary condition it is assumed nothing can to flow in. During the iterations this assures that the mass flow will be respect - the imbalance must to be next or equal zero. It is expected that after some iterations the flow is stable and flowing out from the domain.
If the artificial wall does not vanish or has a big fraction of the outlet area e.g. 90%. Your boundary is not an outlet or the position of the outlet was ill-chosen. The domain has some re-circulation or reattachment zone in the position of the outlet. And the boundary or the domain must be re-thought changing the position or the boundary condition type e.g. opening as CFX advices in the solver report
Mathematically a solution was found, but it can have no physical meaning.
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