Hello.

Thanks for your interest in reading my question.

The inlet to my domain carries air with some particle. Many BC's are pressure-outlet BC's. I would like to solve to find the concentrations, while pressure-outlet BC, asks to specify the concentrations at these BC's. Do you have any suggestion that how I can solve this problem?

Thanks, Mazyar

The species concentration specified at pressure oulet will used oly if backflow happens.

Thanks for your replies, even when they are used when there is backflow, how can I know the concentrations on the boundaries? That is my uknown of the problem.

Thanks,

2 Options ...

Provide better guess for concentration at oulet based on engineering judgement

or

Extend the outlet so that backflow would not happen and fluent will not use those data.