hi, i am trying to solve a problam of a porous wall in middle of a pipe, my question is : should i define two volumes of the fluid at the two sides of the porous wall and the volume of the porous wall at the middle? or maybe i should define one volume(the pipe volume) as fluid and add the volume of porous wall in the middle, in this case their will be over lap between the volumes. my next question is how should i define the bounds ? please help me i realy need it to work, i will apritiate any idea.

Please check the porous medium model in User Guide. It talks about porous medium as a special part of fluid zone and there is a separate sub-menu for porous zone. If your fluids are different across the porous zone, then you will anyway will use separate fluid names for them. you have to choose a cell zone as porous zone. As far as I know, if you are also interested in what happens at the interface of porous zone and fluid, then you should keep in mind that slip boundary condition for wall should be used. I will strongly suggest though to consult user guide first.

swarup

It sounds like you are describing a porous jump, not a porous zone. This would be used typically to model a thin membrane like a filter or strainer. If so, you would made one fluid zone for the upstream part of you domain and a second fluid zone for the downstream part. The line that separates the two zones would be defined as a porous jump.

thanks for the answers, evan , my porous zone is 3 mm long i dont think you understand me well, i just realize that i should cut the zones with the split function and not with the boolean commands, do i right ? if i do it with the boolean commands i get walls that i have problam to define. i will realy appritiate your answer for this, i am realy not sure. i will tell more about the problam, actualy the porous zone is not over the all area, i actualy have many disks all over the pipe(in a same Z qurdinate). i am sorry that my english is so poor. waiting for your answer.

You should be able to use either the split function of booleans. Whichever way you do it, though, make sure to follow up with a face merge. This should give you interior zones instead of walls.