Combination not allowed
 

Hi

I can not run the analysis because "Combination : pressure boundary - flow split outlet in fluid 1 is not allowed. execution stopped". But I checked the boundaries and everything seems to be ok. What does that mean?

Thanks

Re: Combination not allowed
 

It seems that you have a combination of a pressure boundary and an outlet boundary in your material defined as fluid 1. Star does'nt allow this. I suggest that you use either an inlet boundary in combination with a pressure boundary and set your initial conditions to a desired pressure at your inlet region or try working with two pressure boundaries. Another possibility is that you may have created two separate domains and have given each one of them a different boundary region i.e. a pressure and an outlet. If this is the case you should change your material number. Hope this helps.

Re: Combination not allowed
 

You can have a pressure boundary and an outlet boundary, but the outlet boundary has to fixed-flux, not split. The problem with the pressure + split combination is that it is ill-posed: you have only specified one pressure and no mass-flux, so there's nothing to determine the pressure drop and hence mass flux (or the other way round, depending how you look at it). There are an infinite number of solutions which would have the pressure and flow split which you specified.