Can we give two different species as input in fluent..for example there are two ducts.. i want to give air(water+oxygen+nitrogen) as input to one duct and a gas like butane through the second duct...there is no interaction between these two.. i mean its not a butane_air mixture that is sent but the species themselves are seperately fed... is it possible to give an input like this...

Yes, this is possible you have to: -activate species transport; -define your mixture (water+oxygen+nitrogen+ butane)in materials panel; -put mass fraction values in inlet sections(e.g. velocity inlet BC).

Giordano Bruno

i alreadu tried in that way as i felt it is the only way to define ... but on doing that.. fluent is solving for all the species in both the ducts.. that is,, it solves for all the 3 species in both ducts and 1-sumof mass fractions is the fourth species. But for me in one duct only one gas is present.. it should not solve for nitrogen and oxygen in that duct,,, even though i give the species which are not reqds as zero... it still solveing for the other species and 1-sum of the solved species is taken in nitrogen which is not present in the duct...