Specifying volume/Mass fraction in Species Transport for problem without inlet

tanjinjack · January 9, 2011, 10:56

Hi,

Strictly a beginner with limited experience in FLUENT. I am trying to model a simple Species Transport problem that does not involve any reactions. It's a humidity problem.

You can imagine it as a box (actual geometry is more complex) with air of a given humidity inside. Few holes are poked at some places and a heat source is introduced inside the box. The aim is to find out how the humidity end up with the heat source being active chasing the water vapour out through those holes, after it reaches equilibrium.

I can't seem to be able to specify my mass fraction or volume fraction for my fluid (air+water vapour). Some readings on the manual and some searches on the forum show that I may consider using patching or the source term. Which is more probable? Source term is a function of time, is it applicable to my problem (I just want to know the end result, not how it changes)?

Also, I am thinking to use 'pressure outlet' for the holes (my outlets) around the box. However, I think there will still be a flow of water vapour into the box at equilibrium. (Or the heat source will just heat away all the water vapour, isn't it?) Any other boundary conditions I can use?

Will appreciate any advices and helps here.
Thanks a lot.

Regards,
-jin jack-

amirmohebbi · October 9, 2011, 04:42

dear all
hi
I am new in fluent
how i can define all of my mesh zone stagnation air
and mass flow inlet another flow like that fuel
then i have to the mixing rate of them
please help me?
thanks for your attention
amir mohebbi

January 9, 2011, 10:56	Specifying volume/Mass fraction in Species Transport for problem without inlet	#1
tanjinjack New Member Join Date: Nov 2010 Posts: 2 Rep Power: 0	Hi, Strictly a beginner with limited experience in FLUENT. I am trying to model a simple Species Transport problem that does not involve any reactions. It's a humidity problem. You can imagine it as a box (actual geometry is more complex) with air of a given humidity inside. Few holes are poked at some places and a heat source is introduced inside the box. The aim is to find out how the humidity end up with the heat source being active chasing the water vapour out through those holes, after it reaches equilibrium. I can't seem to be able to specify my mass fraction or volume fraction for my fluid (air+water vapour). Some readings on the manual and some searches on the forum show that I may consider using patching or the source term. Which is more probable? Source term is a function of time, is it applicable to my problem (I just want to know the end result, not how it changes)? Also, I am thinking to use 'pressure outlet' for the holes (my outlets) around the box. However, I think there will still be a flow of water vapour into the box at equilibrium. (Or the heat source will just heat away all the water vapour, isn't it?) Any other boundary conditions I can use? Will appreciate any advices and helps here. Thanks a lot. Regards, -jin jack-

October 9, 2011, 04:42	problem to define another fluid in mass flow inlet	#2
amirmohebbi New Member amir Join Date: Jan 2011 Posts: 10 Rep Power: 15	dear all hi I am new in fluent how i can define all of my mesh zone stagnation air and mass flow inlet another flow like that fuel then i have to the mixing rate of them please help me? thanks for your attention amir mohebbi

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