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TrII4d March 8, 2012 16:41

Field functions for a specific Region
Hello everybody,

I want to define a field function for only one region (I have 3 Regions: Inlet, Outlet and Cleaner) ...

($Species2MolarConcentration == 0) ? 0 :

I want that, if $Species2MolarConcentration == 0 only in the Region Cleaner then = 0

does it works?

thanks, for help!


abdul099 March 10, 2012 03:49

A field function will always be valid for the whole domain. All you can do is to put different values for different regions / areas / boundaries etc.
You can access single regions by using the RegionIndes, e.g.
$RegionIndex = 0 ? doSomething : doSomethingElse
Put the index of the desired region for the 0. You can get the RegionIndex by just clicking on a region and looking to the properties window (lower left corner)

TrII4d March 12, 2012 06:50

Dear Abdul,

thank for your reply and sorry for my late reply. I'm not sure, but I think your answer can not really help me. My Problem is not to assign the field function to a specific region, it's more to define the field function for a region according to the time.

I think it helps, if I explain what I'm going to do:
In the picture ( you can see the Inlet, the Cleaner and the Outlet. In the velocity Inlet flows a multi-component gas (C4H10 and N2).
What I want: When my C4H10-N2 gas "arrived" in the Cleaner Region, then the Source Term begins to remove the C4H10 components. Not before!

What I have at the moment:
The Source Term starts at the first iteration (but at the beginning, there is no C4H10 in the Cleaner Region) ... so the Temperature grows up (because of the negative bulk flow).

I hope u can image what im trying to do.

Best regards,

p.s. sorry for that bad english :-(

abdul099 March 15, 2012 04:15

Okay, then I misunderstood it. I don't have a solution right now, but I will keep on thinking about it.

TrII4d March 15, 2012 07:12

Okay ... Thanks Abdul!

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