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Tanjina June 13, 2013 12:31

problem with inlet BC setting
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Hi all.
Currently I am working on a simple geometry with fluent where water will enter from static reservoir into pipe and air will replace the empty place of reservoir. I put pressure inlet. But it didn't give this type of result. Water is coming instead of air. Could anyone suggest me how can I set inlet BC for this type of phenomena?

I tried to put "air", "water" and "mixture" in pressure inlet ( I also tried with velocity inlet), but fluent says "this type of setting is not application for current setting" for air.

oj.bulmer June 14, 2013 11:33

This is a classic case of VOF model. Have a look at tank flushing tutorial:

You need a clear interface between air and water, and Eulerian models (which I suspct you tried) are not suitable for this.


Tanjina June 14, 2013 12:06

1 Attachment(s)
Thanks for your reply. I have used VOF model for this. Can't set the inlet properly. Last night I tried with volume fraction of water liquid in inlet 0.5. After 500 run, result is look like the attached image.

hossein65 June 30, 2013 19:32

you have to patch the water on your reservoir
your problem is transient, so, don't use steady solver
pressure inlet seems OK, but the major issue is that you have to make sure there is no water in your pressure inlet as you want to make the reservoir empty

Tanjina July 1, 2013 14:06

Thanks a lot Hossein. Finally I have solved my this BC problem some days ago and model is given the expected results. I already did exactly what you said in this thread.

Now I am trying to set up an different model. And facing problem with geometry. Should I discuss about it i this thread, or will I start a new thread ? Please let me know.

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