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Fluid dynamics - gas flow / bending pipe

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Excuse me , can somebody give me advice?

I have gas flow in bending pipe. and i have some water in bottom of the pipe.
So, if we increase velocity of gas flow, the water begin to move and may be there will be some bubbles.

How should i model this process? i think i need moving mesh, am i right?

and another difficult question - how to model bubbles of water, which are flying away from the surface of moving water in gas flow???

thank you very much! only in this community i get some rational answers =)

2 Replies Last Post 2011年4月9日 GMT-4 06:17
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2011年4月6日 GMT-4 07:33
Hi

the moving mesh ALE for large displacements is most probably the best.

Bubbles means changing topology, difficult with "hard geometry" possible with level set method or variants thereof

But perhaps in between, you can use DG deformed geometry and assume the bubbles are a +/- constant flow on the insude/upperside of the tube. Then you might be able to keep the same topology and still get bubble like flow. But I'm not sure how to implement that idea, in equations ;)

I believe V4 would be more adequate, 3.5 has ore limited DG and parametric geometry approaches

--
Good luck
Ivar
Hi the moving mesh ALE for large displacements is most probably the best. Bubbles means changing topology, difficult with "hard geometry" possible with level set method or variants thereof But perhaps in between, you can use DG deformed geometry and assume the bubbles are a +/- constant flow on the insude/upperside of the tube. Then you might be able to keep the same topology and still get bubble like flow. But I'm not sure how to implement that idea, in equations ;) I believe V4 would be more adequate, 3.5 has ore limited DG and parametric geometry approaches -- Good luck Ivar

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Posted: 1 decade ago 2011年4月9日 GMT-4 06:17
=) Thank you for answer!

i understand that i need "slug flow simulation", but in Comsol model gallery there are no good examples about it.
there are some but rather strange.

=(


=) Thank you for answer! i understand that i need "slug flow simulation", but in Comsol model gallery there are no good examples about it. there are some but rather strange. =(

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