BC in multiphase flow

Gerim55 · July 23, 2013, 03:08

Hi everyone!

I am engaged in studing of sewage aeration (multiphase flow water/air, Eulerian - Eulerian approach).
Could you help me with BC?

How can I specify BC, where it will be like water surface (water - primary phase), but for air it will be outlet (or air will vanish there) ?

oj.bulmer · July 24, 2013, 04:22

What you are probably looking for is a degassing boundary condition that works as a mass sink for the air but a free slip wall for water.

CFX has an in-built degassing BC but FLUENT didn't untill version 14.5 (I guess). If you have FLUENT 14.5, look for this BC in your simulation.

Otherwise, you may have to write a UDF to achieve this.

OJ

Gerim55 · July 24, 2013, 05:53

thanks for the reply! I've really worked in Fluent 14.0 and that's why I've not seen BC that you mentioned.

July 23, 2013, 03:08	BC in multiphase flow	#1
Gerim55 New Member Ivan Telnov Join Date: Dec 2011 Posts: 15 Rep Power: 14	Hi everyone! I am engaged in studing of sewage aeration (multiphase flow water/air, Eulerian - Eulerian approach). Could you help me with BC? How can I specify BC, where it will be like water surface (water - primary phase), but for air it will be outlet (or air will vanish there) ?

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July 24, 2013, 04:22		#2
oj.bulmer Senior Member OJ Join Date: Apr 2012 Location: United Kindom Posts: 473 Rep Power: 20	What you are probably looking for is a degassing boundary condition that works as a mass sink for the air but a free slip wall for water. CFX has an in-built degassing BC but FLUENT didn't untill version 14.5 (I guess). If you have FLUENT 14.5, look for this BC in your simulation. Otherwise, you may have to write a UDF to achieve this. OJ

July 24, 2013, 05:53		#3
Gerim55 New Member Ivan Telnov Join Date: Dec 2011 Posts: 15 Rep Power: 14	thanks for the reply! I've really worked in Fluent 14.0 and that's why I've not seen BC that you mentioned.