3D multiphase micro model: mixing effect of air and water at the T junction

ehsanfareed · November 25, 2009, 06:49

Hi All,
I have a T shape (3D) micro channel, from the left air enters and from below water enters (both are velocity inlets), the flow is laminar, time unsteady, VOF model. I want to see the mixing effect of air and water at the T junction. It is supposed to be a bubble formation at the junction and the bubble is then carried away with the air flow to the outlet (pressure outlet).

But what I get is that water level starts to rise in the channel and there is no mixing effect or bubble formation, I get a clear phase boundary between air and water, you can see the picture.
http://yfrog.com/ek61388547j

I dont know what is the problem, Also I want to use PTFE as a wall material to see its effect on the water as it is a hydrophobic material, but I am unable to define a User Define Material Database for PTFE. Also I want to know that which property of PTFE should be given which defines its hydrophobic character.

Please help me in the above 2 problems I am having regarding the mixing effect and the PTFE material, I shall be thankful to you.

Regards,
Ehsan Fareed

ehsanfareed · November 30, 2009, 14:56

C'mon anyone....................????

ashish.nitame · March 22, 2015, 23:29

hello,

did you reach to any solution because even I am stuck with the same problem of "no buuble formation" (stratified flow).

November 25, 2009, 06:49	3D multiphase micro model: mixing effect of air and water at the T junction	#1
ehsanfareed New Member Ehsan Fareed Join Date: Nov 2009 Location: Magdeburg, Germany Posts: 3 Rep Power: 17	Hi All, I have a T shape (3D) micro channel, from the left air enters and from below water enters (both are velocity inlets), the flow is laminar, time unsteady, VOF model. I want to see the mixing effect of air and water at the T junction. It is supposed to be a bubble formation at the junction and the bubble is then carried away with the air flow to the outlet (pressure outlet). But what I get is that water level starts to rise in the channel and there is no mixing effect or bubble formation, I get a clear phase boundary between air and water, you can see the picture. http://yfrog.com/ek61388547j I dont know what is the problem, Also I want to use PTFE as a wall material to see its effect on the water as it is a hydrophobic material, but I am unable to define a User Define Material Database for PTFE. Also I want to know that which property of PTFE should be given which defines its hydrophobic character. Please help me in the above 2 problems I am having regarding the mixing effect and the PTFE material, I shall be thankful to you. Regards, Ehsan Fareed

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November 30, 2009, 14:56		#2
ehsanfareed New Member Ehsan Fareed Join Date: Nov 2009 Location: Magdeburg, Germany Posts: 3 Rep Power: 17	C'mon anyone....................????

March 22, 2015, 23:29		#3
ashish.nitame New Member Ash Join Date: Dec 2014 Posts: 1 Rep Power: 0	hello, did you reach to any solution because even I am stuck with the same problem of "no buuble formation" (stratified flow).