two separated liquid "phases/flows"

BillT · December 18, 2018, 05:08

Hi,
I am trying to model a flow of 2 liquids (both water) through a channel filled with air. I want them to spread in different directions (see below), which I tried by defining different momentum source terms. In my simulation the two water phases always mix up and flow downwards only (just the y-direction). I set up the eulerian multiphase model with 3 eulerian phases (air, water1, water2). At my inlet I set the volume fractions of both water phases to 0.5 and the same velocity. Do I have to set any phase interactions I forgot or use the discrete phase model to get a result as shown below?

Thank you in advance!

LuckyTran · December 18, 2018, 07:33

The water|water part is not a multi-phase problem. This part alone (ignoring the air) you could solve using the species transport model, not the multi-phase model. You might even be able to simulate this using a passive scalar approach to track the different waters. This is an odd setup.

What are your boundary conditions? And what drives the flow? Is gravity enabled or what? I just can't follow the setup.

BillT · December 19, 2018, 06:40

Hey,
sorry for my late response. Thank you for your advise with the species transport model. I will have a look.

My boundary conditions:

I have one inlet zone at the top with both water phases flowing into my channel equally (volume fraction = 0.5) and a velocity of 0.01 m/s.

The bottom of my channel is a presure outlet. The rest is wall.

I want to model the flow over two inclined planes and flow is driven through gravity (like in the picture). Because the x-component of the gravity is different for both planes i try to model this a source term.

My two water phases just dont split up.

December 18, 2018, 05:08	two separated liquid "phases/flows"	#1
BillT New Member Join Date: Oct 2018 Posts: 3 Rep Power: 7	Hi, I am trying to model a flow of 2 liquids (both water) through a channel filled with air. I want them to spread in different directions (see below), which I tried by defining different momentum source terms. In my simulation the two water phases always mix up and flow downwards only (just the y-direction). I set up the eulerian multiphase model with 3 eulerian phases (air, water1, water2). At my inlet I set the volume fractions of both water phases to 0.5 and the same velocity. Do I have to set any phase interactions I forgot or use the discrete phase model to get a result as shown below? Thank you in advance!

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December 18, 2018, 07:33		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,676 Rep Power: 66	The water\|water part is not a multi-phase problem. This part alone (ignoring the air) you could solve using the species transport model, not the multi-phase model. You might even be able to simulate this using a passive scalar approach to track the different waters. This is an odd setup. What are your boundary conditions? And what drives the flow? Is gravity enabled or what? I just can't follow the setup.

December 19, 2018, 06:40		#3
BillT New Member Join Date: Oct 2018 Posts: 3 Rep Power: 7	Hey, sorry for my late response. Thank you for your advise with the species transport model. I will have a look. My boundary conditions: I have one inlet zone at the top with both water phases flowing into my channel equally (volume fraction = 0.5) and a velocity of 0.01 m/s. The bottom of my channel is a presure outlet. The rest is wall. I want to model the flow over two inclined planes and flow is driven through gravity (like in the picture). Because the x-component of the gravity is different for both planes i try to model this a source term. My two water phases just dont split up.