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How to define a mixture of two miscible liquids at the inlet?

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Hello,

I have a question about how to define a mixture of two miscible liquids (for instance water and ethanol) at the inlet.

My 2D geometry is as follows: I have two parallel rectangles (representing a channel through which liquid flows) and the two parallel rectangles are connected by a narrow third rectangle so that they are interconnected and it looks like the capital letter i.

The liquids flowing in the upper and bottem parallel rectangle are immiscible (for instance heptane at the top and water at the bottem) and I want to model the interface where these two liquids meet (in the third rectangle which interconnecteds the upper and bottem channel). To do this I use the "Two-Phase Flow, Phase Field" model from the physics tree.

The problem however is that I do not want to define a pure liquid at one of the two inlets (for instance not just water), but I want to define a mixture of two liquids (ethanol and water for instance) so that a part of the ethanol for example disolves into the other liquid (heptane) and you have some kind of extraction and how it affects the liquid-liquid interface.

Does anyone has some hints on how to do this?

Jonas

4 Replies Last Post Apr 19, 2015, 2:08 p.m. EDT
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Hello Jonas Hereijgers

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Posted: 1 decade ago Jan 7, 2014, 11:15 a.m. EST
I think what you are looking for is "Laminar Two-Phase Flow... > Inlet > Volume fraction of fluid 2". Here you can set what percentage of the inlet fluid is fluid 1, for example 0.3 for 30%.


Hope this helps,
Kevin
I think what you are looking for is "Laminar Two-Phase Flow... > Inlet > Volume fraction of fluid 2". Here you can set what percentage of the inlet fluid is fluid 1, for example 0.3 for 30%. Hope this helps, Kevin

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Posted: 1 decade ago Mar 17, 2014, 1:13 p.m. EDT
Hi Jonas,

I have the same problem, did you succeeded to define this three types of fluids?

waiting for your answer,
Anna
Hi Jonas, I have the same problem, did you succeeded to define this three types of fluids? waiting for your answer, Anna

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Posted: 1 decade ago Mar 18, 2014, 4:57 a.m. EDT
Hi Anna,

No I did not find a solution and I gave up on this simulation. Even if it would be possible I am afraid the simulation will take a very long time as a lot of parameters such as viscosity and density are now dependent on the concentration.

If you do find a solution I would be very happy if you would share it with me.

Kind regards and good luck

Jonas
Hi Anna, No I did not find a solution and I gave up on this simulation. Even if it would be possible I am afraid the simulation will take a very long time as a lot of parameters such as viscosity and density are now dependent on the concentration. If you do find a solution I would be very happy if you would share it with me. Kind regards and good luck Jonas

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Posted: 10 years ago Apr 19, 2015, 2:08 p.m. EDT
hi
I want to couple mixture model with structural. But in mixture model I can't define the loading or displacement induced by structural model. can anyone help me?
regards
hi I want to couple mixture model with structural. But in mixture model I can't define the loading or displacement induced by structural model. can anyone help me? regards

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