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Bubble size for eulerian model

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Old   April 28, 2010, 01:49
Default Bubble size for eulerian model
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karine
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Hi dear colleagues,
i am using Fluent to simulate a vertical separator.

In the bottom part of the separator, i have liquid as continuous phase with a free vortex on the interface, and some bubbles (not a lot)
In the upper part, i have gas as continuous phase with some liquid droplets
(not a lot also)

I cant use VOF because the phases are not clearly separated (bubbles and liquid droplets near the interface). I tried it and the results are very bad.

So, for simulating it in Fluent, i need to use an eulerian model. The problem is that the model needs a particle size for bubbles (or droplets) to calculate drag, and the results will depends on this size.
As i dont have any reprsentattive bubble size (or droplet size) in my flow, how must i choose this dimension???

Thanks a lot for ure help
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Old   April 28, 2010, 12:09
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Ling
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My colleague had the exact problem before. He looked for my suggestion since I was working on boiling, supposed to be knowing bubbles. However I could not answer his question.
I'd suggest to do some literature review

Quote:
Originally Posted by thecfduser View Post
Hi dear colleagues,
i am using Fluent to simulate a vertical separator.

In the bottom part of the separator, i have liquid as continuous phase with a free vortex on the interface, and some bubbles (not a lot)
In the upper part, i have gas as continuous phase with some liquid droplets
(not a lot also)

I cant use VOF because the phases are not clearly separated (bubbles and liquid droplets near the interface). I tried it and the results are very bad.

So, for simulating it in Fluent, i need to use an eulerian model. The problem is that the model needs a particle size for bubbles (or droplets) to calculate drag, and the results will depends on this size.
As i dont have any reprsentattive bubble size (or droplet size) in my flow, how must i choose this dimension???

Thanks a lot for ure help
nstar is offline   Reply With Quote

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