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2D Model Problem...

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Hi all,
I'm working on a model which is a 2D representation of a solid container in a multiphase-flow section. what I'm trying to model is to study the relation between the contact angle and the ratio of the viscosity of the two different fluid inside the tank. The model is really simple and it's working in 5-20 second but still I'm not sure the whole model is right or not.
The main problem that I have is that when i increase the time of simulation for about 100 Sec what I could see was that some of the fluid inside the tank will disappear which is quite strange and I think it has to do with the boundary condition on the side wall. Interesting thing is that still the flow structure is kind of similar to what we are looking for, the only thing that makes me worry is that something might be wrong with the model and i wouldn't see it and then the whole result that I'm getting might be wrong.
The model that i uploaded here is the one im trying to work on but in case u wanted to run that model you need to increase the mesh size to extra-fine so that it would run without any error.
any help or anything that you think will be helpful for me will be deeply appreciated.


2 Replies Last Post Jan 22, 2013, 12:37 p.m. EST
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Hello Ramin Parhizkar

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Posted: 1 decade ago Jan 22, 2013, 2:30 a.m. EST
Hi,
I have the same problem. I am trying to simulate a half-filled fuel tank under acc. of 1g in x direction and 0.25g in y direction. Fluid behaves as it is expected, however after a while it disappeares slowly. I have deleted all the heat transfer equations, still is dissappears of vaporize.
Hi, I have the same problem. I am trying to simulate a half-filled fuel tank under acc. of 1g in x direction and 0.25g in y direction. Fluid behaves as it is expected, however after a while it disappeares slowly. I have deleted all the heat transfer equations, still is dissappears of vaporize.

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Posted: 1 decade ago Jan 22, 2013, 12:37 p.m. EST
Hi

Similar problem was discussed in this forum some time ago. Try changing "convective term" from "advanced settings" to "conservative" instead of "non-conservative". This has something to do with losing material.

Best regards

Tero Hietanen
Hi Similar problem was discussed in this forum some time ago. Try changing "convective term" from "advanced settings" to "conservative" instead of "non-conservative". This has something to do with losing material. Best regards Tero Hietanen

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