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High velocitiy in vof than expected

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Old   March 11, 2020, 08:23
Smile High velocitiy in vof than expected
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Hello all,

I have come with some unusual questions. I am not sure it is common or not, because I could not find the answer in Google or forums.

So, in the model description, I have multiple inlets and multiple outlets. The inlets are divided in such a way that only one inlet has one type of parameters and all other haves different parameters and all mix flow through multiple outlets.

So, the problem is I find very high velocities than expected?. I expect outlet with a velocity range of 0.01 to 0.02m/s but I got 1988397m/s. I have attached the image for more info.

Any kind of help would be highly appreciated.

Thank you
Raj
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Old   March 11, 2020, 10:23
Default Convergence
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One reason for high velocities could be convergence or the lack of it. Another reason could be the fluid properties, especially density.
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Old   March 11, 2020, 10:57
Post NO Convergence and Different Densities
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Also, the curve got converged till 200 iterations, after that it started to increase. Fluids have densities like 1017 and 1221 kg/m^3 with same viscosity.
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Old   March 11, 2020, 12:37
Default Convergence
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Then it is very clear that the solution does not converge. The reason for non-convergence could be anything from bad mesh to bad numerical setup. To check mesh, try a single phase, turbulent flow. If that works fine, then mesh is good. Then check material properties and operating conditions, particularly gravity direction, reference pressure location, and operating density. These are important only for multiphase case.
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