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Old   October 14, 2009, 09:52
Default Velocity inlet BC problem
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Felipe Gutiérrez Donoso
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I have a 5" plate orifice device in a pipe system. The calculated speed at the inlet is 0.61 m/s (20" inlet), that corresponds to 120 lt/s.

I run the calculation and the resulting mean velocity in the orifice is 3.2 m/s, something diferent to the 9.2 resulting from dividing Flow/area.

The fluid is incompresible, any suggestion about it??
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Old   October 15, 2009, 02:07
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Svetlin Philipov
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Post the whole situation..... what is the BC at the other end? what kind of turbulent model you use? what is the mean velocity after initialization?.....
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Old   October 15, 2009, 08:06
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I´m using velocity inlet BC (0.61 m/s) and Pressure outlet BC at the other end (Atmospheric, 0 Pa). The turbulence model is k-epsilon with standard wall treatment. The initialisation is 0.61 m/s, calculating from the inlet.

The mean velocity at the inlet is 0.61 m/s in a developed flow section, and into the plate orifice is 5.1 m/s, the calculated velocity there must be 15 m/s according to flow/area on an incompresible flow.

The residuals are 10e-5 and it seems to have a good convergence.

Thanks for reading Philipov.
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Old   October 15, 2009, 09:47
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can you send me the mesh file? I'll try to solve it..
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Old   October 15, 2009, 13:34
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Where can I send you the files?? mi e-mail is figd84@gmail.com i´ve sent you an e-mail through this forum, don´t know if you get it.
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Old   October 16, 2009, 01:46
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