Velocity inlet BC problem
 

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??

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?.....

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.

can you send me the mesh file? I'll try to solve it..

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.

You've mail