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## bubbly flow: udrift in laminar flow...

Hi,

I am currently working with the bubbly flow application mode in a laminar flow.

The gaz velocity, ug, is computed thanks:
ug=ug+uslip+udrift

In the help, is it said that the drift velocity is computed only in a turbulent flow. However, in the laminar flow, we can see that this dift velocity is non equal to zero. Does anyone know if, from a physical point of view, if this velocity should be equal to zero in a laminar flow?

thanks a lot!

Patrick

PS: in version 3.5, the drift velocity was equal to zero in a laminar flow

1 Reply Last Post Jan 25, 2013, 10:59 AM EST

Hello Patrick Namy

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Posted: 5 years ago
Hi Patrick,

For more information on the bubbly flow physics, please refer to the "Theory for the bubbly flow interface" section in the CFD user guide, or to the following references:

1. A. Sokolichin, G. Eigenberger, and A. Lapin, “Simulations of Buoyancy Driven
Bubbly Flow: Established Simplifications and Open Questions,” AIChE Journal,
vol. 50, no. 1, pp. 24–49, 2004.

2. D. Kuzmin and S. Turek, Efficient Numerical Techniques for Flow Simulation in
Bubble Column Reactors, Institute of Applied Mathematics, University of Dortmund,
2000.

3. D. Kuzmin, S. Turek, and H. Haario, Finite Element Simulation of Turbulent
Bubbly Flows in Gas-liquid Reactors, Ergebnisberichte Angew, Math, 298, University
of Dortmund, 2005.

4. M.P. Schwarz and W.J. Turner, “Applicability of the Standard k-e Turbulence Model
to Gas-stirred Baths,” Applied Mathematical Modelling, vol. 12, pp. 273–279, 1988.

5. C. Crowe, M. Sommerfeld, and Y. Tsuji, Multiphase Flows with Droplets and
Particles, CRC Press, 1998.

Best,
Fabrice

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