|January 19, 2010, 12:45||
twoPhaseEulerFoam: turbulence on produces instability of drag phase
Join Date: Mar 2009
Location: Brussels, Belgium
Posts: 100Rep Power: 6
I am trying to simulate a turbulent air - solid particle two-phase flow in a vertical pipe using twoPhaseEulerFoam. I added a source term (as in channelFoam) in the Ub (continous phase) equation to sustain the flow for the use of cyclic BC's. Further I use wedge BC's.
When I switch turbulence off, everything works fine, meaning I get reasonable axial velocity profiles for Ua and Ub.
From the above state I switch turbulence on, and the velocity of the drag phase Ua starts developing in a wrong "unsteady shape", see the attached picture.
- fvSolution and fvScheme are taken from the bed tutorial
- ppForces and kinetic theory is switched off
- drag model: SchillerNaumann
- k is calculated using k = 3/2 (I*U)^2
- epsilon is calculated using epsilon = (c_mu^0.75*k^1.5) / l
- The continous phase bulk Re number is 2.3E+4
I am wondering why the drag phase behaves in such a strange way, after switching on the turbulence model....
Do you have any suggestions, what might be the reason for this behaviour? Or did anyone oberserved similar problems?
Thanks in advance,
|October 11, 2013, 10:02||
Join Date: Jun 2012
Posts: 1Rep Power: 0
I've tried to do the same study, i.e. an bubble column, and happened the same problem as you report. Did you found an solution for your problem with the k-e model?
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