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Patrice Jaumouillie September 14, 2001 14:13

ASM/Homogeneous
 
Hello everybody.

Is it possible to use the Algebraic Slip Model with the homogeneous multiphase model ?

I have to study a three phase flow (solid in sewers !) with a free surface. I have a continuous gaz phase for air, a continuous liquid phase for water and a solid dispersed phase for the particles (i know the settling velocities of the particles).

What is the best way to modelise this problem (IPSA ?)

Thank you.

Michael Rasmussen September 17, 2001 04:19

Re: ASM/Homogeneous
 
Hi Patrice

As far as I remember, the homogeneous model assumes an average density and only solves the bulk momentum and continuity equation (allthough keeping track of the different volume fractions). What I assume is your problem is that the gravity should seperate the air, solid and water. For that reason you cannot get the the solid to seperatate and the air to escape the water - unless they are so in the initial condition. You need to use the multi-fluid model in order to get proper seperation. Using the inter-phase friction term, modelled through the Fortran routines, you can get the right settling velocity. (BTW the surface sharpening algorithm used in the homogeneous does not work for the multi-fluid model)

Maybe my knowledge is outdated on this ?

Best regards Michael



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