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-   -   multiphase flow model (water+oil) (http://www.cfd-online.com/Forums/flow-3d/118386-multiphase-flow-model-water-oil.html)

haitham May 26, 2013 22:23

multiphase flow model (water+oil)
 
Good day all

I have multiphase flow model with one fluid (oil+water) in gravity separator tank
how can i know the amount or volume of oil mixture in water
for flow 3D:confused:

second question, is there a way to know the oil concentration for example after 100 second from mixture

Thanks

dmilano May 30, 2013 13:57

If you're using the 2-fluid model then the mixture concentration is defined by the fluid fraction. You can then measure the volume of each fluid using a sampling volume.

haitham June 2, 2013 09:39

multiphase flow model (water+oil)
 
thanks a lot for your reply dmilano

Kindly if i define the initial fluid regions with appropriate densities (in model setup - initial)
fluid region 1 : water density 1000
fluid region 2 :oil density 800

and i have the rate of oil inside the water 5% , so how much define the fluid fraction for each fluid and where define it in initial or in boundary conditions?

thanks

dmilano June 3, 2013 10:11

In two fluid problems the density is computed from the fluid fraction, not the other way around. If you define fluid 1 as water and fluid 2 as oil then you just specify the mixture fluid fraction in the initial conditions and at the boundaries. For example, if you had a mixture of 5% oil and 95% water entering at a boundary you would specify a fluid fraction of 0.95 at this location.

haitham June 5, 2013 00:24

Dear dmilano

if i choose two number of fluid then there is no free surface (no out flow) in my case i have a free surface separator tank and the inlet flow is mixture between oil and water.
which the best model must be use
Drift flux
source mass
or
scalars

thanks alot

dmilano June 5, 2013 10:30

Sorry - I didn't realize that there was a free surface. In this case you'll probably want to use the 1 fluid drift flux model and specify the mixture density at the boundaries, initial conditions, and sources.


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