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Calculating volume of Phase

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Old   March 3, 2008, 11:50
Default Calculating volume of Phase
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Pavan
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Hi All, Assume that I have a problem with say 3 immiscible liquids with different densities such that liquid 1 is above liquid 2 which in turn is above liquid 3 in a cylindrical domain. The domain has a drain at the bottom from where the liquid (liq 3 to begin with) starts to flow out. After certain amount of flow time, if I were to calculate the mass/vol of say liquid 3 remaining in the domain, how would I calculate it?

I tried to use the report volume integral menu by calculating volume integral of field vairable -- Phases -- volume fraction -- liquid 3. This gives a volume in m3 which I then multiply with the density of liq 3 to get the mass. However, I am not sure this is the correct way to do it because I observed that when I use this procedure to calculate the volume of say liq 2 which is just floating down, the value of the volume changes over the flow time. This should not be the case because liq 2 hasn't been drained yet. It is a const density liq just moving down. I infer then that the vol integral is only providing a sum of volumes of each cell that holds that liq. I am a little confused about how I can calculate the volume that I want. Any ideas? Thanks.

Pavs
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Old   March 3, 2008, 17:49
Default Re: Calculating volume of Phase
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Aidan
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setup a custom field function of Volume Fraction*Phase Density for each of your three phases. Then do a volume integral of the field function. This should give you the mass of each phase in the domain.
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Old   March 5, 2008, 10:04
Default Re: Calculating volume of Phase
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Pavan
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Thanks Aidan. It was pretty much what I was doing. I was concerned about the difference I was seeing over flow time. But the error was less than 1.5% That still should not exist but I guess it could be numerical error or something. I guess I won't worry about it.
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