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Torsaki July 30, 2002 23:44

Volume fraction to mass fraction
hi, all friend I have the value of volume fraction in my result and i want to change the volume fraction to mass fraction or concentration. How i do?


Robin July 31, 2002 10:37

Re: Volume fraction to mass fraction
Hi Torsaki,

Look to the units for the answer...

To get the mass fraction, multiply by the density ratio of the two materials:


You can use a similar method to convert to concentration.


New User August 6, 2002 00:36

Re: Volume fraction to mass fraction
Hi all,
If i have volume fraction and i want to cover to concentrition how can i do?Thanknew user

hamza August 13, 2002 16:01

Solution Method in CFX 5.5.1
hi any one,

I want to know as soon as possible what the Alogarethim solution method use in the CFX 5.5.1 is it SIMPLE method or another method?

Robin August 14, 2002 08:56

Re: Solution Method in CFX 5.5.1
Hi Hamza,

Simply put, CFX-5 uses a coupled multigrid approach whereby the hydrodynamic equations (u,v,w,p) are solved simultaneously in a single matrix at each timestep.

For a more thorough explanation, see, or contact CFX.

Regards, Robin

msohail December 25, 2010 01:35

mass fraction to (%vol/vol)
HI all
I am totally lost in the conversion .I need to convert mass fraction to (vol/vol)%. I ahve two gases 0.316 of FReon and 0.684 of Nitrogen.

ghorrocks December 25, 2010 05:12

You use the gas densities to convert mass fraction to volume fraction, as described above.

mitchOlson August 19, 2011 11:23

It looks like I was having the same problem to convert from mass fraction to volume fraction. Here is the formula:


where, vf1=phase 1 volume fraction
vf2=phase 2 volume fraction
wf1=phase 1 mass fraction
wf2=phase 2 mass fraction
rho1=phase 1 density
rho2=phase 2 density

PS. To double check you correctly entered the formula check that vf1 + vf2 = 1

msohail August 21, 2011 00:40

Thanks a lot for your answere . I apreciate it

mamalili February 21, 2015 11:46

I tank U too, deer Olsan

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