Volume fraction for entire domain in interFoam

jmcneill · May 21, 2012, 09:49

All,
I'm trying to determine the total phase-1 volume fraction at each time step of a simulation to calculate the mass of phase-1 in the domain. I've tried a few methods with swak4foam and Paraview, but I'm not confident in the numbers I am seeing. I noticed that the value I want is written to the log file at each time step as "Phase-1 volume fraction =". Is there a simple way to write this value to a separate output file? Thanks in advance.

Phicau · May 21, 2012, 10:32

Hi

just type on a terminal if your log file is named "log":

Code:

cat log | grep Liquid | cut -d' ' -f6 > massLog

and you will get a file called massLog with the mass evolution.

jmcneill · May 21, 2012, 11:20

Grep is an interesting thought. Thanks for that. I haven't used grep before, but is there a way to write the time in addition to alpha1? I eventually want to be able to plot alpha1 vs time.

Phicau · May 21, 2012, 11:26

I think it would be fairly easy to write a python script to do that. Just take into account that you have several mass values each time.

gschaider · May 21, 2012, 18:59

Quote:

Originally Posted by jmcneill

Grep is an interesting thought. Thanks for that. I haven't used grep before, but is there a way to write the time in addition to alpha1? I eventually want to be able to plot alpha1 vs time.

Quote:

Originally Posted by Phicau

I think it would be fairly easy to write a python script to do that. Just take into account that you have several mass values each time.

Extracting values from a log and plotting them can be easily (that's what I think) done with http://openfoamwiki.net/index.php/Co...omRegexp-files

Bernhard · May 22, 2012, 03:10

Alternatively, you can use volumeIntegrate from the simpleFunctionObjects (see contribution by Bernhard Gschaider)
http://openfoamwiki.net/index.php/Co...unctionObjects

Advantage here is that you don't need an extra step if you put it in the controlDict.

May 21, 2012, 09:49	Volume fraction for entire domain in interFoam	#1
jmcneill New Member James McNeill Join Date: Feb 2012 Posts: 4 Rep Power: 14	All, I'm trying to determine the total phase-1 volume fraction at each time step of a simulation to calculate the mass of phase-1 in the domain. I've tried a few methods with swak4foam and Paraview, but I'm not confident in the numbers I am seeing. I noticed that the value I want is written to the log file at each time step as "Phase-1 volume fraction =". Is there a simple way to write this value to a separate output file? Thanks in advance.

May 21, 2012, 10:32		#2
Phicau Senior Member Pablo Higuera Join Date: Jan 2011 Location: Auckland Posts: 627 Rep Power: 19	Hi just type on a terminal if your log file is named "log": Code: cat log \| grep Liquid \| cut -d' ' -f6 > massLog and you will get a file called massLog with the mass evolution.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
volume fraction in mixture model and VOF????	multiphase-flow	FLUENT	4	August 7, 2014 11:35
Mass fraction and volume fraction	eric weddle	CFX	0	September 26, 2011 06:02
Difference between Volume Fraction and Mass Fraction in CEL	foo7	CFX	0	September 21, 2011 09:45
On the damBreak4phaseFine cases	paean	OpenFOAM Running, Solving & CFD	0	November 14, 2008 22:14
Differences between serial and parallel runs	carsten	OpenFOAM Bugs	11	September 12, 2008 12:16

May 21, 2012, 11:20		#3
jmcneill New Member James McNeill Join Date: Feb 2012 Posts: 4 Rep Power: 14	Grep is an interesting thought. Thanks for that. I haven't used grep before, but is there a way to write the time in addition to alpha1? I eventually want to be able to plot alpha1 vs time.

May 21, 2012, 11:26		#4
Phicau Senior Member Pablo Higuera Join Date: Jan 2011 Location: Auckland Posts: 627 Rep Power: 19	I think it would be fairly easy to write a python script to do that. Just take into account that you have several mass values each time.

May 22, 2012, 03:10		#6
Bernhard Senior Member Bernhard Join Date: Sep 2009 Location: Delft Posts: 790 Rep Power: 22	Alternatively, you can use volumeIntegrate from the simpleFunctionObjects (see contribution by Bernhard Gschaider) http://openfoamwiki.net/index.php/Co...unctionObjects Advantage here is that you don't need an extra step if you put it in the controlDict.