
[Sponsors] 
February 18, 2013, 06:46 
interFoam algorithm

#1 
New Member
Pierre HORGUE
Join Date: May 2009
Posts: 26
Rep Power: 10 
Hi ,
For each time step, I found that the order of the computations is a little bit strange. 1) It computes the new surface force term using the alpha field at the time "n" Code:
twoPhaseProperties.correct(); Code:
#include "alphaEqnSubCycle.H" Code:
//  Pressurevelocity PIMPLE corrector loop while (pimple.loop()) { #include "UEqn.H" //  Pressure corrector loop while (pimple.correct()) { #include "pEqn.H" } if (pimple.turbCorr()) { turbulence>correct(); } } It seems more logical to update the surface force term (step 1) just after computing the new alpha field. In my mind, the algorithm should be : 1) update properties time "n" 2) compute implicitly velocitypressure field "n+1" 3) compute alpha field "n+1" using the velocitypressure previously computed Am I wrong ? Thank You, Pierre 

February 19, 2013, 07:20 

#2 
New Member
Pierre HORGUE
Join Date: May 2009
Posts: 26
Rep Power: 10 
I confirm what I said before, this is an error in the "interFoam" solver (and the derivated solvers).
In the H. Rusche thesis, page 162, we can see the following solution procedure : steps 14 : refer to the moving frame step 5 : transport "alpha1" step 6 : update properties (smooth gamma => curvature computation => surface force term) step 7 and 8 : PISOloop to compute pressurevelocity fields. Maybe this error should be reported to the OpenFOAM Foundation to correct it for the following versions. Pierre 

February 19, 2013, 08:51 

#3 
Senior Member
Anton Kidess
Join Date: May 2009
Location: Germany
Posts: 1,225
Rep Power: 23 
How are step 58 different than what is already implemented?
__________________
*On twitter @akidTwit *Spend as much time formulating your questions as you expect people to spend on their answer. 

February 19, 2013, 08:58 

#4 
New Member
Pierre HORGUE
Join Date: May 2009
Posts: 26
Rep Power: 10 
In the current version of "interFoam", the step 6 is computed before the step 5.
First it computes the surface force term : Code:
twoPhaseProperties.correct(); Code:
#include "alphaEqnSubCycle.H" 

February 19, 2013, 10:50 

#5 
Senior Member
Anton Kidess
Join Date: May 2009
Location: Germany
Posts: 1,225
Rep Power: 23 
The interface curvature for the surface force term is calculated by calling interface.correct() after the alphaEqnSubCycle.
__________________
*On twitter @akidTwit *Spend as much time formulating your questions as you expect people to spend on their answer. 

February 19, 2013, 11:03 

#6 
New Member
Pierre HORGUE
Join Date: May 2009
Posts: 26
Rep Power: 10 
Ok, I had inverted the "correct" function of twoPhaseMixture for the viscosity with the "correct" function of interfaceProperties for the curvature.
Thank you for your reply 

Thread Tools  
Display Modes  


Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
interFoam vs. simpleFoam channel flow comparison  DanM  OpenFOAM Running, Solving & CFD  11  January 5, 2013 07:21 
Does PISO algorithm work with interfoam in openFOAM 2.1.0?  Krishna Sandeep  OpenFOAM Running, Solving & CFD  3  June 14, 2012 01:32 
Open Channel Flow using InterFoam type solver  sxhdhi  OpenFOAM Running, Solving & CFD  3  May 5, 2009 21:58 
About Phase Coupled SIMPLE (PCSIMPLE) algorithm  Yan Kai  Main CFD Forum  0  April 18, 2007 03:48 
About Phase Coupled SIMPLE (PCSIMPLE) algorithm  Yan Kai  FLUENT  0  April 13, 2007 23:17 