CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Running, Solving & CFD

What are rhoMin and rhoMax in rhoPimpleFoam?

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   January 9, 2013, 12:31
Default What are rhoMin and rhoMax in rhoPimpleFoam?
  #1
Senior Member
 
immortality's Avatar
 
Ehsan
Join Date: Oct 2012
Location: Iran
Posts: 2,208
Rep Power: 26
immortality is on a distinguished road
in rhoPimpleFoam there are rhoMin and rhoMax what they mean?what are their coefficients?
thaaaaaaaaaaanks!
immortality is offline   Reply With Quote

Old   January 11, 2013, 17:30
Default
  #2
Member
 
Join Date: Jun 2012
Posts: 76
Rep Power: 13
maHein is on a distinguished road
The density in the solver rhoPimpleFoam is limited by the values "rhoMax" and "rhoMin" defined in fvSolutions.
maHein is offline   Reply With Quote

Old   January 12, 2013, 03:34
Default
  #3
Senior Member
 
immortality's Avatar
 
Ehsan
Join Date: Oct 2012
Location: Iran
Posts: 2,208
Rep Power: 26
immortality is on a distinguished road
thanks.how should it be adjusted based on case?
immortality is offline   Reply With Quote

Old   January 15, 2013, 11:43
Default
  #4
Senior Member
 
immortality's Avatar
 
Ehsan
Join Date: Oct 2012
Location: Iran
Posts: 2,208
Rep Power: 26
immortality is on a distinguished road
any idea about setting the rhoMin and rhoMax?
do we should a guess about minimum and maximum f rhos in the problem we solve?or its default should be used?
please give me a guide.
thanks alot.
immortality is offline   Reply With Quote

Old   January 15, 2013, 12:36
Default
  #5
Senior Member
 
mturcios777's Avatar
 
Marco A. Turcios
Join Date: Mar 2009
Location: Vancouver, BC, Canada
Posts: 740
Rep Power: 28
mturcios777 will become famous soon enough
These are values that you set based on your knowledge of the case you are simulating. It is up to you to ensure they are correct. If you look in the pEqn.H file you will see that is the operation done rho = max(rho,rhoMax) and the like.
mturcios777 is offline   Reply With Quote

Old   January 16, 2013, 09:46
Default
  #6
Senior Member
 
immortality's Avatar
 
Ehsan
Join Date: Oct 2012
Location: Iran
Posts: 2,208
Rep Power: 26
immortality is on a distinguished road
im not sure about max and min of rho exactly.can i set it by a factor of safety?then turn the results less exact or just each iteration takes more time?
Thanks.
immortality is offline   Reply With Quote

Old   January 16, 2013, 12:55
Default
  #7
Senior Member
 
mturcios777's Avatar
 
Marco A. Turcios
Join Date: Mar 2009
Location: Vancouver, BC, Canada
Posts: 740
Rep Power: 28
mturcios777 will become famous soon enough
No, all that happens is that after the p is solved for, rho is then limited by the max/min values. All cells where rho is > rhoMax are set to rhoMax, all cells where rho < rhoMin are set to rhoMin.
mturcios777 is offline   Reply With Quote

Old   January 16, 2013, 17:10
Default
  #8
Senior Member
 
immortality's Avatar
 
Ehsan
Join Date: Oct 2012
Location: Iran
Posts: 2,208
Rep Power: 26
immortality is on a distinguished road
excuse me.why it is intended?density is obtained from equation of state,isn't it?if thats true why rho is bounded?and if we acept that it doesn't seem an accurate way.could give me a bit guidance?
immortality is offline   Reply With Quote

Old   January 16, 2013, 17:21
Default
  #9
Senior Member
 
mturcios777's Avatar
 
Marco A. Turcios
Join Date: Mar 2009
Location: Vancouver, BC, Canada
Posts: 740
Rep Power: 28
mturcios777 will become famous soon enough
The bounding is there for your convenience; this is to bound the solution if you want. If you don't want rho to be bounded, just set rhoMin 0 and rhoMax to something absurdly high.
mturcios777 is offline   Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
what is the purpose of rhoMin and rhoMax in fvsolution mihaipruna OpenFOAM Running, Solving & CFD 3 July 2, 2012 09:19


All times are GMT -4. The time now is 21:33.