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

incompressible thermo type (in buoyantSimpleFoam)

Register Blogs Community New Posts Updated Threads Search

Like Tree1Likes
  • 1 Post By Tobi

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   January 19, 2012, 05:31
Default incompressible thermo type (in buoyantSimpleFoam)
  #1
Senior Member
 
Andrea Pasquali
Join Date: Sep 2009
Location: Germany
Posts: 142
Rep Power: 16
andrea.pasquali is on a distinguished road
Hi all,
I'm trying to compile the buoyantSimpleFoam with basicRhoThermo type to use the <incompressible> prop. to run simulation with water liquid (I saw this set up in chtMultiRegionLiquidFoam).
I tested the chtMultiRegionFoam with <incompressible> thermo type for liquid water and it work well, but it is transient. I want steady. So I tryied the chtMultiRegionSimpleFoam with <incompressible> thermo type and it crashes in hEqn because it divide rho/psi where psi = 0 !
If I use the hEqu of buoyantSimpleFoam it works but the temperature field is not solved !
Why the chtMultiRegionSimpleFoam with <incompressible> thermo type does not work? Should it work?
Did anyone meet this problem?
Thanks for any help, Andrea
__________________
Andrea Pasquali
andrea.pasquali is offline   Reply With Quote

Old   January 20, 2012, 11:25
Default
  #2
Senior Member
 
Andrea Pasquali
Join Date: Sep 2009
Location: Germany
Posts: 142
Rep Power: 16
andrea.pasquali is on a distinguished road
Hi,
in the hEqn I changed the term "rho/psi" with "p" (they have same dimensions).
Now it works but I think the T is not well solved.
I attached the same model solved with buoyanPimpleFoam (bottom) and buoyantSimpleFoam modified (top).
Note that for both I'm using basicRhoThermo type <incompressible> and I added porous medium.

Thanks for any suggestion

Andrea
Attached Images
File Type: jpg picture.jpg (101.1 KB, 225 views)
__________________
Andrea Pasquali
andrea.pasquali is offline   Reply With Quote

Old   January 25, 2012, 08:17
Default
  #3
New Member
 
Maria Jaromin
Join Date: Sep 2011
Posts: 2
Rep Power: 0
jaromin is on a distinguished road
Hi Andrea,

You show here results for a case using buoyantPimpleFoam with the basicRhoThermo type <incompressible>. I also tried the same configuration, but convergence is terrible. There may be many reasons for bad convergence of course, but I am wondering if you also faced any convergence problems here. Have you made any changes to buoyantPimpleFoam?

About the buoyantSimpleFoam, the default thermo type is basicPsiThermo. What kind of changes have to be made to run here basicRhoThermo type <incompressible>?

Thanks for any answers.
Maria
jaromin is offline   Reply With Quote

Old   January 25, 2012, 08:49
Default
  #4
Senior Member
 
Andrea Pasquali
Join Date: Sep 2009
Location: Germany
Posts: 142
Rep Power: 16
andrea.pasquali is on a distinguished road
Hi Maria,for pimple I did not find any strange problem. I used incompressible thermo type (check the multiRegionLiquidHeater tutorial).
You are right, for thesimple the default thermo type is the basicPsiThermo type. I changed it in the .C / .H code adding the basicRhoThermo.
But, as you can see from my results, I think this is not enough!
Let me know if you are going on with this,
Andrea
__________________
Andrea Pasquali
andrea.pasquali is offline   Reply With Quote

Old   November 21, 2013, 06:42
Default
  #5
Member
 
Jamal
Join Date: May 2012
Location: Freiburg
Posts: 54
Rep Power: 12
aujamal20 is an unknown quantity at this point
Hello OpenFOAMers,
I am trying to run a multiRegion case using chtMultiRegionFoam solver and using icoPolynomial equationOfState for fluid region and its not working.
I want to use chtMultiRegionFoam with <incompressible> thermo type for fluid region and to use icoPolynomial for temperatur dependent properties. Please let me know how I can do this. I mean where and what modification are required.

Thanks
Asad
aujamal20 is offline   Reply With Quote

Old   November 21, 2013, 06:46
Default
  #6
Super Moderator
 
Tobi's Avatar
 
Tobias Holzmann
Join Date: Oct 2010
Location: Tussenhausen
Posts: 2,708
Blog Entries: 6
Rep Power: 51
Tobi has a spectacular aura aboutTobi has a spectacular aura aboutTobi has a spectacular aura about
Send a message via ICQ to Tobi Send a message via Skype™ to Tobi
Hello Asad,

it should be possible just to use icoPolynomial to set your fluid.
parthigcar likes this.
Tobi is offline   Reply With Quote

Old   November 21, 2013, 08:43
Default
  #7
Member
 
Jamal
Join Date: May 2012
Location: Freiburg
Posts: 54
Rep Power: 12
aujamal20 is an unknown quantity at this point
Helli Tobi,
Thanks for your immediate response. I have been using following thermotype for fluid region

Quote:
type heRhoThermo;
mixture pureMixture;
transport polynomial;
thermo hPolynomial;
equationOfState icoPolynomial;
specie specie;
energy sensibleEnthalpy;
and in the start simulation does not show any error but its just stops after some itterations--> courant number shoots up to several hundreds and simulation stops. I also checked my pressue BC they seemed quite reasonable.
I just cant figure out what is wrong with my case...
aujamal20 is offline   Reply With Quote

Old   November 21, 2013, 08:50
Default 0 folder of my case...
  #8
Member
 
Jamal
Join Date: May 2012
Location: Freiburg
Posts: 54
Rep Power: 12
aujamal20 is an unknown quantity at this point
please find attached a 0 folder of my case and please let me know if there is any problem BCs.
Thanks
Asad
Attached Files
File Type: zip 0.zip (7.5 KB, 41 views)
aujamal20 is offline   Reply With Quote

Old   November 21, 2013, 15:10
Default
  #9
Super Moderator
 
Tobi's Avatar
 
Tobias Holzmann
Join Date: Oct 2010
Location: Tussenhausen
Posts: 2,708
Blog Entries: 6
Rep Power: 51
Tobi has a spectacular aura aboutTobi has a spectacular aura aboutTobi has a spectacular aura about
Send a message via ICQ to Tobi Send a message via Skype™ to Tobi
I can not find any error in U,p and p_rgh.
Well I wanted to simulate a coat store like that one http://www.thermografie-team.de/news...htspeicher.jpg without success.

My problem was the p and p_rgh initialisation.
After a few modification it was posible to solve my problem with steady state conditions but not with transient solver.

Maybe you find any hints in that thread: http://www.cfd-online.com/Forums/ope...watertank.html

especially with the p and p_rgh initialisation
Tobi 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
second order schemes marine OpenFOAM 67 April 11, 2022 18:19
boundary conditions for simpleFoam calculation foam_noob OpenFOAM Running, Solving & CFD 8 July 1, 2015 08:07
Need help with boundary conditions: open to atmosphere Wolle OpenFOAM 2 April 11, 2011 07:32
Pressure instability with rhoSimpleFoam daniel_mills OpenFOAM Running, Solving & CFD 44 February 17, 2011 17:08
Problem with compile the setParabolicInlet ivanyao OpenFOAM Running, Solving & CFD 6 September 5, 2008 20:50


All times are GMT -4. The time now is 20:32.