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

Diffusion number in chtMultiRegionFoam

Register Blogs Members List Search Today's Posts Mark Forums Read

Like Tree3Likes
  • 3 Post By Heyheymymy

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   October 20, 2015, 11:30
Default Diffusion number in chtMultiRegionFoam
  #1
New Member
 
Adrien
Join Date: Apr 2013
Posts: 2
Rep Power: 0
Heyheymymy is on a distinguished road
Hello OpenFoam Community,

I am using the chtMultiRegionFoam solver to simulate the heat transfer between two solid layers with different materials properties (no fluid).

I have a question concerning the Diffusion number definition and its use to control the time step adjustment in the chtMultiRegionSolver.

Looking at the source file, I found that unlike the Courant number, the Diffusion Number has dimension. It has a length dimension and is defined as DiNum = thermal diffusivity * timeStep / Length

As a consequence, I am a bit confused when trying to give a target value for this number for the adjustTimeStep option.
In the tutorials the maximum value (maxDi) is set to 10. Is this valid for any case ? Does it depends on the mesh size?

Thank you very much for your help regarding this matter,

Adrien
Artur.Ant, Kummi and Bobby02 like this.
Heyheymymy is offline   Reply With Quote

Old   April 17, 2020, 09:37
Default
  #2
Member
 
Arthur
Join Date: Aug 2014
Location: Italy
Posts: 47
Rep Power: 11
Artur.Ant is on a distinguished road
I think it depends on the case.
In laminar simulation (of a small heat sink), considering natural convection I didn't notice any difference in using maxDi=10 or maxDi=60 with maxCo =0.3.
After the same number of iterations the solution in both cases converged to the same result.
Artur.Ant is offline   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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
AMI speed performance danny123 OpenFOAM 21 October 24, 2020 05:13
SigFpe when running ANY application in parallel Pj. OpenFOAM Running, Solving & CFD 3 April 23, 2015 15:53
Cluster ID's not contiguous in compute-nodes domain. ??? Shogan FLUENT 1 May 28, 2014 16:03
What is the influence of Courant number, the diffusion number and the Péclet number.. bilal8700 Main CFD Forum 1 May 4, 2014 04:37
[Commercial meshers] Trimmed cell and embedded refinement mesh conversion issues michele OpenFOAM Meshing & Mesh Conversion 2 July 15, 2005 05:15


All times are GMT -4. The time now is 03:21.