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

Divergence in rhoPimpleDyMFoam

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

Reply
 
LinkBack Thread Tools Display Modes
Old   March 28, 2012, 15:32
Default Divergence in rhoPimpleDyMFoam
  #1
New Member
 
Bernardo Vieira
Join Date: Apr 2011
Location: USA
Posts: 7
Rep Power: 6
bvieira is on a distinguished road
Hello all!

I put together a solver combining rhoPimpleFoam and PimpleDyMFoam to be able to simulate a pitching airfoil by rotating the entire grid.
After being able to compile everything and run a case with no errors, Iím now facing a convergence problem.

I get an error of number of iterations exceeded:

Code:
 --> FOAM FATAL ERROR:
[0] Maximum number of iterations exceeded
[0]
[0]     From function specieThermo<Thermo>::T(scalar f, scalar T0, scalar (specieThermo<Thermo>::*F)(const scalar) const, scalar (specieThermo<Thermo>::*dFdT)(const scalar) const) const
I think my temperature is diverging and then dragging density with it.
My initial conditions are taken from a converged steady-state solution using rhoSimpleFoam.
I tried to play with the under-relaxation factors, as well as the number of inner correctors (nCorrectors), but that doesnít seem to be helping much (runs longer, but still blows up).
Check mesh passes. This grid has also been used in Fluent before.
Also, Iím running with a pretty small timestep, with MaxCo being less than 1.5. I'm currently using 10 subiterations (nOuterCorrectors).

On my solver side, I think everything seems to be working. I have inspected the mesh during rotation, and it seems to be rotating as desired.
Just as a check, I run the same case, without pitching on rhoPimpleFoam, but still transient, and I was getting a similar problem.

Any ideas on what could be going wrong? Any suggestion on more stable schemes perhaps ? Or changes in the relaxations factors?

I'm attaching the fvSolution and the fvSchemes files.
Some of the underrelaxation factors that I've tried are put as comments in the fvSolution file.

I appreciate any inputs.
Attached Files
File Type: txt fvSolution.txt (2.8 KB, 28 views)
File Type: txt fvSchemes.txt (2.1 KB, 23 views)
bvieira is offline   Reply With Quote

Old   July 19, 2012, 02:22
Default
  #2
New Member
 
notyet
Join Date: Jun 2012
Posts: 9
Rep Power: 5
karkar is on a distinguished road
Hi bvieira,

did you manage to track down your problem?

Could you share your rhoPimpleDyMFoam solver? I currently need that as well and I guess I would be wasting time reinventing a wheel you already made round...
karkar is offline   Reply With Quote

Reply

Tags
iterations exceeded, rhopimplefoam, under relaxation factors

Thread Tools
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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
UDF divergence of a vector cris FLUENT 3 September 4, 2014 18:06
Divergence problem for species transport model MY FLUENT 3 January 11, 2014 05:46
Green's theorem or divergence theorem? Hermano Main CFD Forum 0 November 30, 2011 17:11
Quarter Burner mesh with periosic condition SamCanuck FLUENT 2 August 31, 2011 11:34
divergence in MAC Method Maciej Matyka Main CFD Forum 2 December 19, 2000 11:43


All times are GMT -4. The time now is 10:18.