Problem with validation of regionCouple solver

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

May 22, 2014, 18:09
Problem with validation of regionCouple solver
#1
Member

Join Date: Aug 2013
Posts: 35
Rep Power: 5
I am working on a solver for Stefan problems - i.e. a sharp interface (typically moving) separating two different regions. I started with conjugateHeatFoam from foam-extend-3.0. I solve a Laplace equation for the pressure in two regions with different permeability and then solve for a concentration field (convection-diffusion) in the inner region. Solver is attached (stefanFoam.tar.gz).

In the test problem the interface between the regions has a cosine profile x=1+A*cos(2*pi*y) with -0.5<y<0.5, with A constant. For clarity I choose both perms to be unity so that on the boundary between the domains the pressure should be simply -x if the pressure at the inlet is zero and the pressure gradient at the outlet is -1. The plots show the pressure from OpenFOAM (blue) vs the analytic solution (red). If the amplitude A is 0.02 (or larger) the solution is correct but for A=0.01 the variation in pressure is much too small (by more than an order of magnitude). In fact there is a more or less discontinuous change in behavior; A=0.014 is fine and A=0.013 is not. I have played with grid resolution, domain size, fvSchemes and fvSolution but to no avail.

The illustrated problems can be run from the attached tarballs. The python functions in scripts/tools/py can be used to make new blockMeshDict files if needed.

Does anyone have any suggestions?

Regards

Tony
Attached Images
 p_01.png (28.5 KB, 17 views) p_02.png (38.7 KB, 15 views)
Attached Files
 stefanFoam.tar.gz (2.8 KB, 6 views) stefan2D_01.tar.gz (31.9 KB, 3 views) stefan2D_02.tar.gz (41.3 KB, 3 views)

Last edited by tladd; May 23, 2014 at 08:12. Reason: Correct x to -x in paragraph 2 (after simply)

 Thread Tools Display Modes Linear Mode

 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 OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post Combas SU2 4 March 28, 2014 16:48 [ANSYS Meshing] Problem with axisymmetric solver Rasel ANSYS Meshing & Geometry 0 June 20, 2012 04:35 cth_yao CFX 0 February 17, 2012 01:52 ICL OpenFOAM 0 October 8, 2011 14:16 yellow-stuff Main CFD Forum 0 September 25, 2009 01:26

All times are GMT -4. The time now is 17:01.