|
[Sponsors] |
December 10, 2011, 01:35 |
multi block error
|
#1 |
New Member
S.Elyasi
Join Date: Jun 2011
Location: IRAN
Posts: 11
Rep Power: 14 |
dear all
i work in a model with multi block method but i dont know why the multi block error(mlbk error) is so great? |
|
December 12, 2011, 00:43 |
|
#2 |
Senior Member
michael barkhudarov
Join Date: Mar 2009
Location: Sante Fe, New Mexico, USA
Posts: 336
Rep Power: 18 |
you mean volume error? The error is computed by comparing the flow rate on each side of an inter-block boundary and summing it over all inter-block boundaries.
The error would be non-zero if the flow rate do not match, and may be more so if any of the following is happening: 1. large change in mesh resolution between adjacent mesh blocks 2. significant fluid break up at the boundary 3. poor convergence of the pressure solver What version are you running? There is also ain input variable called inter-block boundary interpolation coefficient whose value varies from 0 to 1, with the default value of 0.25. You may want to raise it to get volume conservation. |
|
December 12, 2011, 01:16 |
question
|
#3 |
New Member
S.Elyasi
Join Date: Jun 2011
Location: IRAN
Posts: 11
Rep Power: 14 |
hi and thanks
my software version is 9.3 in iran i couldn't find 9.4 version of it where is inter-block boundary interpolation coefficient is necessary to check it? what is the allaowable limitation of it? ava whit the best regards |
|
December 12, 2011, 11:06 |
|
#4 |
Senior Member
michael barkhudarov
Join Date: Mar 2009
Location: Sante Fe, New Mexico, USA
Posts: 336
Rep Power: 18 |
it's under Numerics > Convergence Controls for pressure solvers, at the very bottom. If you did not change it, it must be at the default, which usually works fine. When it is =0, the coupling between blocks is done only through pressure, when it is =1 - through velocity. The default of 0.25 means 25% velocity and 75% pressure.
|
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
CGNS Compiling | Diego | Main CFD Forum | 17 | December 21, 2014 01:40 |
[swak4Foam] GroovyBC the dynamic cousin of funkySetFields that lives on the suburb of the mesh | gschaider | OpenFOAM Community Contributions | 300 | October 29, 2014 18:00 |
c++ libraries and solver compiling | vaina74 | OpenFOAM Installation | 13 | February 3, 2012 17:43 |
Installation OF1.5-dev | ttdtud | OpenFOAM Installation | 46 | May 5, 2009 02:32 |
OpenFOAM on MinGW crosscompiler hosted on Linux | allenzhao | OpenFOAM Installation | 127 | January 30, 2009 19:08 |