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

buoyantSimpleFoam -- circuitBoardCooling --- velocity iteration is gone?

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

Reply
 
LinkBack Thread Tools Display Modes
Old   February 18, 2014, 06:39
Default buoyantSimpleFoam -- circuitBoardCooling --- velocity iteration is gone?
  #1
Member
 
Cong
Join Date: Nov 2012
Posts: 77
Rep Power: 4
wc34071209 is on a distinguished road
Hello Foamers,

When I was doing the circuitBoardingCooling tutorial, I noticed in the output log file that velocity U iterations are gone.

I am wondering what is behind this ?

Can anybody tell me something about it?


------------

Also in my own case, after one iteration, it suddenly blowed up. Can anybody know how to rescue it?

--

Starting time loop

Time = 1

smoothSolver: Solving for h, Initial residual = 0.999999760734241, Final residual = 0.0739844526791796, No Iterations 2
GAMG: Solving for p_rgh, Initial residual = 0.670879701157613, Final residual = 0.00515467031237578, No Iterations 10
GAMG: Solving for p_rgh, Initial residual = 0.894001123688478, Final residual = 0.00856064876150383, No Iterations 4
time step continuity errors : sum local = 0.239582634384328, global = -0.00338366580637759, cumulative = -0.00338366580637759
rho max/min : 1.20719519360923 1.14427087541347
smoothSolver: Solving for omega, Initial residual = 0.955316700148856, Final residual = 0.0634787254801369, No Iterations 4
smoothSolver: Solving for k, Initial residual = 0.999999999999505, Final residual = 0.00103042674222991, No Iterations 1
ExecutionTime = 9.29 s ClockTime = 9 s

Time = 2

smoothSolver: Solving for h, Initial residual = 0.999325490078903, Final residual = 0.0244002703888714, No Iterations 2
GAMG: Solving for p_rgh, Initial residual = 0.988285478738131, Final residual = 3.34337551006217e+61, No Iterations 25
GAMG: Solving for p_rgh, Initial residual = 0.992397990431178, Final residual = 2.4147324455547e+64, No Iterations 25
time step continuity errors : sum local = 5.91744896417765e+128, global = -1.05316590213318e+126, cumulative = -1.05316590213318e+126
rho max/min : 602.133880892008 -142.544096582093
smoothSolver: Solving for omega, Initial residual = 1, Final residual = 0.0241920534931177, No Iterations 2
bounding omega, min: -7.93695792121957e+131 max: 7.45791093353902e+134 average: 4.42408455315227e+129
smoothSolver: Solving for k, Initial residual = 0.863355892782795, Final residual = 0.00502742854378505, No Iterations 1
bounding k, min: -0.0057214152428458 max: 0.00532875391960471 average: 0.000455092432860109
ExecutionTime = 19.81 s ClockTime = 19 s

Time = 3

[0] #0 [1] #0 [2] #0 [3] #0 Foam::error:rintStack(Foam::Ostream&)Foam::error :rintStack(Foam::Ostream&)Foam::error:rintStac k(Foam::Ostream&)Foam::error:rintStack(Foam::Ost ream&) at ??:?
[2] #1 Foam::sigFpe::sigHandler(int) at ??:?
[0] #1 Foam::sigFpe::sigHandler(int) at ??:?
[1] #1 Foam::sigFpe::sigHandler(int) at ??:?
[3] #1 Foam::sigFpe::sigHandler(int) at ??:?
[0] #2 at ??:?
[3] #2 at ??:?
[2] #2 at ??:?
[1] #2 in "/lib/x86_64-linux-gnu/libc.so.6" in "/lib/x86_64-linux-gnu/libc.so.6"
[0] #3
[3] #3 Foam::multiply(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> const&)Foam::multiply(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> const&) in "/lib/x86_64-linux-gnu/libc.so.6"
[1] #3 Foam::multiply(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> const&) in "/lib/x86_64-linux-gnu/libc.so.6"
[2] #3 Foam::multiply(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> const&) at ??:?
[1] #4 Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam:perator*<Foam::fvPatchField, Foam::volMesh>(Foam::tmp<Foam::GeometricField<doub le, Foam::fvPatchField, Foam::volMesh> > const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) at ??:?
[2] #4 Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam:perator*<Foam::fvPatchField, Foam::volMesh>(Foam::tmp<Foam::GeometricField<doub le, Foam::fvPatchField, Foam::volMesh> > const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) at ??:?
[3] #4 Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam:perator*<Foam::fvPatchField, Foam::volMesh>(Foam::tmp<Foam::GeometricField<doub le, Foam::fvPatchField, Foam::volMesh> > const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) at ??:?
[0] #4 Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam:perator*<Foam::fvPatchField, Foam::volMesh>(Foam::tmp<Foam::GeometricField<doub le, Foam::fvPatchField, Foam::volMesh> > const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) at ??:?
[2] #5 at ??:?
[3] #5 Foam::fv::boundedConvectionScheme<double>::fvcDiv( Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) const at Foam::fv::boundedConvectionScheme<double>::fvcDiv( Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) const??:?
[0] #5 Foam::fv::boundedConvectionScheme<double>::fvcDiv( Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) const at ??:?
:
wc34071209 is offline   Reply With Quote

Old   February 18, 2014, 06:52
Default
  #2
Senior Member
 
Alexey Matveichev
Join Date: Aug 2011
Location: Nancy, France
Posts: 1,109
Rep Power: 19
alexeym will become famous soon enoughalexeym will become famous soon enough
Hi,

If you take a look at fvSolution there is subdict SIMPLE

Code:
SIMPLE
{
    momentumPredictor no;
...
}
Cause there is no momentum predictor step there is no lines in the log for U equation. If you change momentuPredictor to yes, velocity iterations will return.
alexeym is offline   Reply With Quote

Old   February 18, 2014, 07:00
Default
  #3
Member
 
Cong
Join Date: Nov 2012
Posts: 77
Rep Power: 4
wc34071209 is on a distinguished road
Thanks a lot.

Now I want to know under what condition we don't need momentum prediction and under what conditions we need.
wc34071209 is offline   Reply With Quote

Old   February 18, 2014, 08:10
Default
  #4
Senior Member
 
Alexey Matveichev
Join Date: Aug 2011
Location: Nancy, France
Posts: 1,109
Rep Power: 19
alexeym will become famous soon enoughalexeym will become famous soon enough
There's Google (or the forum search), you know...

One of the explanations:

When to set momentumPredictor to Yes
alexeym is offline   Reply With Quote

Reply

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
LES and TKE calculations MST Main CFD Forum 2 August 8, 2013 03:51
Radial velocity and tangential velocity on centrifugal fan, johnnyp FLUENT 2 May 24, 2013 07:10
how to compute relative velocity from absolute? spk Main CFD Forum 3 July 9, 2010 08:42
ATTENTION! Reliability problems in CFX 5.7 Joseph CFX 14 April 20, 2010 15:45
Velocity in Porous medium : HELP! HELP! HELP! Kali Sanjay Phoenics 0 November 6, 2006 07:10


All times are GMT -4. The time now is 16:15.