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

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::printStack(Foam::Ostream&)Foam::error ::printStack(Foam::Ostream&)Foam::error::printStac k(Foam::Ostream&)Foam::error::printStack(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::operator*<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::operator*<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::operator*<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::operator*<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 ??:?
:

Hi,

If you take a look at fvSolution there is subdict SIMPLE

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.

Thanks a lot.

Now I want to know under what condition we don't need momentum prediction and under what conditions we need.

There's Google (or the forum search), you know...

One of the explanations:

http://www.cfd-online.com/Forums/ope...tml#post191166