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Compressor Simulation using rhoPimpleDyMFoam

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Old   November 10, 2014, 00:52
Default
  #41
Member
 
Abhijit
Join Date: Jul 2014
Posts: 75
Rep Power: 9
Jetfire is on a distinguished road
@RodriguezFatz
Code:
Does the omega-bounding vanish, if you use the laplacian-setting I suggested?
I tried changing the Laplacian Setting to Gauss Linear uncorrected while the simulation was running. Here is the output , Omega is not bounded in later time steps.
Code:
Courant Number mean: 0.000113778 max: 1
deltaT = 1.41782e-09
Time = 6.59824e-07

solidBodyMotionFunctions::rotatingMotion::transformation(): Time =  6.59824e-07 transformation: ((0 0 0) (0.999946 (0.0103643 0 0)))
AMI: Creating addressing and weights between 1900 source faces and 32076 target faces
AMI: Patch source sum(weights) min/max/average = 0.995413, 1, 0.999762
AMI: Patch target sum(weights) min/max/average = 0.474286, 1.00002, 0.996806
AMI: Creating addressing and weights between 17748 source faces and 5456 target faces
AMI: Patch source sum(weights) min/max/average = 0.443604, 1.05059, 1.00015
AMI: Patch target sum(weights) min/max/average = 0.519849, 1.00249, 0.999845
AMI: Creating addressing and weights between 17839 source faces and 1957 target faces
AMI: Patch source sum(weights) min/max/average = 0.86998, 1, 0.999108
AMI: Patch target sum(weights) min/max/average = 0.991279, 1, 0.99992
GAMG:  Solving for pcorr, Initial residual = 1, Final residual = 0.00915686, No Iterations 54
GAMG:  Solving for pcorr, Initial residual = 0.0243898, Final residual = 0.00464874, No Iterations 1
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
rhoEqn max/min : 2.2097 0.276597
smoothSolver:  Solving for Ux, Initial residual = 3.16377e-05, Final residual = 2.14271e-09, No Iterations 1
smoothSolver:  Solving for Uy, Initial residual = 0.00139322, Final residual = 1.18808e-07, No Iterations 1
smoothSolver:  Solving for Uz, Initial residual = 0.00157917, Final residual = 1.27902e-07, No Iterations 1
smoothSolver:  Solving for h, Initial residual = 0.000472102, Final residual = 3.83132e-08, No Iterations 1
GAMG:  Solving for p, Initial residual = 6.76418e-05, Final residual = 2.45351e-13, No Iterations 1
GAMG:  Solving for p, Initial residual = 1.21131e-09, Final residual = 1.21131e-09, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000171506, global = -0.000151276, cumulative = -0.0929682
rho max/min : 2 0.5
GAMG:  Solving for p, Initial residual = 1.15378e-07, Final residual = 1.15378e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 1.15378e-07, Final residual = 1.15378e-07, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000171515, global = -0.000151276, cumulative = -0.0931195
rho max/min : 2 0.5
GAMG:  Solving for p, Initial residual = 1.153e-07, Final residual = 1.153e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 1.153e-07, Final residual = 1.153e-07, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000171515, global = -0.000151276, cumulative = -0.0932708
rho max/min : 2 0.5
smoothSolver:  Solving for omega, Initial residual = 2.11641e-06, Final residual = 1.37612e-10, No Iterations 1
bounding omega, min: -6204.38 max: 6.34422e+09 average: 2.18357e+06
smoothSolver:  Solving for k, Initial residual = 2.41327e-05, Final residual = 9.59219e-10, No Iterations 1
ExecutionTime = 70114.9 s  ClockTime = 94366 s

regIOobject::readIfModified() : 
    Re-reading object fvSchemes from file  "/home/eatin/OpenFOAM/eatin-2.3.0/run/tutorials/TurboCharger/Trial_run/system/fvSchemes"
Courant Number mean: 0.00011376 max: 1
deltaT = 1.41782e-09
Time = 6.61242e-07

solidBodyMotionFunctions::rotatingMotion::transformation(): Time =  6.61242e-07 transformation: ((0 0 0) (0.999946 (0.0103866 0 0)))
AMI: Creating addressing and weights between 1900 source faces and 32076 target faces
AMI: Patch source sum(weights) min/max/average = 0.995413, 1, 0.999762
AMI: Patch target sum(weights) min/max/average = 0.474033, 1, 0.996806
AMI: Creating addressing and weights between 17748 source faces and 5456 target faces
AMI: Patch source sum(weights) min/max/average = 0.439444, 1.05157, 1.00015
AMI: Patch target sum(weights) min/max/average = 0.519845, 1.00248, 0.999845
AMI: Creating addressing and weights between 17839 source faces and 1957 target faces
AMI: Patch source sum(weights) min/max/average = 0.86998, 1, 0.999108
AMI: Patch target sum(weights) min/max/average = 0.991279, 1, 0.99992
GAMG:  Solving for pcorr, Initial residual = 1, Final residual = 0.00996615, No Iterations 57
GAMG:  Solving for pcorr, Initial residual = 1.31767e-05, Final residual = 1.31767e-05, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
rhoEqn max/min : 2.02652 0.480629
smoothSolver:  Solving for Ux, Initial residual = 3.16636e-05, Final residual = 2.11836e-09, No Iterations 1
smoothSolver:  Solving for Uy, Initial residual = 0.00140312, Final residual = 1.13106e-07, No Iterations 1
smoothSolver:  Solving for Uz, Initial residual = 0.00159988, Final residual = 1.2634e-07, No Iterations 1
smoothSolver:  Solving for h, Initial residual = 0.000464709, Final residual = 3.32125e-08, No Iterations 1
GAMG:  Solving for p, Initial residual = 6.73208e-05, Final residual = 4.49914e-13, No Iterations 1
GAMG:  Solving for p, Initial residual = 4.48889e-13, Final residual = 4.48889e-13, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000171907, global = -0.000151647, cumulative = -0.0934224
rho max/min : 2 0.5
GAMG:  Solving for p, Initial residual = 1.16407e-07, Final residual = 1.16407e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 1.16407e-07, Final residual = 1.16407e-07, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000171916, global = -0.000151647, cumulative = -0.0935741
rho max/min : 2 0.5
GAMG:  Solving for p, Initial residual = 1.16329e-07, Final residual = 1.16329e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 1.16329e-07, Final residual = 1.16329e-07, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000171916, global = -0.000151647, cumulative = -0.0937257
rho max/min : 2 0.5
smoothSolver:  Solving for omega, Initial residual = 2.129e-06, Final residual = 2.07432e-10, No Iterations 1
smoothSolver:  Solving for k, Initial residual = 2.40993e-05, Final residual = 1.02225e-09, No Iterations 1
ExecutionTime = 70251.8 s  ClockTime = 94547 s

Courant Number mean: 0.000113739 max: 1
deltaT = 1.41781e-09
Time = 6.6266e-07

solidBodyMotionFunctions::rotatingMotion::transformation(): Time =  6.6266e-07 transformation: ((0 0 0) (0.999946 (0.0104089 0 0)))
AMI: Creating addressing and weights between 1900 source faces and 32076 target faces
AMI: Patch source sum(weights) min/max/average = 0.995413, 1, 0.999762
AMI: Patch target sum(weights) min/max/average = 0.473781, 1, 0.996806
AMI: Creating addressing and weights between 17748 source faces and 5456 target faces
AMI: Patch source sum(weights) min/max/average = 0.435284, 1.05167, 1.00015
AMI: Patch target sum(weights) min/max/average = 0.51984, 1.00247, 0.999844
AMI: Creating addressing and weights between 17839 source faces and 1957 target faces
AMI: Patch source sum(weights) min/max/average = 0.86998, 1, 0.999108
AMI: Patch target sum(weights) min/max/average = 0.991279, 1, 0.99992
GAMG:  Solving for pcorr, Initial residual = 1, Final residual = 0.00919969, No Iterations 54
GAMG:  Solving for pcorr, Initial residual = 1.21672e-05, Final residual = 1.21672e-05, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
rhoEqn max/min : 2.03418 0.471993
smoothSolver:  Solving for Ux, Initial residual = 3.16366e-05, Final residual = 2.11287e-09, No Iterations 1
smoothSolver:  Solving for Uy, Initial residual = 0.00140093, Final residual = 1.12678e-07, No Iterations 1
smoothSolver:  Solving for Uz, Initial residual = 0.00159565, Final residual = 1.25571e-07, No Iterations 1
smoothSolver:  Solving for h, Initial residual = 0.000461355, Final residual = 3.36557e-08, No Iterations 1
GAMG:  Solving for p, Initial residual = 6.71918e-05, Final residual = 6.20407e-13, No Iterations 1
GAMG:  Solving for p, Initial residual = 6.18972e-13, Final residual = 6.18972e-13, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000172306, global = -0.000152017, cumulative = -0.0938777
rho max/min : 2 0.5
GAMG:  Solving for p, Initial residual = 1.16604e-07, Final residual = 1.16604e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 1.16604e-07, Final residual = 1.16604e-07, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000172314, global = -0.000152017, cumulative = -0.0940298
rho max/min : 2 0.5
GAMG:  Solving for p, Initial residual = 1.16525e-07, Final residual = 1.16525e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 1.16525e-07, Final residual = 1.16525e-07, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000172314, global = -0.000152017, cumulative = -0.0941818
rho max/min : 2 0.5
smoothSolver:  Solving for omega, Initial residual = 2.12444e-06, Final residual = 9.55552e-11, No Iterations 1
smoothSolver:  Solving for k, Initial residual = 2.40609e-05, Final residual = 9.28125e-10, No Iterations 1
ExecutionTime = 70374.2 s  ClockTime = 94719 s

Courant Number mean: 0.000113719 max: 1
deltaT = 1.41781e-09
Time = 6.64078e-07

solidBodyMotionFunctions::rotatingMotion::transformation(): Time =  6.64078e-07 transformation: ((0 0 0) (0.999946 (0.0104311 0 0)))
AMI: Creating addressing and weights between 1900 source faces and 32076 target faces
AMI: Patch source sum(weights) min/max/average = 0.995413, 1, 0.999762
AMI: Patch target sum(weights) min/max/average = 0.47353, 1.00001, 0.996806
AMI: Creating addressing and weights between 17748 source faces and 5456 target faces
AMI: Patch source sum(weights) min/max/average = 0.431124, 1.05171, 1.00015
AMI: Patch target sum(weights) min/max/average = 0.519832, 1.00246, 0.999844
AMI: Creating addressing and weights between 17839 source faces and 1957 target faces
AMI: Patch source sum(weights) min/max/average = 0.86998, 1, 0.999108
AMI: Patch target sum(weights) min/max/average = 0.991279, 1, 0.99992
GAMG:  Solving for pcorr, Initial residual = 1, Final residual = 0.00988888, No Iterations 57
GAMG:  Solving for pcorr, Initial residual = 1.30742e-05, Final residual = 1.30742e-05, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
rhoEqn max/min : 2.02687 0.482841
smoothSolver:  Solving for Ux, Initial residual = 3.1612e-05, Final residual = 2.10315e-09, No Iterations 1
smoothSolver:  Solving for Uy, Initial residual = 0.00139863, Final residual = 1.12206e-07, No Iterations 1
smoothSolver:  Solving for Uz, Initial residual = 0.00159138, Final residual = 1.24932e-07, No Iterations 1
smoothSolver:  Solving for h, Initial residual = 0.000457716, Final residual = 3.34466e-08, No Iterations 1
GAMG:  Solving for p, Initial residual = 6.70692e-05, Final residual = 5.14521e-13, No Iterations 1
GAMG:  Solving for p, Initial residual = 5.13329e-13, Final residual = 5.13329e-13, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000172702, global = -0.000152384, cumulative = -0.0943342
rho max/min : 2 0.5
GAMG:  Solving for p, Initial residual = 1.16259e-07, Final residual = 1.16259e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 1.16259e-07, Final residual = 1.16259e-07, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.00017271, global = -0.000152384, cumulative = -0.0944865
rho max/min : 2 0.5
GAMG:  Solving for p, Initial residual = 1.16181e-07, Final residual = 1.16181e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 1.16181e-07, Final residual = 1.16181e-07, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.00017271, global = -0.000152384, cumulative = -0.0946389
rho max/min : 2 0.5
smoothSolver:  Solving for omega, Initial residual = 2.12412e-06, Final residual = 9.48272e-11, No Iterations 1
smoothSolver:  Solving for k, Initial residual = 2.40277e-05, Final residual = 9.26293e-10, No Iterations 1
ExecutionTime = 70511.2 s  ClockTime = 94911 s

Courant Number mean: 0.000113698 max: 1
deltaT = 1.4178e-09
Time = 6.65496e-07

solidBodyMotionFunctions::rotatingMotion::transformation(): Time =  6.65496e-07 transformation: ((0 0 0) (0.999945 (0.0104534 0 0)))
AMI: Creating addressing and weights between 1900 source faces and 32076 target faces
AMI: Patch source sum(weights) min/max/average = 0.995413, 1, 0.999762
AMI: Patch target sum(weights) min/max/average = 0.47328, 1, 0.996806
AMI: Creating addressing and weights between 17748 source faces and 5456 target faces
AMI: Patch source sum(weights) min/max/average = 0.447838, 1.05176, 1.00015
AMI: Patch target sum(weights) min/max/average = 0.519822, 1.00245, 0.99986
AMI: Creating addressing and weights between 17839 source faces and 1957 target faces
AMI: Patch source sum(weights) min/max/average = 0.86998, 1, 0.999108
AMI: Patch target sum(weights) min/max/average = 0.991279, 1, 0.99992
GAMG:  Solving for pcorr, Initial residual = 1, Final residual = 0.00924126, No Iterations 54
GAMG:  Solving for pcorr, Initial residual = 1.2222e-05, Final residual = 1.2222e-05, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
rhoEqn max/min : 2.03417 0.472107
smoothSolver:  Solving for Ux, Initial residual = 3.15871e-05, Final residual = 2.09785e-09, No Iterations 1
smoothSolver:  Solving for Uy, Initial residual = 0.00139647, Final residual = 1.11942e-07, No Iterations 1
smoothSolver:  Solving for Uz, Initial residual = 0.0015874, Final residual = 1.24392e-07, No Iterations 1
smoothSolver:  Solving for h, Initial residual = 0.000453908, Final residual = 3.31894e-08, No Iterations 1
GAMG:  Solving for p, Initial residual = 6.69419e-05, Final residual = 6.18263e-13, No Iterations 1
GAMG:  Solving for p, Initial residual = 6.16834e-13, Final residual = 6.16834e-13, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000173096, global = -0.000152751, cumulative = -0.0947917
rho max/min : 2 0.5
GAMG:  Solving for p, Initial residual = 1.15716e-07, Final residual = 1.15716e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 1.15716e-07, Final residual = 1.15716e-07, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000173105, global = -0.000152751, cumulative = -0.0949444
rho max/min : 2 0.5
GAMG:  Solving for p, Initial residual = 1.15638e-07, Final residual = 1.15638e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 1.15638e-07, Final residual = 1.15638e-07, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000173105, global = -0.000152751, cumulative = -0.0950972
rho max/min : 2 0.5
smoothSolver:  Solving for omega, Initial residual = 2.12485e-06, Final residual = 9.43144e-11, No Iterations 1
smoothSolver:  Solving for k, Initial residual = 2.39952e-05, Final residual = 9.24967e-10, No Iterations 1
ExecutionTime = 70649.8 s  ClockTime = 95106 s

Courant Number mean: 0.000113677 max: 1.00001
deltaT = 1.41779e-09
Time = 6.66913e-07

solidBodyMotionFunctions::rotatingMotion::transformation(): Time =  6.66913e-07 transformation: ((0 0 0) (0.999945 (0.0104757 0 0)))
AMI: Creating addressing and weights between 1900 source faces and 32076 target faces
AMI: Patch source sum(weights) min/max/average = 0.995413, 1, 0.999762
AMI: Patch target sum(weights) min/max/average = 0.473032, 1.00001, 0.996806
AMI: Creating addressing and weights between 17748 source faces and 5456 target faces
AMI: Patch source sum(weights) min/max/average = 0.447836, 1.0518, 1.00015
AMI: Patch target sum(weights) min/max/average = 0.51981, 1.00244, 0.99986
AMI: Creating addressing and weights between 17839 source faces and 1957 target faces
AMI: Patch source sum(weights) min/max/average = 0.86998, 1, 0.999108
AMI: Patch target sum(weights) min/max/average = 0.991279, 1, 0.99992
GAMG:  Solving for pcorr, Initial residual = 1, Final residual = 0.00988871, No Iterations 57
GAMG:  Solving for pcorr, Initial residual = 1.30738e-05, Final residual = 1.30738e-05, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
rhoEqn max/min : 2.02717 0.48285
smoothSolver:  Solving for Ux, Initial residual = 3.15639e-05, Final residual = 2.09028e-09, No Iterations 1
smoothSolver:  Solving for Uy, Initial residual = 0.00139419, Final residual = 1.11562e-07, No Iterations 1
smoothSolver:  Solving for Uz, Initial residual = 0.00158337, Final residual = 1.23881e-07, No Iterations 1
smoothSolver:  Solving for h, Initial residual = 0.000450021, Final residual = 3.2803e-08, No Iterations 1
GAMG:  Solving for p, Initial residual = 6.68107e-05, Final residual = 4.95164e-13, No Iterations 1
GAMG:  Solving for p, Initial residual = 4.94024e-13, Final residual = 4.94024e-13, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.00017349, global = -0.000153117, cumulative = -0.0952503
rho max/min : 2 0.5
GAMG:  Solving for p, Initial residual = 1.15139e-07, Final residual = 1.15139e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 1.15139e-07, Final residual = 1.15139e-07, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000173498, global = -0.000153117, cumulative = -0.0954034
rho max/min : 2 0.5
GAMG:  Solving for p, Initial residual = 1.15061e-07, Final residual = 1.15061e-07, No Iterations 0
GAMG:  Solving for p, Initial residual = 1.15061e-07, Final residual = 1.15061e-07, No Iterations 0
diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0.000173498, global = -0.000153117, cumulative = -0.0955565
rho max/min : 2 0.5
smoothSolver:  Solving for omega, Initial residual = 2.12539e-06, Final residual = 9.40374e-11, No Iterations 1
smoothSolver:  Solving for k, Initial residual = 2.39606e-05, Final residual = 9.23655e-10, No Iterations 1
ExecutionTime = 70803.7 s  ClockTime = 95324 s
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Old   November 10, 2014, 00:53
Default
  #42
Member
 
Abhijit
Join Date: Jul 2014
Posts: 75
Rep Power: 9
Jetfire is on a distinguished road
But Later, after a few iterations my simulation crashes showing this


Code:
[7] #0  Foam::error::printStack(Foam::Ostream&) in  "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
[7] #1  Foam::sigFpe::sigHandler(int) in "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
[7] #2   in "/lib/x86_64-linux-gnu/libc.so.6"
[7] #3  Foam::hePsiThermo<Foam::psiThermo,  Foam::pureMixture<Foam::sutherlandTransport<Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie>   >, Foam::sensibleEnthalpy> > > >::calculate() in  "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/lib/libfluidThermophysicalModels.so"
[7] #4  Foam::hePsiThermo<Foam::psiThermo,  Foam::pureMixture<Foam::sutherlandTransport<Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie>   >, Foam::sensibleEnthalpy> > > >::correct() in  "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/lib/libfluidThermophysicalModels.so"
[7] #5  
[7]  in "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/bin/rhoPimpleDyMFoam"
[7] #6  __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
[7] #7  
[7]  in "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/bin/rhoPimpleDyMFoam"
[EAT-Standalone:13533] *** Process received signal ***
[EAT-Standalone:13533] Signal: Floating point exception (8)
[EAT-Standalone:13533] Signal code:  (-6)
[EAT-Standalone:13533] Failing at address: 0x3e8000034dd
[EAT-Standalone:13533] [ 0] /lib/x86_64-linux-gnu/libc.so.6(+0x364a0) [0x7fc667b0b4a0]
[EAT-Standalone:13533] [ 1] /lib/x86_64-linux-gnu/libc.so.6(gsignal+0x35) [0x7fc667b0b425]
[EAT-Standalone:13533] [ 2] /lib/x86_64-linux-gnu/libc.so.6(+0x364a0) [0x7fc667b0b4a0]
[EAT-Standalone:13533] [ 3]  /home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/lib/libfluidThermophysicalModels.so(_ZN4Foam11hePsiThermoINS_9psiThermoENS_11pureMixtureINS_19sutherlandTransportINS_7species6thermoINS_12hConstThermoINS_10perfectGasINS_6specieEEEEENS_16sensibleEnthalpyEEEEEEEE9calculateEv+0x2ab)   [0x7fc66d071f0b]
[EAT-Standalone:13533] [ 4]  /home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/lib/libfluidThermophysicalModels.so(_ZN4Foam11hePsiThermoINS_9psiThermoENS_11pureMixtureINS_19sutherlandTransportINS_7species6thermoINS_12hConstThermoINS_10perfectGasINS_6specieEEEEENS_16sensibleEnthalpyEEEEEEEE7correctEv+0x32)   [0x7fc66d07f5f2]
[EAT-Standalone:13533] [ 5] rhoPimpleDyMFoam() [0x41f217]
[EAT-Standalone:13533] [ 6] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xed) [0x7fc667af676d]
[EAT-Standalone:13533] [ 7] rhoPimpleDyMFoam() [0x42660d]
[EAT-Standalone:13533] *** End of error message ***
--------------------------------------------------------------------------
mpirun noticed that process rank 7 with PID 13533 on node EAT-Standalone exited on signal 8 (Floating point exception).
--------------------------------------------------------------------------
[7] #0  Foam::error::printStack(Foam::Ostream&) in  "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
[7] #1  Foam::sigFpe::sigHandler(int) in "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
[7] #2   in "/lib/x86_64-linux-gnu/libc.so.6"
[7] #3  Foam::hePsiThermo<Foam::psiThermo,  Foam::pureMixture<Foam::sutherlandTransport<Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie>   >, Foam::sensibleEnthalpy> > > >::calculate() in  "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/lib/libfluidThermophysicalModels.so"
[7] #4  Foam::hePsiThermo<Foam::psiThermo,  Foam::pureMixture<Foam::sutherlandTransport<Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie>   >, Foam::sensibleEnthalpy> > > >::correct() in  "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/lib/libfluidThermophysicalModels.so"
[7] #5  
[7]  in "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/bin/rhoPimpleDyMFoam"
[7] #6  __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
[7] #7  
[7]  in "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/bin/rhoPimpleDyMFoam"
[EAT-Standalone:13837] *** Process received signal ***
[EAT-Standalone:13837] Signal: Floating point exception (8)
[EAT-Standalone:13837] Signal code:  (-6)
[EAT-Standalone:13837] Failing at address: 0x3e80000360d
[EAT-Standalone:13837] [ 0] /lib/x86_64-linux-gnu/libc.so.6(+0x364a0) [0x7fd517db24a0]
[EAT-Standalone:13837] [ 1] /lib/x86_64-linux-gnu/libc.so.6(gsignal+0x35) [0x7fd517db2425]
[EAT-Standalone:13837] [ 2] /lib/x86_64-linux-gnu/libc.so.6(+0x364a0) [0x7fd517db24a0]
[EAT-Standalone:13837] [ 3]  /home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/lib/libfluidThermophysicalModels.so(_ZN4Foam11hePsiThermoINS_9psiThermoENS_11pureMixtureINS_19sutherlandTransportINS_7species6thermoINS_12hConstThermoINS_10perfectGasINS_6specieEEEEENS_16sensibleEnthalpyEEEEEEEE9calculateEv+0x2ab)   [0x7fd51d318f0b]
[EAT-Standalone:13837] [ 4]  /home/eatin/OpenFOAM/OpenFOAM-2.3.0/platforms/linux64GccDPOpt/lib/libfluidThermophysicalModels.so(_ZN4Foam11hePsiThermoINS_9psiThermoENS_11pureMixtureINS_19sutherlandTransportINS_7species6thermoINS_12hConstThermoINS_10perfectGasINS_6specieEEEEENS_16sensibleEnthalpyEEEEEEEE7correctEv+0x32)   [0x7fd51d3265f2]
[EAT-Standalone:13837] [ 5] rhoPimpleDyMFoam() [0x41f217]
[EAT-Standalone:13837] [ 6] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xed) [0x7fd517d9d76d]
[EAT-Standalone:13837] [ 7] rhoPimpleDyMFoam() [0x42660d]
[EAT-Standalone:13837] *** End of error message ***
--------------------------------------------------------------------------
mpirun noticed that process rank 7 with PID 13837 on node EAT-Standalone exited on signal 8 (Floating point exception).
--------------------------------------------------------------------------
[1]+  Exit 136                mpirun -np 8 rhoPimpleDyMFoam -parallel > log
Can you help me out on what caused this error.
I am unable to attach my output log file as it is exceeding max file size even after compressing it. I will mail it to you if you give me your mail id's.

Thanks
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Old   November 10, 2014, 02:55
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Did you set "default Gauss linear uncorrected"?
I would try to use the "uncorrected" just for the -omega- term. Or firstly better try "default Gauss linear limited 0.5".
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Old   November 10, 2014, 03:00
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ok..

I will change it to Gauss Linear Limited 0.5
Please check post #40
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Old   November 10, 2014, 03:03
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Better ask Tobias about that stuff... I won't be any help.
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Old   November 10, 2014, 03:54
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Hi,

can you give the fvSchemes, fvSolutions and controlDict.
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Old   November 10, 2014, 03:58
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Please check attachments
Attached Files
File Type: gz files.tar.gz (1.3 KB, 19 views)
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Old   November 10, 2014, 05:02
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Thanks,


Try and use the following settings:

controlDict
Code:
deltaT    1e-8;
writeInterval   2e-08;
writePrecision 10;
maxCo 2;


fvSolutions

Code:
    "(rho|U|h)"
    {
        solver          PBiCG;
        preconditioner  DILU;
        tolerance       1e-06;
        relTol          0.1;
    }

    "(rho|U|h)Final"
    {
        $U;
        relTol          0;
    }

    "(k|epsilon|omega)"
    {
        solver          PBiCG;
        preconditioner  DILU;
        tolerance       1e-10;
        relTol          0.1;
    }
    "(k|epsilon|omega)Final"
    {
        $k;
        relTol          0;
    }

PIMPLE
{
         momentumPredictor   yes;
             transonic           no;
             nOuterCorrectors    50;
             nCorrectors         2;
             nNonOrthogonalCorrectors 1;
             turbOnFinalIterOnly false;

             rhoMin          rhoMin [ 1 -3 0 0 0 ] 0.1;
             rhoMax          rhoMax [ 1 -3 0 0 0 ] 2.5;
}

relaxationFactors
{
             fields
             {
                            p         0.3;
                            pFinal  1;
             }
             equations
             {
                         "(U|h|k|epsilon|omega)"   0.4;
                         "(U|h|k|epsilon|omega)Final" 1;
             }
}
fvSchemes
Code:
gradSchemes
{
    default         Gauss linear;
}

divSchemes
{
    default         none;

    div(phi,U)      Gauss upwind; //linearUpwind grad(U);
    div(phi,h)      Gauss upwind; //linearUpwind grad(h);
    div(phi,K)      Gauss linear;
    div(meshPhi,p)  Gauss linear;
    div(phi,k)      Gauss upwind;
    div(phi,omega) Gauss upwind;
    div((muEff*dev2(T(grad(U))))) Gauss linear;
}

laplacianSchemes
{
    default         none ;
    laplacian(rAUf,pcorr)       Gauss linear corrected;
    laplacian(muEff,U)          Gauss linear corrected;
    laplacian(alphaEff,h)       Gauss linear corrected;
    laplacian(rhorAUf,p)        Gauss linear corrected;

    laplacian(DepsilonEff,epsilon)      Gauss linear uncorrected;
    laplacian(DkEff,k)                  Gauss linear uncorrected;
    laplacian(DomegaEff,omega)          Gauss linear uncorrected;

}
What I want to say (mean no harm) but:

I feel very sad that you did not change your files like we mentioned. All advices we gave to you are useless if you do not take it into account. That makes me very sad and especially the imagination that some people offers their time to reading threads, checking out the cases and errors to give any advice to solve the problem is demotivating because if I spend time to a problem and give some advice and none of the advice is used and the thread starter always ask the same questions, its like »time wasted« ... especially in old topics like » using the PIMPLE alogithm

The old posts contained the following changes (that are now included in the three files):
  • I mentioned that you should have a look to the PIMPLE blog
  • I additionally mentioned that it would be nice if you change your solution solver because smoothSolver is not always the best choice. You find nice threads in this forum about this topic.
  • At least Philipp told you to have a look at the first timesteps to check out your solution and maybe change the mesh in that zones which makes trouble. But if I look to your controlDict, I think you never reached your write time and hence that I think you did not check it out or could not check it out.

Again this mean no harm to you but in some cases it makes me very very sad to investigate time for such problems if the hints are not used.

At least - now - I can imagine why there are too less support of advanced FOAM users due to the above mentioned things.


I hope you will »copy paste« or »modify« your files and give feedback.
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Old   November 10, 2014, 05:10
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Just to confirm, your rotor is rotating with 300000 RPM right??
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Old   November 10, 2014, 05:15
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Quote:
Originally Posted by vasava View Post
Just to confirm, your rotor is rotating with 300000 RPM right??
For me I thought its 300 RPM due to the comma 300,000 -> for me 300 RPM, but maybe your are right. If this would be correct (300.000) then there are a few things to change... but never did simulations in that RPM range.
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Old   November 10, 2014, 05:28
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Hi tobi,

I really dint mean to make you sad
I was implementing the changes to the best of my knowledge.
I have read about the PIMPLE ALGORITHM on your blog and tried to implement relaxation factors for variables but ended up getting this
Code:
--> FOAM FATAL ERROR:  previous iteration field IOobject: volScalarField p "/home/eatin/OpenFOAM/OpenFOAM-2.3.0/TurboCharger/Trail_run2/0"    not stored.  Use field.storePrevIter() at start of iteration.      From function GeometricField<Type, PatchField, GeoMesh>::prevIter() const     in file /home/eatin/OpenFOAM/OpenFOAM-2.3.0/src/OpenFOAM/lnInclude/GeometricField.C at line 863.  FOAM aborting
I figured out that i have to include this line in the solver based on replies from some other threads, but i do not know where exactly i have to include it.
Code:
field.storePrevIter( )

Philipp has suggested me to use Gauss linear uncorrected for the omega,As i had no knowledge about the other things in laplacian i changed to default Gauss linear uncorrected for the laplacian schemes. I had posted the output in post #41
then he suggested me to use default Gauss linear limited 0.5. please check post #43

I am using OpenFOAM for the first time and getting to know little about it day by day from experts like you through this forum and reading lot of threads. Please dont think i am not following your instructions, i am trying my level best to first understand your replies and implement them. I really thank you guys for helping me out and really appreaciate your efforts to patiently explain concepts to me.
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Old   November 10, 2014, 05:31
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@vasava

Yes 300000 rpm
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Old   November 10, 2014, 06:07
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Hi,

as I told you its without mean on harm...
  1. you do not need to define all laplacian schemes, I just do it for you... you only set default to linear corrected and all other which should differ from that settings
    has an own entry
  2. I thought you are familiar with openFoam because you did not answered my question due to that topic
  3. If you apply the changes to the rhoPimpleDyMFoam tutorial everything is working fine, therefor it should work for your case too (you use rhoPimpleDyMFoam, arent you?)
  4. Is your case now working with my mentioned changes?
  5. Please start with deltaT = 1e-10;
  6. nOuterCorrectors = 100;
  7. start your case with rhoPimpleDyMFoam > log 2>&1
  8. or in parallel mpirun -np x rhoPimpleDyMFoam -parallel > log 2>&1
  9. Upload your log file


  • I am sorry but my browser did not showed the posts from 42 - 45!!!
  • Now I get the point why you change it to limited 0.5
  • The residual control should work, what did you insert that this error occured?
  • If you have problems you have to tell it » I can not check what you did without information
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Old   November 10, 2014, 06:24
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Hi tobi,

Ya have modified the files as you suggested, changed the timStep to 1e-10 and running the simulation. Lot of pimple iterations per time step.Not even completed the first timeStep.

Will update you soon with the output.


Can you please check the output i got with the previous settings , they are here

http://www.cfd-online.com/Forums/ope...dymfoam-3.html

Post #41 and #42. Is the error because of my thermoPhysicalProperties ?? please confirm

Code:
/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  2.3.0                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    location    "constant";
    object      thermophysicalProperties;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

thermoType
{
    type            hePsiThermo;
    mixture         pureMixture;
    transport       sutherland;
    thermo          hConst;
    equationOfState perfectGas;
    specie          specie;
    energy          sensibleEnthalpy;
}

mixture
{
    specie
    {
        nMoles      1;  // No. of moles
        molWeight   28.96; // Molecular weight of air
    }
    thermodynamics
    {
        Cp          1.0063e+3; // specific heat
        Hf          2.544e+06; // heat of fusion calculated using h=2501+1.84t where t=25 0C
    }
    transport
    {
       // mu        1.844e-05; // dynamic viscosity
       // Pr        0.7;  // prandtl number

        As              1.458e-06;  //sutherland coeffecient
        Ts              110.4;  //sutherland temperature
    }
}


// ************************************************************************* //
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Old   November 10, 2014, 06:42
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Few clarifications

1. Should i increase my timeStep to 1e-09 after few iterations , this was calculated for courant no. 1? or 1e-10 is fine

2. Lot of pimple iterations per timeStep , taking high computational time , is this alright or shall i decrease the nOuterCorrectors ? ( Not even 1 timeStep completed yet )

3. Yes , I am using rhoPimpleDyMFoam and have implemented this change in the code mentioned here http://www.openfoam.org/mantisbt/view.php?id=909
to include the mesh motion. The term was missing before.
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Old   November 10, 2014, 07:08
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Hi,

due to the output I think its your thermodynamic model. You divide through zero (floating point exeption). Problem is that I dont know when this error occur but I think befor calculating the enthalpy h. Then you have problems with the thermodynamic class but I think in your case its more due to some instability problems of your solution.

So just use my mentioned modifications and have a look if everything is working. Use pyFoam for that (if you do not know it, it would be nice to check it out). Especially pyFoamPlotWatcher.py...
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Old   November 10, 2014, 07:23
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Quote:
Originally Posted by Jetfire View Post
Few clarifications

1. Should i increase my timeStep to 1e-09 after few iterations , this was calculated for courant no. 1? or 1e-10 is fine
No its automatically updated till you reach Co = 2.
Quote:
2. Lot of pimple iterations per timeStep , taking high computational time , is this alright or shall i decrease the nOuterCorrectors ? ( Not even 1 timeStep completed yet )
That is the sence of PIMPLE, merged PISO - SIMPLE. In the PIMPLE Loop you underrelax your solution (especially for stiff systems). After you reached your residualControl it will leave the LOOP and go to the next time step. The advantage is,
  • stability
  • bigger time steps


But I forgot something. The fvSolution file should look like that:
Code:
PIMPLE 
{
    momentumPredictor   yes;
    transonic           no;
    nOuterCorrectors    100;
    nCorrectors         2;
    nNonOrthogonalCorrectors 1;
    turbOnFinalIterOnly false;

    rhoMin          rhoMin [ 1 -3 0 0 0 ] 0.1;
    rhoMax         rhoMax [ 1 -3 0 0 0 ] 2.5; 

    residualControl     
    {         
             "(U|k|omega)"
             {
                      tolerance  1e-5;
                     relTol     0;
             }

              p
             {
                 tolerance  1e-4;
                      relTol     0;    
              }     
     }
}
For you, » its also in my blog «

Now you underrelax the equations or matrixes and be much more stable. You use this relaxation factors till you reach your residual control criterions for each variable you set and the last iteration is with no relaxation factors (factors = 1). Normally the first time step will not converge if you have a complex problem but after a few time steps your Pimple loop can decrease from 200 loops to 12 loops. And you will get bigger timesteps and stable simulation. Thats the reason why PIMPLE is better than PISO if you want to have a look at bigger time steps.

If you set nOuterCorrections to 1 then you have PISO mode. Therefor maxCo should be set to 0.1 - 0.7 (depend on your case) and you are not allowed to underrelax anymore. If you use PISO your dT is something around 1e-5 to 1e-8 (depend on case and problem). For PIMPLE you can get much bigger timesteps. One iteration is more expensive but you go on in time faster.

Hope its clear now.
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Old   November 11, 2014, 03:16
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@Tobi: Are rhoMin and rhoMax the value of minimum and maximum density from rhoCoeffs function respectively??
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Old   November 11, 2014, 03:30
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Hi ,

So far the simulation is running well, it has reached to 8.5e-08 s.
I have included the residual control and the pimple is getting converged for 35 iterations each time step.

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Old   November 11, 2014, 04:36
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Quote:
Originally Posted by Jetfire View Post
Hi ,

So far the simulation is running well, it has reached to 8.5e-08 s.
I have included the residual control and the pimple is getting converged for 35 iterations each time step.

Very nice... like I told you ...
Now you have to analyse your output. To fasten up the simulation you have several options now:

  • increasing/decreasing nCorrectors, depend on your pressure eqn. maybe if you increase it to 3 you will leave the PIMPLE loop after 8 iterations - you have to play around
  • Change the relaxation factors (after a while it could be possible to increase it)
  • Befor starting a simulation you can renumber your mesh (my college gained 24% faster calculation compared with unrenumbered mesh)
  • Decompose your mesh that the faces between the processors are weighted. It makes no sence to have processors which share 10 faces with other processors.
    (scotch is not always the best)
Example:
One calculation needed 3 weeks with 18 cores, with correct decomposing and 10 cores it took me 4 days less

  • But be aware that you are sure that your residual control is well defined. Maybe the tolerance for p = 1e-4 is not sufficient or for k, omega, and U.
  • Also be sure to have turbOnFinalIterOnly » false (due to accuracy)
  • Also check the iterations of your equations. If k, epsilon are 0 maybe it is better to solve these equations till 1e-12...


Quote:
Originally Posted by vasava
@Tobi: Are rhoMin and rhoMax the value of minimum and maximum density from rhoCoeffs function respectively??

No. In the pEqn.H the solver calculates your density with your thermodynamic model. After that you bound your density with the values you insert in your fvSolution. That is helpful if you know that the density range of your fluid should be between 0.8 and 1 (or other values). If the thermodynamic calculates 0.001 and 3 in some cells it will be cutted and set to the values you set. That is very helpful if there are only some cells which give unphysical results. It stabilizes your solution BUT you should always check the output cutting is unphysical too. So if you set rhoMin to 0.5 and the solver calculate rhoMin = 0.43, you should decrease your rhoMin because 0.43 seems to be correct.

  • in this case here, jetfire just copy pasted the values out of a tutorial, but in his case it would be possible (due to pressure, temperature, velocity » 300.000 rpms) to get lower or higher densities like 0.5 and 2. Therefor I just setted some other values. You have to decide which values should be good.

    Example
    I am using and developing the flamelet solver (combustion model) and know that in my combustion the density only could be between 0.23 and 1.8. Therefor I change all cells which are not within these interval to this values.

    - its just an example because it will never happen in that solver
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