Courant Number problem!
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Mukut
May 2, 2014, 8:00:34 AM5/2/14
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According to user guide (page: U22), cell size is the ratio of length of domain in velocity direction/number of cell. But in that tutorial both x and y direction have 10 cells but in my case in xy domain size is 60mmX20mm, Ux is 1m/s and total cell is NX=140 and NY=56. Can I use the rules as stated in U22 of user guide for my case?
According to U22 page: cell size is 60/(1000X140)=0.000428571m, so to maintain Co<1, deltaT must be 1X0.000428571/1=0.000428571s~0.0004s. I choose end time 0.1 if I want to write result in 0.01, 0.02.....interval then writeInterval should be 25. but after running icoFoam solver shows following error:
So, is there any other rule to calculate cell size to keep Co<1 for domain have uneven x and y direction size?
Thanks
According to U22 page: cell size is 60/(1000X140)=0.000428571m, so to maintain Co<1, deltaT must be 1X0.000428571/1=0.000428571s~0.0004s. I choose end time 0.1 if I want to write result in 0.01, 0.02.....interval then writeInterval should be 25. but after running icoFoam solver shows following error:
/*---------------------------------------------------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.2.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
Build : 2.2.1-57f3c3617a2d
Exec : icoFoam
Date : May 02 2014
Time : 17:11:56
Host : "mukut-Endeavor-MR3300"
PID : 3170
Case : /home/mukut/OpenFOAM/mukut-2.2.1/run/tutorials/2D_flow
nProcs : 1
sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE).
fileModificationChecking : Monitoring run-time modified files using timeStampMaster
allowSystemOperations : Disallowing user-supplied system call operations
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time
Create mesh for time = 0
// using new solver syntax:
p
{
solver PCG;
preconditioner DIC;
tolerance 1e-06;
relTol 0;
}
// using new solver syntax:
U
{
solver PBiCG;
preconditioner DILU;
tolerance 1e-05;
relTol 0;
}
Reading transportProperties
Reading field p
Reading field U
Reading/calculating face flux field phi
Starting time loop
Time = 0.0004
Courant Number mean: 0.00333403 max: 0.4
DILUPBiCG: Solving for Ux, Initial residual = 1, Final residual = 6.9902e-06, No Iterations 20
DILUPBiCG: Solving for Uy, Initial residual = 0, Final residual = 0, No Iterations 0
DICPCG: Solving for p, Initial residual = 1, Final residual = 8.3647e-07, No Iterations 126
time step continuity errors : sum local = 5.57763e-09, global = 2.36078e-11, cumulative = 2.36078e-11
DICPCG: Solving for p, Initial residual = 0.00365962, Final residual = 7.90978e-07, No Iterations 96
time step continuity errors : sum local = 2.04823e-06, global = -1.6356e-09, cumulative = -1.612e-09
ExecutionTime = 0.14 s ClockTime = 0 s
Time = 0.0008
Courant Number mean: 0.939677 max: 8.47515
DILUPBiCG: Solving for Ux, Initial residual = 0.117475, Final residual = 6.03513e-06, No Iterations 21
DILUPBiCG: Solving for Uy, Initial residual = 0.610455, Final residual = 7.05006e-06, No Iterations 22
DICPCG: Solving for p, Initial residual = 0.374522, Final residual = 8.77779e-07, No Iterations 116
time step continuity errors : sum local = 9.30842e-08, global = -6.57683e-10, cumulative = -2.26968e-09
DICPCG: Solving for p, Initial residual = 0.0109541, Final residual = 9.66365e-07, No Iterations 96
time step continuity errors : sum local = 3.63737e-06, global = -2.97477e-08, cumulative = -3.20174e-08
ExecutionTime = 0.21 s ClockTime = 0 s
Time = 0.0012
Courant Number mean: 1.03672 max: 11.4177
DILUPBiCG: Solving for Ux, Initial residual = 0.129339, Final residual = 7.04784e-06, No Iterations 21
DILUPBiCG: Solving for Uy, Initial residual = 0.710963, Final residual = 9.88029e-06, No Iterations 23
DICPCG: Solving for p, Initial residual = 0.766332, Final residual = 9.26548e-07, No Iterations 124
time step continuity errors : sum local = 1.661e-07, global = 2.3631e-09, cumulative = -2.96543e-08
DICPCG: Solving for p, Initial residual = 0.0825218, Final residual = 9.76701e-07, No Iterations 113
time step continuity errors : sum local = 2.95977e-06, global = -1.48726e-07, cumulative = -1.7838e-07
ExecutionTime = 0.29 s ClockTime = 0 s
Time = 0.0016
Courant Number mean: 1.02048 max: 66.756
DILUPBiCG: Solving for Ux, Initial residual = 0.308157, Final residual = 9.92223e-06, No Iterations 20
DILUPBiCG: Solving for Uy, Initial residual = 0.739007, Final residual = 8.1745e-06, No Iterations 24
DICPCG: Solving for p, Initial residual = 0.966796, Final residual = 8.21329e-07, No Iterations 124
time step continuity errors : sum local = 1.79897e-06, global = -1.47096e-08, cumulative = -1.9309e-07
DICPCG: Solving for p, Initial residual = 0.418352, Final residual = 7.38538e-07, No Iterations 115
time step continuity errors : sum local = 8.55004e-06, global = 2.44562e-07, cumulative = 5.14721e-08
ExecutionTime = 0.37 s ClockTime = 0 s
Time = 0.002
Courant Number mean: 3.1269 max: 929.773
DILUPBiCG: Solving for Ux, Initial residual = 0.671511, Final residual = 4.47676e-06, No Iterations 29
DILUPBiCG: Solving for Uy, Initial residual = 0.749109, Final residual = 6.56033e-06, No Iterations 29
DICPCG: Solving for p, Initial residual = 0.950235, Final residual = 8.76737e-07, No Iterations 124
time step continuity errors : sum local = 4.38934e-05, global = 1.45237e-08, cumulative = 6.59958e-08
DICPCG: Solving for p, Initial residual = 0.475735, Final residual = 8.64889e-07, No Iterations 115
time step continuity errors : sum local = 0.000200492, global = -8.13981e-06, cumulative = -8.07381e-06
ExecutionTime = 0.46 s ClockTime = 0 s
Time = 0.0024
Courant Number mean: 80.6568 max: 11121.7
DILUPBiCG: Solving for Ux, Initial residual = 0.853723, Final residual = 9.56755e-06, No Iterations 103
DILUPBiCG: Solving for Uy, Initial residual = 0.878405, Final residual = 9.46159e-06, No Iterations 103
DICPCG: Solving for p, Initial residual = 0.885602, Final residual = 9.10444e-07, No Iterations 124
time step continuity errors : sum local = 0.000677409, global = 2.4237e-05, cumulative = 1.61632e-05
DICPCG: Solving for p, Initial residual = 0.812741, Final residual = 8.64151e-07, No Iterations 92
time step continuity errors : sum local = 0.00940718, global = -0.000352984, cumulative = -0.00033682
ExecutionTime = 0.59 s ClockTime = 0 s
Time = 0.0028
Courant Number mean: 11385.4 max: 2.77749e+06
DILUPBiCG: Solving for Ux, Initial residual = 0.999751, Final residual = 5.02601, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.999936, Final residual = 126.958, No Iterations 1001
DICPCG: Solving for p, Initial residual = 0.999999, Final residual = 8.30573e-07, No Iterations 350
time step continuity errors : sum local = 8598.34, global = -559.518, cumulative = -559.518
DICPCG: Solving for p, Initial residual = 0.999723, Final residual = 5.83105e-07, No Iterations 371
time step continuity errors : sum local = 2.5578e+07, global = -1.59844e+06, cumulative = -1.599e+06
ExecutionTime = 1.5 s ClockTime = 1 s
Time = 0.0032
Courant Number mean: 4.92716e+13 max: 2.9337e+16
DILUPBiCG: Solving for Ux, Initial residual = 1, Final residual = 6.23813, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 1, Final residual = 1.59548, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 0.687954, No Iterations 1001
time step continuity errors : sum local = 1.43637e+23, global = 1.2921e+16, cumulative = 1.2921e+16
DICPCG: Solving for p, Initial residual = 1, Final residual = 13.9379, No Iterations 1001
time step continuity errors : sum local = 6.59092e+32, global = -4.75049e+26, cumulative = -4.75049e+26
ExecutionTime = 2.68 s ClockTime = 2 s
Time = 0.0036
Courant Number mean: 1.37306e+33 max: 4.20542e+35
DILUPBiCG: Solving for Ux, Initial residual = 0.998483, Final residual = 7.98361, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.998625, Final residual = 5.6728, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 106.682, No Iterations 1001
time step continuity errors : sum local = 4.60012e+39, global = -5.37472e+36, cumulative = -5.37472e+36
DICPCG: Solving for p, Initial residual = 0.685801, Final residual = 6.81219, No Iterations 1001
time step continuity errors : sum local = 1.86666e+42, global = 1.09782e+40, cumulative = 1.09728e+40
ExecutionTime = 3.84 s ClockTime = 4 s
Time = 0.004
Courant Number mean: 4.23292e+42 max: 2.85131e+45
DILUPBiCG: Solving for Ux, Initial residual = 0.99987, Final residual = 5.69238, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.999624, Final residual = 4.53821, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 0.749635, No Iterations 1001
time step continuity errors : sum local = 5.49266e+48, global = -3.23794e+44, cumulative = -3.23783e+44
DICPCG: Solving for p, Initial residual = 0.995326, Final residual = 2.97407, No Iterations 1001
time step continuity errors : sum local = 1.99896e+51, global = 7.4343e+47, cumulative = 7.43106e+47
ExecutionTime = 5 s ClockTime = 5 s
Time = 0.0044
Courant Number mean: 4.32551e+51 max: 5.65048e+54
DILUPBiCG: Solving for Ux, Initial residual = 0.999896, Final residual = 502274, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.999307, Final residual = 44.6582, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 1.53482, No Iterations 1001
time step continuity errors : sum local = 5.0944e+62, global = -2.86608e+59, cumulative = -2.86608e+59
DICPCG: Solving for p, Initial residual = 0.989688, Final residual = 1.22825, No Iterations 1001
time step continuity errors : sum local = 9.8738e+64, global = 8.55211e+61, cumulative = 8.52345e+61
ExecutionTime = 6.18 s ClockTime = 6 s
Time = 0.0048
Courant Number mean: 2.11114e+65 max: 1.04058e+68
DILUPBiCG: Solving for Ux, Initial residual = 0.997635, Final residual = 61.2412, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.998542, Final residual = 4.35875, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 389.826, No Iterations 1001
time step continuity errors : sum local = 7.61063e+73, global = -6.18308e+70, cumulative = -6.18308e+70
DICPCG: Solving for p, Initial residual = 0.963431, Final residual = 4.65799, No Iterations 1001
time step continuity errors : sum local = 9.68852e+76, global = -1.44465e+73, cumulative = -1.45083e+73
ExecutionTime = 7.34 s ClockTime = 7 s
Time = 0.0052
Courant Number mean: 2.02508e+77 max: 2.69073e+80
DILUPBiCG: Solving for Ux, Initial residual = 0.999243, Final residual = 22.0185, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.999, Final residual = 4.35926, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 1.19302, No Iterations 1001
time step continuity errors : sum local = 1.27422e+83, global = 3.72682e+79, cumulative = 3.72681e+79
DICPCG: Solving for p, Initial residual = 0.99403, Final residual = 1.65487, No Iterations 1001
time step continuity errors : sum local = 8.0513e+85, global = 1.34128e+81, cumulative = 1.37855e+81
ExecutionTime = 8.54 s ClockTime = 8 s
Time = 0.0056
Courant Number mean: 1.36321e+86 max: 3.91825e+89
DILUPBiCG: Solving for Ux, Initial residual = 0.99893, Final residual = 7.39751, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.999934, Final residual = 5.0877, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 9.44171, No Iterations 1001
time step continuity errors : sum local = 2.05036e+92, global = -6.48639e+89, cumulative = -6.48639e+89
DICPCG: Solving for p, Initial residual = 0.90806, Final residual = 1.89116, No Iterations 1001
time step continuity errors : sum local = 3.84589e+94, global = -1.50046e+91, cumulative = -1.56532e+91
ExecutionTime = 9.7 s ClockTime = 9 s
Time = 0.006
Courant Number mean: 8.36046e+94 max: 8.29096e+97
DILUPBiCG: Solving for Ux, Initial residual = 0.99973, Final residual = 5.30467, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.998497, Final residual = 16.6269, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 3.01526, No Iterations 1001
time step continuity errors : sum local = 2.29046e+100, global = 2.77947e+96, cumulative = 2.77945e+96
#0 Foam::error::printStack(Foam::Ostream&) in "/opt/openfoam221/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#1 Foam::sigFpe::sigHandler(int) in "/opt/openfoam221/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#2 in "/lib/x86_64-linux-gnu/libc.so.6"
#3 double Foam::sumProd<double>(Foam::UList<double> const&, Foam::UList<double> const&) in "/opt/openfoam221/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#4 Foam::PCG::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const in "/opt/openfoam221/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#5 Foam::fvMatrix<double>::solveSegregated(Foam::dictionary const&) in "/opt/openfoam221/platforms/linux64GccDPOpt/lib/libfiniteVolume.so"
#6 Foam::fvMatrix<double>::solve(Foam::dictionary const&) in "/opt/openfoam221/platforms/linux64GccDPOpt/bin/icoFoam"
#7
at icoFoam.C:0
#8
in "/opt/openfoam221/platforms/linux64GccDPOpt/bin/icoFoam"
#9 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#10
in "/opt/openfoam221/platforms/linux64GccDPOpt/bin/icoFoam"
Floating point exception (core dumped)
So, is there any other rule to calculate cell size to keep Co<1 for domain have uneven x and y direction size?
Thanks
Mukut
May 4, 2014, 12:58:23 AM5/4/14
to open...@googlegroups.com
Anybody help me please! How can I keep Co<1 here :(
What is the rule to keep Co<1, if the domain is consist of multiple blocks?
What is the rule to keep Co<1, if the domain is consist of multiple blocks?
大渕真志
May 4, 2014, 5:32:46 AM5/4/14
to OpenFOAM
Hi, Mukut,
For the auto time step control feature, please check and see
"U-60 2.3.6 Time step control" in UserGuide.
adjustTimeStep yes; // switch for auto time stepping feature
maxCo 1.0; // maximum Courant Number
maxDeltaT 0.01; // maximum time step in sec.
Best,
Masashi Obuchi
2014-05-04 6:58 GMT+02:00 Mukut <engr...@gmail.com>:
Anybody help me please! How can I keep Co<1 here :(
What is the rule to keep Co<1, if the domain is consist of multiple blocks?
--
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Mukut
May 4, 2014, 11:53:08 PM5/4/14
to open...@googlegroups.com
Dear Obuchi san,
Good morning. I have followed your instruction. This is the controlDict:
Good morning. I have followed your instruction. This is the controlDict:
/*---------------------------------------------------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 1.0 |
| \\ / A nd | Web: http://www.openfoam.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
root "";
case "";
instance "";
local "";
class dictionary;
object controlDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
application icoFoam;
startFrom startTime;
startTime 0;
stopAt endTime;
endTime 0.1;
deltaT 0.0004;
writeControl adjustableRunTime;
writeInterval 25;
purgeWrite 0;
writeFormat ascii;
writePrecision 6;
writeCompression uncompressed;
timeFormat general;
timePrecision 6;
runTimeModifiable yes;
adjustTimeStep yes;
maxCo 1.0;
maxDeltaT 0.01;
// ************************************************************************* //
Mukut
May 4, 2014, 11:54:29 PM5/4/14
to open...@googlegroups.com
But still C0 is increasing.....I have attached the terminal text:
/*---------------------------------------------------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.2.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
Build : 2.2.1-57f3c3617a2d
Exec : icoFoam
Date : May 05 2014
Time : 09:41:30
Host : "mukut-Endeavor-MR3300"
PID : 3903
Case : /home/mukut/OpenFOAM/mukut-2.2.1/run/tutorials/2D_flow
nProcs : 1
sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE).
fileModificationChecking : Monitoring run-time modified files using timeStampMaster
allowSystemOperations : Disallowing user-supplied system call operations
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
ExecutionTime = 0.22 s ClockTime = 0 s
Time = 0.0012
Courant Number mean: 1.03672 max: 11.4177
DILUPBiCG: Solving for Ux, Initial residual = 0.129339, Final residual = 7.04784e-06, No Iterations 21
DILUPBiCG: Solving for Uy, Initial residual = 0.710963, Final residual = 9.88029e-06, No Iterations 23
DICPCG: Solving for p, Initial residual = 0.766332, Final residual = 9.26548e-07, No Iterations 124
time step continuity errors : sum local = 1.661e-07, global = 2.3631e-09, cumulative = -2.96543e-08
DICPCG: Solving for p, Initial residual = 0.0825218, Final residual = 9.76701e-07, No Iterations 113
time step continuity errors : sum local = 2.95977e-06, global = -1.48726e-07, cumulative = -1.7838e-07
ExecutionTime = 0.3 s ClockTime = 0 s
Time = 0.0016
Courant Number mean: 1.02048 max: 66.756
DILUPBiCG: Solving for Ux, Initial residual = 0.308157, Final residual = 9.92223e-06, No Iterations 20
DILUPBiCG: Solving for Uy, Initial residual = 0.739007, Final residual = 8.1745e-06, No Iterations 24
DICPCG: Solving for p, Initial residual = 0.966796, Final residual = 8.21329e-07, No Iterations 124
time step continuity errors : sum local = 1.79897e-06, global = -1.47096e-08, cumulative = -1.9309e-07
DICPCG: Solving for p, Initial residual = 0.418352, Final residual = 7.38538e-07, No Iterations 115
time step continuity errors : sum local = 8.55004e-06, global = 2.44562e-07, cumulative = 5.14721e-08
ExecutionTime = 0.38 s ClockTime = 0 s
Time = 0.002
Courant Number mean: 3.1269 max: 929.773
DILUPBiCG: Solving for Ux, Initial residual = 0.671511, Final residual = 4.47676e-06, No Iterations 29
DILUPBiCG: Solving for Uy, Initial residual = 0.749109, Final residual = 6.56033e-06, No Iterations 29
DICPCG: Solving for p, Initial residual = 0.950235, Final residual = 8.76737e-07, No Iterations 124
time step continuity errors : sum local = 4.38934e-05, global = 1.45237e-08, cumulative = 6.59958e-08
DICPCG: Solving for p, Initial residual = 0.475735, Final residual = 8.64889e-07, No Iterations 115
time step continuity errors : sum local = 0.000200492, global = -8.13981e-06, cumulative = -8.07381e-06
ExecutionTime = 0.46 s ClockTime = 0 s
Time = 0.0024
Courant Number mean: 80.6568 max: 11121.7
DILUPBiCG: Solving for Ux, Initial residual = 0.853723, Final residual = 9.56755e-06, No Iterations 103
DILUPBiCG: Solving for Uy, Initial residual = 0.878405, Final residual = 9.46159e-06, No Iterations 103
DICPCG: Solving for p, Initial residual = 0.885602, Final residual = 9.10444e-07, No Iterations 124
time step continuity errors : sum local = 0.000677409, global = 2.4237e-05, cumulative = 1.61632e-05
DICPCG: Solving for p, Initial residual = 0.812741, Final residual = 8.64151e-07, No Iterations 92
time step continuity errors : sum local = 0.00940718, global = -0.000352984, cumulative = -0.00033682
ExecutionTime = 0.6 s ClockTime = 0 s
Time = 0.0028
Courant Number mean: 11385.4 max: 2.77749e+06
DILUPBiCG: Solving for Ux, Initial residual = 0.999751, Final residual = 5.02601, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.999936, Final residual = 126.958, No Iterations 1001
DICPCG: Solving for p, Initial residual = 0.999999, Final residual = 8.30573e-07, No Iterations 350
time step continuity errors : sum local = 8598.34, global = -559.518, cumulative = -559.518
DICPCG: Solving for p, Initial residual = 0.999723, Final residual = 5.83105e-07, No Iterations 371
time step continuity errors : sum local = 2.5578e+07, global = -1.59844e+06, cumulative = -1.599e+06
ExecutionTime = 1.51 s ClockTime = 1 s
Time = 0.0032
Courant Number mean: 4.92716e+13 max: 2.9337e+16
DILUPBiCG: Solving for Ux, Initial residual = 1, Final residual = 6.23813, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 1, Final residual = 1.59548, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 0.687954, No Iterations 1001
time step continuity errors : sum local = 1.43637e+23, global = 1.2921e+16, cumulative = 1.2921e+16
DICPCG: Solving for p, Initial residual = 1, Final residual = 13.9379, No Iterations 1001
time step continuity errors : sum local = 6.59092e+32, global = -4.75049e+26, cumulative = -4.75049e+26
ExecutionTime = 2.68 s ClockTime = 3 s
Time = 0.0036
Courant Number mean: 1.37306e+33 max: 4.20542e+35
DILUPBiCG: Solving for Ux, Initial residual = 0.998483, Final residual = 7.98361, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.998625, Final residual = 5.6728, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 106.682, No Iterations 1001
time step continuity errors : sum local = 4.60012e+39, global = -5.37472e+36, cumulative = -5.37472e+36
DICPCG: Solving for p, Initial residual = 0.685801, Final residual = 6.81219, No Iterations 1001
time step continuity errors : sum local = 1.86666e+42, global = 1.09782e+40, cumulative = 1.09728e+40
ExecutionTime = 3.84 s ClockTime = 4 s
Time = 0.004
Courant Number mean: 4.23292e+42 max: 2.85131e+45
DILUPBiCG: Solving for Ux, Initial residual = 0.99987, Final residual = 5.69238, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.999624, Final residual = 4.53821, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 0.749635, No Iterations 1001
time step continuity errors : sum local = 5.49266e+48, global = -3.23794e+44, cumulative = -3.23783e+44
DICPCG: Solving for p, Initial residual = 0.995326, Final residual = 2.97407, No Iterations 1001
time step continuity errors : sum local = 1.99896e+51, global = 7.4343e+47, cumulative = 7.43106e+47
ExecutionTime = 5.01 s ClockTime = 5 s
Time = 0.0044
Courant Number mean: 4.32551e+51 max: 5.65048e+54
DILUPBiCG: Solving for Ux, Initial residual = 0.999896, Final residual = 502274, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.999307, Final residual = 44.6582, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 1.53482, No Iterations 1001
time step continuity errors : sum local = 5.0944e+62, global = -2.86608e+59, cumulative = -2.86608e+59
DICPCG: Solving for p, Initial residual = 0.989688, Final residual = 1.22825, No Iterations 1001
time step continuity errors : sum local = 9.8738e+64, global = 8.55211e+61, cumulative = 8.52345e+61
ExecutionTime = 6.19 s ClockTime = 6 s
Time = 0.0048
Courant Number mean: 2.11114e+65 max: 1.04058e+68
DILUPBiCG: Solving for Ux, Initial residual = 0.997635, Final residual = 61.2412, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.998542, Final residual = 4.35875, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 389.826, No Iterations 1001
time step continuity errors : sum local = 7.61063e+73, global = -6.18308e+70, cumulative = -6.18308e+70
DICPCG: Solving for p, Initial residual = 0.963431, Final residual = 4.65799, No Iterations 1001
time step continuity errors : sum local = 9.68852e+76, global = -1.44465e+73, cumulative = -1.45083e+73
ExecutionTime = 7.35 s ClockTime = 7 s
Time = 0.0052
Courant Number mean: 2.02508e+77 max: 2.69073e+80
DILUPBiCG: Solving for Ux, Initial residual = 0.999243, Final residual = 22.0185, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.999, Final residual = 4.35926, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 1.19302, No Iterations 1001
time step continuity errors : sum local = 1.27422e+83, global = 3.72682e+79, cumulative = 3.72681e+79
DICPCG: Solving for p, Initial residual = 0.99403, Final residual = 1.65487, No Iterations 1001
time step continuity errors : sum local = 8.0513e+85, global = 1.34128e+81, cumulative = 1.37855e+81
ExecutionTime = 8.54 s ClockTime = 8 s
Time = 0.0056
Courant Number mean: 1.36321e+86 max: 3.91825e+89
DILUPBiCG: Solving for Ux, Initial residual = 0.99893, Final residual = 7.39751, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.999934, Final residual = 5.0877, No Iterations 1001
DICPCG: Solving for p, Initial residual = 1, Final residual = 9.44171, No Iterations 1001
time step continuity errors : sum local = 2.05036e+92, global = -6.48639e+89, cumulative = -6.48639e+89
DICPCG: Solving for p, Initial residual = 0.90806, Final residual = 1.89116, No Iterations 1001
time step continuity errors : sum local = 3.84589e+94, global = -1.50046e+91, cumulative = -1.56532e+91
ExecutionTime = 9.7 s ClockTime = 10 s
大渕真志
May 5, 2014, 12:28:51 AM5/5/14
to OpenFOAM
Hi, Mukut,
Oh, you are using icoFoam!
Sorry. The solver "icoFoam" does not support auto time step control feature.
Please try to use "pisoFoam" or "pimpleFoam" instead.
Best
Masashi Obuchi
Mukut
May 5, 2014, 5:33:09 AM5/5/14
to open...@googlegroups.com
Dear Obuchi san,
Thanks for your information. Actually I started a incompressible laminar simple 2D flow problem. I will check with pisoFoam in this case I have to add transportporperties. I will inform soon about that. But is there anyway to reduce Co number in case of using icoFoam?
here is the blockmesh file:
Thanks for your information. Actually I started a incompressible laminar simple 2D flow problem. I will check with pisoFoam in this case I have to add transportporperties. I will inform soon about that. But is there anyway to reduce Co number in case of using icoFoam?
here is the blockmesh file:
/*---------------------------------------------------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 1.0 |
| \\ / A nd | Web: http://www.openfoam.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
root "";
case "";
instance "";
local "";
class dictionary;
object blockMeshDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
convertToMeters 0.001;
vertices
(
(0 0 0)
(2 0 0)
(7 0 0)
(10 0 0)
(40 0 0)
(-20 0 0)
(0 0.05 0)
(2 0.05 0)
(7 0.05 0)
(10 0.05 0)
(40 0.05 0)
(-20 0.05 0)
(0 0.25 0)
(2 0.25 0)
(7 0.25 0)
(10 0.25 0)
(40 0.25 0)
(-20 0.25 0)
(0 0.35 0)
(2 0.35 0)
(7 0.35 0)
(10 0.35 0)
(40 0.35 0)
(-20 0.35 0)
(0 20 0)
(2 20 0)
(7 20 0)
(10 20 0)
(40 20 0)
(-20 20 0)
(0 0 100)
(2 0 100)
(7 0 100)
(10 0 100)
(40 0 100)
(-20 0 100)
(0 0.05 100)
(2 0.05 100)
(7 0.05 100)
(10 0.05 100)
(40 0.05 100)
(-20 0.05 100)
(0 0.25 100)
(2 0.25 100)
(7 0.25 100)
(10 0.25 100)
(40 0.25 100)
(-20 0.25 100)
(0 0.35 100)
(2 0.35 100)
(7 0.35 100)
(10 0.35 100)
(40 0.35 100)
(-20 0.35 100)
(0 20 100)
(2 20 100)
(7 20 100)
(10 20 100)
(40 20 100)
(-20 20 100)
);
blocks
(
hex (5 0 6 11 35 30 36 41) (40 2 1) simpleGrading (1 1 1)
hex (0 1 7 6 30 31 37 36) (8 2 1) simpleGrading (1 1 1)
hex (2 3 9 8 32 33 39 38) (12 2 1) simpleGrading (1 1 1)
hex (3 4 10 9 33 34 40 39) (60 2 1) simpleGrading (1 1 1)
hex (11 6 12 17 41 36 42 47) (40 10 1) simpleGrading (1 1 1)
hex (6 7 13 12 36 37 43 42) (8 10 1) simpleGrading (1 1 1)
hex (7 8 14 13 37 38 44 43) (20 10 1) simpleGrading (1 1 1)
hex (8 9 15 14 38 39 45 44) (12 10 1) simpleGrading (1 1 1)
hex (9 10 16 15 39 40 46 45) (60 10 1) simpleGrading (1 1 1)
hex (17 12 18 23 47 42 48 53) (40 4 1) simpleGrading (1 1 1)
hex (12 13 19 18 42 43 49 48) (8 4 1) simpleGrading (1 1 1)
hex (13 14 20 19 43 44 50 49) (20 4 1) simpleGrading (1 1 1)
hex (14 15 21 20 44 45 51 50) (12 4 1) simpleGrading (1 1 1)
hex (15 16 22 21 45 46 52 51) (60 4 1) simpleGrading (1 1 1)
hex (23 18 24 29 53 48 54 59) (40 40 1) simpleGrading (1 1 1)
hex (18 19 25 24 48 49 55 54) (8 40 1) simpleGrading (1 1 1)
hex (19 20 26 25 49 50 56 55) (20 40 1) simpleGrading (1 1 1)
hex (20 21 27 26 50 51 57 56) (12 40 1) simpleGrading (1 1 1)
hex (21 22 28 27 51 52 58 57) (60 40 1) simpleGrading (1 1 1)
);
edges
(
);
patches
(
wall topWall
(
(29 59 54 24)
(24 54 55 25)
(25 55 56 26)
(26 56 57 27)
(27 57 58 28)
)
wall bottomWall
(
(5 0 30 35)
(0 1 31 30)
(1 7 37 31)
(7 8 38 37)
(2 32 38 8)
(2 3 33 32)
(3 4 34 33)
)
wall inlet
(
(5 35 41 11)
(11 41 47 17)
(17 47 53 23)
(23 53 59 29)
)
wall outlet
(
(10 40 34 4)
(16 46 40 10)
(22 52 46 16)
(28 58 52 22)
)
empty frontAndBack
(
(5 11 6 0)
(0 6 7 1)
(2 8 9 3)
(3 9 10 4)
(11 17 12 6)
(6 12 13 7)
(7 13 14 8)
(8 14 15 9)
(9 15 16 10)
(17 23 18 12)
(12 18 19 13)
(13 19 20 14)
(14 20 21 15)
(15 21 22 16)
(23 29 24 18)
(18 24 25 19)
(19 25 26 20)
(20 26 27 21)
(21 27 28 22)
(35 30 36 41)
(30 31 37 36)
(32 33 39 38)
(33 34 40 39)
(41 36 42 47)
(36 37 43 42)
(37 38 44 43)
(38 39 45 44)
(39 40 46 45)
(47 42 48 53)
(42 43 49 48)
(43 44 50 49)
(44 45 51 50)
(45 46 52 51)
(53 48 54 59)
(48 49 55 54)
(49 50 56 55)
(50 51 57 56)
(51 52 58 57)
)
);
mergePatchPairs
(
);
// ************************************************************************* //
大渕真志
May 5, 2014, 8:03:44 AM5/5/14
to OpenFOAM
Hi, Mukut,
I think there are two ways for improving your problem.
1. Making custom solver based on icoFoam with adopting auto time step control feature.
Insert following lines after #include "initContinuityErrs.H"
#include "readTimeControls.H"
#include "setDeltaT.H"2. Defining more appropriate initial condition via pitentialFoam or simpleFoam.
Best
Masashi Obuchi
Nidhin Kakkanattu
Sep 29, 2018, 12:49:41 AM9/29/18
to OpenFOAM
Hello Mukut
Did you find the solution to this problem? Because I am facing the same issue trying to solve for the last couple of days.
NIdhin Kakkanattu
Nidhin Kakkanattu
Sep 29, 2018, 5:31:52 AM9/29/18
to open...@googlegroups.com
Hello Bro
Yes i can help you in this. 9037324531 this is my whats app number. just message me bro.
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