View Issue Details
ID | Project | Category | View Status | Date Submitted | Last Update |
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0000514 | OpenFOAM | Bug | public | 2012-04-18 04:22 | 2012-04-18 15:34 |
Reporter | Assigned To | henry | |||
Priority | normal | Severity | major | Reproducibility | sometimes |
Status | closed | Resolution | fixed | ||
Platform | Xeon Cluster | OS | CentOS | OS Version | 5.x |
Summary | 0000514: time step directory naming error | ||||
Description | Hi I have experienced naming error when time is over 1.0 sec. This is a copy from SSH terminal [c28li@saw-login1 naca0012_10_256d_v4_m2_s1]$ ls processor0 0.01 0.28 0.55 0.82 1.0900000000005896 1.3600000000023584 0.02 0.29 0.56 0.83 1.1000000000006551 1.3700000000024239 0.03 0.3 0.57 0.84 1.1100000000007206 1.3800000000024895 0.04 0.31 0.58 0.85 1.1200000000007861 1.390000000002555 0.05 0.32 0.59 0.86 1.1300000000008517 1.4000000000026205 0.06 0.33 0.6 0.87 1.1400000000009172 1.410000000002686 0.07 0.34 0.61 0.88 1.1500000000009827 1.4200000000027515 0.08 0.35 0.62 0.89 1.1600000000010482 1.430000000002817 0.09 0.36 0.63 0.9 1.1700000000011137 1.440000000003 0.1 0.37 0.64 0.91 1.1800000000011792 1.450000000003 0.11 0.38 0.65 0.92 1.1900000000012447 1.460000000003 0.12 0.39 0.66 0.93 1.2000000000013102 1.470000000003 0.13 0.4 0.67 0.94 1.2100000000013758 1.480000000003 0.14 0.41 0.68 0.95 1.2200000000014413 1.490000000003 0.15 0.42 0.69 0.96 1.2300000000015068 1.500000000003 0.16 0.43 0.7 0.97 1.2400000000015723 1.510000000003 0.17 0.44 0.71 0.98 1.2500000000016378 1.520000000003 0.18 0.45 0.72 0.99 1.2600000000017033 1.530000000003 0.19 0.46 0.73 1 1.2700000000017688 1.540000000004 0.2 0.47 0.74 1.0100000000000655 1.2800000000018343 1.550000000004 0.21 0.48 0.75 1.020000000000131 1.2900000000018998 1.560000000004 0.22 0.49 0.76 1.0300000000001965 1.3000000000019654 1.570000000004 0.23 0.5 0.77 1.040000000000262 1.3100000000020309 1.580000000004 0.24 0.51 0.78 1.0500000000003276 1.3200000000020964 1.590000000004 0.25 0.52 0.79 1.0600000000003931 1.3300000000021619 1.600000000004 0.26 0.53 0.8 1.0700000000004586 1.3400000000022274 constant 0.27 0.54 0.81 1.0800000000005241 1.3500000000022929 I am using ver 2.0.1 Attached is my controlDict Thank you very much for your time. Please let me know if additional info is needed. Best Regards, Tom | ||||
Steps To Reproduce | run simulation over 1.0 sec | ||||
Tags | No tags attached. | ||||
2012-04-18 04:22
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controlDict (2,312 bytes)
/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 2.0.1 | | \\ / A nd | Web: www.OpenFOAM.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class dictionary; location "system"; object controlDict; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // application pisoFoam; startFrom latestTime; startTime 1.0; stopAt endTime; endTime 3.0; deltaT 5e-6; writeControl runTime; writeInterval 0.01; purgeWrite 0; writeFormat ascii; writePrecision 6; writeCompression off; timeFormat general; timePrecision 6; runTimeModifiable true; maxCo 0.5; functions { forces { type forceCoeffs; functionObjectLibs ( "libforces.so" ); outputControl timeStep; outputInterval 1; patches ( AIRFOIL ); pName p; UName U; log true; rhoName rhoInf; rhoInf 1.2041; CofR ( 0 0 0 ); liftDir ( 0 1 0 ); dragDir ( 1 0 0 ); pitchAxis ( 0 0 1 ); magUInf 28.16; lRef 0.914; Aref 0.0835396; } /* wallPressure { type surfaces; functionObjectLibs ("libsampling.so"); outputControl timeStep; outputInterval 1; surfaceFormat foamFile; interpolationScheme cell; fields ( p ); surfaces ( AIRFOIL_WALL { type patch; patches (AIRFOIL); triangulate false; } ); } */ } // ************************************************************************* // |
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Hi, this is not a bug, but an incorrect setting in your controlDict. You are using an adaptive time-stepping with "writeControl runTime;". It should be "writeControl adjustableRunTime;". P.S. This is explained in the User's Guide ;-) |
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Hi Thanks for your reply. Sorry I am pretty new to openFOAM. I see in the guide it says the adjustableRunTime is used for cases with automatic time step adjustment. My question is, even if I don't have the line " adjustTimeStep yes;" does it still do the adjustment? Would it be better if I just turn it off by adding the line " adjustTimeStep no;" instead? Thanks for your time. Best Regards Tom |
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It should default to "false" if you do not have the line ( http://foam.sourceforge.net/docs/cpp/a03938_source.html#l00029 ), however you can check directly from your log file to see what the solver is actually doing. |
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Also, did you try to reproduce this problem with OpenFOAM 2.1.x? |
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Hi Thanks for your reply. When I check my log this appears after timestep 1.00001 Time = 1.00001 Courant Number mean: 0.00657961 max: 0.698939 DILUPBiCG: Solving for Ux, Initial residual = 4.53454e-06, Final residual = 4.53454e-06, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 9.47834e-06, Final residual = 9.47834e-06, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 6.56565e-06, Final residual = 6.56565e-06, No Iterations 0 DICPCG: Solving for p, Initial residual = 0.00490607, Final residual = 0.000453238, No Iterations 2 time step continuity errors : sum local = 3.65471e-10, global = 3.08417e-13, cumulative = 3.08417e-13 DICPCG: Solving for p, Initial residual = 0.00129323, Final residual = 9.6964e-07, No Iterations 393 time step continuity errors : sum local = 7.82084e-13, global = -2.91727e-15, cumulative = 3.055e-13 DILUPBiCG: Solving for omega, Initial residual = 6.14083e-06, Final residual = 6.14083e-06, No Iterations 0 DILUPBiCG: Solving for k, Initial residual = 8.174e-06, Final residual = 8.174e-06, No Iterations 0 ExecutionTime = 4.45 s ClockTime = 7 s forceCoeffs output: Cd = 0.0571562 Cl = -1.11777 Cm = -0.282938 --> FOAM Warning : From function Time::operator++() in file db/Time/Time.C at line 937 Increased the timePrecision from 6 to 17 to distinguish between timeNames at time 1.00001 Time = 1.0000100000000001 Courant Number mean: 0.00657961 max: 0.698938 DILUPBiCG: Solving for Ux, Initial residual = 4.76721e-06, Final residual = 4.76721e-06, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.00906e-05, Final residual = 5.20755e-10, No Iterations 1 DILUPBiCG: Solving for Uz, Initial residual = 1.80269e-05, Final residual = 1.4854e-09, No Iterations 1 DICPCG: Solving for p, Initial residual = 0.00600079, Final residual = 0.000381914, No Iterations 3 time step continuity errors : sum local = 3.0789e-10, global = 1.94607e-12, cumulative = 2.25157e-12 DICPCG: Solving for p, Initial residual = 0.00152424, Final residual = 9.95328e-07, No Iterations 405 time step continuity errors : sum local = 8.02255e-13, global = -2.4823e-15, cumulative = 2.24909e-12 DILUPBiCG: Solving for omega, Initial residual = 6.14084e-06, Final residual = 6.14084e-06, No Iterations 0 DILUPBiCG: Solving for k, Initial residual = 8.17437e-06, Final residual = 8.17437e-06, No Iterations 0 ExecutionTime = 5.3 s ClockTime = 8 s forceCoeffs output: Cd = 0.0572613 Cl = -1.11859 Cm = -0.283292 Is this change in time precision fixable by changing writeControl to adjustableRunTime? Btw I do not have OpenFOAM 2.1.x installed in the cluster (it takes a lot of work to get the support person to install a newer version). Thanks, Tom |
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Apparently your time-step changed from 1.0e-6 to 1.0e-17, if you compare the two times you reported. |
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It looks like your case is blowing-up and the time-step is too small to continue. |
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Sorry I went to bed last night and did not reply to the last note the time step actually went like this(copied from log) Time = 1.00001 Time = 1.0000100000000001 Time = 1.0000150000000001 Time = 1.0000200000000001 Time = 1.0000250000000002 Time = 1.0000300000000002 . . . my original timestep is set to be 5e-6 so it is not actually blowing up |
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Various aspects of time handling have been improved in OpenFOAM-2.1.0 and 2.1.x and it is likely that you will not see this problem if you run OpenFOAM-2.1.x. In anycase if there is a problem we need a bug-report for OpenFOAM-2.1.x as it is this version to which any patches would be applied. |
Date Modified | Username | Field | Change |
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2012-04-18 04:22 |
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New Issue | |
2012-04-18 04:22 |
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File Added: controlDict | |
2012-04-18 05:21 | albertop | Note Added: 0001264 | |
2012-04-18 05:32 |
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Note Added: 0001265 | |
2012-04-18 05:37 | albertop | Note Added: 0001266 | |
2012-04-18 05:38 | albertop | Note Added: 0001267 | |
2012-04-18 05:50 |
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Note Added: 0001268 | |
2012-04-18 06:00 | albertop | Note Added: 0001269 | |
2012-04-18 07:48 | henry | Note Added: 0001271 | |
2012-04-18 07:48 | henry | Status | new => closed |
2012-04-18 07:48 | henry | Assigned To | => henry |
2012-04-18 07:48 | henry | Resolution | open => fixed |
2012-04-18 15:28 |
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Note Added: 0001274 | |
2012-04-18 15:28 |
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Status | closed => feedback |
2012-04-18 15:28 |
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Resolution | fixed => reopened |
2012-04-18 15:34 | henry | Note Added: 0001275 | |
2012-04-18 15:34 | henry | Status | feedback => closed |
2012-04-18 15:34 | henry | Resolution | reopened => fixed |