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- - **Extrusion with OpenFoam problem No. Iterations 0**
(*http://www.cfd-online.com/Forums/openfoam/87126-extrusion-openfoam-problem-no-iterations-0-a.html*)

Extrusion with OpenFoam problem No. Iterations 0Hi, I'm trying to simulate a laminar flow in a cylinder (hole of the extrusion die) with inlet and outlet (bases) and wall (lateral). I modeled it with Salome 5 (CAE linux) and exported the mesh in UNV.
I post the files: RaspProperties/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 1.7.0 | | \\ / A nd | Web: www.OpenFOAM.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class dictionary; location "constant"; object RASProperties; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // RASModel laminar; turbulence off; printCoeffs on; // ************************************************** *********************** // transportProperties/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 1.7.0 | | \\ / A nd | Web: www.OpenFOAM.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class dictionary; location "constant"; object transportProperties; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // transportModel powerLaw; nu nu [ 0 2 -1 0 0 0 0 ] 1e-05; powerLawCoeffs { k k [0 2 -1 0 0 0 0] 2800; n n [0 0 0 0 0 0 0] 0.4; nuMin nuMin [0 2 -1 0 0 0 0] .1; nuMax nuMax [0 2 -1 0 0 0 0] 1000000; } CrossPowerLawCoeffs { nu0 nu0 [ 0 2 -1 0 0 0 0 ] 1e-06; nuInf nuInf [ 0 2 -1 0 0 0 0 ] 1e-06; m m [ 0 0 1 0 0 0 0 ] 1; n n [ 0 0 0 0 0 0 0 ] 1; } BirdCarreauCoeffs { nu0 nu0 [ 0 2 -1 0 0 0 0 ] 1e-06; nuInf nuInf [ 0 2 -1 0 0 0 0 ] 1e-06; k k [ 0 0 1 0 0 0 0 ] 0; n n [ 0 0 0 0 0 0 0 ] 1; } // ************************************************** *********************** // p/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 1.7.0 | | \\ / A nd | Web: www.OpenFOAM.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class volScalarField; object p; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 2 -2 0 0 0 0]; internalField uniform 0; boundaryField { inlet { type zeroGradient; } outlet { type fixedValue; value uniform 0; } wall { type zeroGradient; } } // ************************************************** *********************** // U/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 1.7.0 | | \\ / A nd | Web: www.OpenFOAM.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class volVectorField; object U; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 1 -1 0 0 0 0]; internalField uniform (0 0 0); boundaryField { inlet { type fixedValue; value uniform (.016 0 0); } outlet { type zeroGradient; } wall { type fixedValue; value uniform (0 0 0); } } // ************************************************** *********************** // fvSchemes/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 1.7.0 | | \\ / A nd | Web: www.OpenFOAM.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class dictionary; location "system"; object fvSchemes; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // ddtSchemes { default Euler; } gradSchemes { default Gauss linear; grad(p) Gauss linear; grad(U) Gauss linear; } divSchemes { default none; div(phi,U) Gauss upwind; div(phi,k) Gauss upwind; div(phi,epsilon) Gauss upwind; div(phi,R) Gauss upwind; div(R) Gauss linear; div(phi,nuTilda) Gauss upwind; div((nuEff*dev(grad(U).T()))) Gauss linear; } laplacianSchemes { default none; laplacian(nuEff,U) Gauss linear corrected; laplacian((1|A(U)),p) Gauss linear corrected; laplacian(DkEff,k) Gauss linear corrected; laplacian(DepsilonEff,epsilon) Gauss linear corrected; laplacian(DREff,R) Gauss linear corrected; laplacian(DnuTildaEff,nuTilda) Gauss linear corrected; } interpolationSchemes { default linear; interpolate(U) linear; } snGradSchemes { default corrected; } fluxRequired { default no; p ; } // ************************************************** *********************** // then I run simpleFoam in the directory of the simulation that I created and this is the results:[...............] Time = 979 DILUPBiCG: Solving for Ux, Initial residual = 1.23786e-16, Final residual = 1.23786e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.12365e-16, Final residual = 1.12365e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.22862e-16, Final residual = 1.22862e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30448e-08 ExecutionTime = 4.93 s ClockTime = 9 s Time = 980 DILUPBiCG: Solving for Ux, Initial residual = 1.26725e-16, Final residual = 1.26725e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.12963e-16, Final residual = 1.12963e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.21408e-16, Final residual = 1.21408e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30457e-08 ExecutionTime = 4.94 s ClockTime = 9 s Time = 981 DILUPBiCG: Solving for Ux, Initial residual = 1.23068e-16, Final residual = 1.23068e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.11831e-16, Final residual = 1.11831e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.23645e-16, Final residual = 1.23645e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30465e-08 ExecutionTime = 4.94 s ClockTime = 9 s Time = 982 DILUPBiCG: Solving for Ux, Initial residual = 1.26931e-16, Final residual = 1.26931e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.0935e-16, Final residual = 1.0935e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.22962e-16, Final residual = 1.22962e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30474e-08 ExecutionTime = 4.95 s ClockTime = 9 s Time = 983 DILUPBiCG: Solving for Ux, Initial residual = 1.23579e-16, Final residual = 1.23579e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.15394e-16, Final residual = 1.15394e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.2132e-16, Final residual = 1.2132e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30483e-08 ExecutionTime = 4.96 s ClockTime = 9 s Time = 984 DILUPBiCG: Solving for Ux, Initial residual = 1.26194e-16, Final residual = 1.26194e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.08941e-16, Final residual = 1.08941e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.23718e-16, Final residual = 1.23718e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30491e-08 ExecutionTime = 4.96 s ClockTime = 9 s Time = 985 DILUPBiCG: Solving for Ux, Initial residual = 1.23803e-16, Final residual = 1.23803e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.12121e-16, Final residual = 1.12121e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.22867e-16, Final residual = 1.22867e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.305e-08 ExecutionTime = 4.96 s ClockTime = 9 s Time = 986 DILUPBiCG: Solving for Ux, Initial residual = 1.26728e-16, Final residual = 1.26728e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.12798e-16, Final residual = 1.12798e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.21437e-16, Final residual = 1.21437e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30508e-08 ExecutionTime = 4.96 s ClockTime = 9 s Time = 987 DILUPBiCG: Solving for Ux, Initial residual = 1.23051e-16, Final residual = 1.23051e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.11958e-16, Final residual = 1.11958e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.23644e-16, Final residual = 1.23644e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30517e-08 ExecutionTime = 4.97 s ClockTime = 9 s Time = 988 DILUPBiCG: Solving for Ux, Initial residual = 1.26928e-16, Final residual = 1.26928e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.09385e-16, Final residual = 1.09385e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.22949e-16, Final residual = 1.22949e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30525e-08 ExecutionTime = 4.98 s ClockTime = 9 s Time = 989 DILUPBiCG: Solving for Ux, Initial residual = 1.23595e-16, Final residual = 1.23595e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.15446e-16, Final residual = 1.15446e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.21323e-16, Final residual = 1.21323e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30534e-08 ExecutionTime = 4.98 s ClockTime = 9 s Time = 990 DILUPBiCG: Solving for Ux, Initial residual = 1.26196e-16, Final residual = 1.26196e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.08924e-16, Final residual = 1.08924e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.23746e-16, Final residual = 1.23746e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30542e-08 ExecutionTime = 4.98 s ClockTime = 9 s Time = 991 DILUPBiCG: Solving for Ux, Initial residual = 1.23788e-16, Final residual = 1.23788e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.12266e-16, Final residual = 1.12266e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.22859e-16, Final residual = 1.22859e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30551e-08 ExecutionTime = 4.98 s ClockTime = 9 s Time = 992 DILUPBiCG: Solving for Ux, Initial residual = 1.26728e-16, Final residual = 1.26728e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.1293e-16, Final residual = 1.1293e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.21393e-16, Final residual = 1.21393e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30559e-08 ExecutionTime = 4.99 s ClockTime = 9 s Time = 993 DILUPBiCG: Solving for Ux, Initial residual = 1.23065e-16, Final residual = 1.23065e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.11725e-16, Final residual = 1.11725e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.23649e-16, Final residual = 1.23649e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30568e-08 ExecutionTime = 5 s ClockTime = 9 s Time = 994 DILUPBiCG: Solving for Ux, Initial residual = 1.26933e-16, Final residual = 1.26933e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.09154e-16, Final residual = 1.09154e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.22979e-16, Final residual = 1.22979e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30576e-08 ExecutionTime = 5 s ClockTime = 9 s Time = 995 DILUPBiCG: Solving for Ux, Initial residual = 1.23577e-16, Final residual = 1.23577e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.15583e-16, Final residual = 1.15583e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.21322e-16, Final residual = 1.21322e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30585e-08 ExecutionTime = 5.01 s ClockTime = 9 s Time = 996 DILUPBiCG: Solving for Ux, Initial residual = 1.26195e-16, Final residual = 1.26195e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.09024e-16, Final residual = 1.09024e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.2373e-16, Final residual = 1.2373e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30593e-08 ExecutionTime = 5.02 s ClockTime = 9 s Time = 997 DILUPBiCG: Solving for Ux, Initial residual = 1.23799e-16, Final residual = 1.23799e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.12231e-16, Final residual = 1.12231e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.22866e-16, Final residual = 1.22866e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30602e-08 ExecutionTime = 5.02 s ClockTime = 9 s Time = 998 DILUPBiCG: Solving for Ux, Initial residual = 1.2673e-16, Final residual = 1.2673e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.12967e-16, Final residual = 1.12967e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.21424e-16, Final residual = 1.21424e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.3061e-08 ExecutionTime = 5.03 s ClockTime = 9 s Time = 999 DILUPBiCG: Solving for Ux, Initial residual = 1.23049e-16, Final residual = 1.23049e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.11804e-16, Final residual = 1.11804e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.2364e-16, Final residual = 1.2364e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30619e-08 ExecutionTime = 5.03 s ClockTime = 9 s Time = 1000 DILUPBiCG: Solving for Ux, Initial residual = 1.26929e-16, Final residual = 1.26929e-16, No Iterations 0 DILUPBiCG: Solving for Uy, Initial residual = 1.09316e-16, Final residual = 1.09316e-16, No Iterations 0 DILUPBiCG: Solving for Uz, Initial residual = 1.22938e-16, Final residual = 1.22938e-16, No Iterations 0 DICPCG: Solving for p, Initial residual = 7.10497e-07, Final residual = 7.10497e-07, No Iterations 0 time step continuity errors : sum local = 3.29168e-12, global = -8.50298e-13, cumulative = -1.30627e-08 ExecutionTime = 5.05 s ClockTime = 10 s End I can't find the problem, the issue. Someone can help me? Thank U! |

Hi,
your simulation seems to be fully converged... how does it look like in Paraview? Martin |

Quote:
I don't understand this issue. absolutely :( |

If you decrease the tolerances for the linear equation solver in system/fvSolution even further to let's say "tolerance 1e-12;", then the initial residual is higher then desired and more iterations will be done...
But it shouldn't be necessary... your simulation results should be fine enough after a few hundred iterations. You can add "convergence 1e-5;" to the SIMPLE dictionary in the fvSolution. simpleFoam will stop as soon as convergence criteria is reached: Code:
`SIMPLE` |

Quote:
so the problem is in the solid model? |

If simpleFoam makes 0 iterations for solving the linear equations system in the very first time steps, too, than there is a problem in your case. On the other hand if simpleFoam do make more than 0 iterations in the first time steps, everything is fine: simpleFoam found the correct solution and further iterations are not necessary.
You can send me your case, if you like, so I can have a look at it... my eMail comes via boardmail to prevent spamming... Martin |

Quote:
I want to give him REP+ :) |

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