[Victor3]

Hi


I'm trying to learn OpenFOAM again after being away for a while. I've modified the icoFoam/elbow example with my own mesh. But It stops after a short while. The geometry is just a simple rectangle for testing.



control dict:

application     icoFoam;

startFrom       latestTime;

startTime       0;

stopAt          endTime;

endTime         6;

deltaT          0.005;

writeControl    timeStep;

writeInterval   20;

purgeWrite      0;

writeFormat     ascii;

writePrecision  6;

writeCompression off;

timeFormat      general;

timePrecision   6;

runTimeModifiable true;

0/U:

dimensions      [0 1 -1 0 0 0 0];

internalField   uniform (0 0 0);

boundaryField
{
    wall
    {
        type            noSlip;
    }

    inlet
    {
        type            fixedValue;
        value           uniform (0.01 0 0);
    }

    outlet
    {
        type            zeroGradient;
    }
}

Showing the end:

Courant Number mean: 0.79581 max: 63.1
smoothSolver:  Solving for Ux, Initial residual = 0.685782, Final residual = 9.41785e-06, No Iterations 66
smoothSolver:  Solving for Uy, Initial residual = 0.716174, Final residual = 8.69162e-06, No Iterations 63
smoothSolver:  Solving for Uz, Initial residual = 0.693323, Final residual = 8.51979e-06, No Iterations 59
DICPCG:  Solving for p, Initial residual = 0.713553, Final residual = 0.0356645, No Iterations 156
DICPCG:  Solving for p, Initial residual = 0.338417, Final residual = 0.0123583, No Iterations 3
DICPCG:  Solving for p, Initial residual = 0.033877, Final residual = 0.00167932, No Iterations 170
time step continuity errors : sum local = 0.00694275, global = 0.000103744, cumulative = -9.99947e-05
DICPCG:  Solving for p, Initial residual = 0.129921, Final residual = 0.00645082, No Iterations 151
DICPCG:  Solving for p, Initial residual = 0.25175, Final residual = 0.00949852, No Iterations 3
DICPCG:  Solving for p, Initial residual = 0.0337265, Final residual = 9.34626e-07, No Iterations 211
time step continuity errors : sum local = 3.23715e-06, global = 1.79642e-08, cumulative = -9.99768e-05
ExecutionTime = 24.94 s  ClockTime = 26 s

Time = 0.315

Courant Number mean: 1.13275 max: 119.556
smoothSolver:  Solving for Ux, Initial residual = 0.684699, Final residual = 9.86724e-06, No Iterations 104
smoothSolver:  Solving for Uy, Initial residual = 0.703938, Final residual = 9.742e-06, No Iterations 107
smoothSolver:  Solving for Uz, Initial residual = 0.690446, Final residual = 9.77228e-06, No Iterations 131
DICPCG:  Solving for p, Initial residual = 0.674098, Final residual = 0.0325922, No Iterations 151
DICPCG:  Solving for p, Initial residual = 0.357341, Final residual = 0.0124241, No Iterations 3
DICPCG:  Solving for p, Initial residual = 0.0348905, Final residual = 0.00174187, No Iterations 170
time step continuity errors : sum local = 0.00968451, global = 2.81742e-05, cumulative = -7.18026e-05
DICPCG:  Solving for p, Initial residual = 0.12856, Final residual = 0.00636255, No Iterations 147
DICPCG:  Solving for p, Initial residual = 0.266371, Final residual = 0.00985169, No Iterations 3
DICPCG:  Solving for p, Initial residual = 0.0348542, Final residual = 9.78138e-07, No Iterations 211
time step continuity errors : sum local = 4.60704e-06, global = 1.03763e-08, cumulative = -7.17922e-05
ExecutionTime = 25.42 s  ClockTime = 26 s

Time = 0.32

Courant Number mean: 1.16594 max: 69.504

[Svetlana]

I would suggest to upload the entire case so that others can see your geometry and mesh.

[peterhess]

deltaT seams to be very high!

Either reduce deltaT to about 0.00005.

Or

add those two lines to controlDict:

maxCo 1;

adjustTimeStep yes;

Or (better):

do both at the same time!

Like that the solver will start with a low Co. and modefi deltaT as it need to keep Co under 1!

What checkMesh tells? Is your mesh ok?

Regards

Peter