[hsieh]

When restarting a interDyMFoam 6DoF case, ,maximum gamma field jumped to something like 1.005. Then, as simulation progress, gamma field starts to decreases back to 1 (took several time steps). Can this be fixed?

[henry]

Are you running with "pcorr"? This is useful particularly for restarting as in ensures the fluxes obey continuity.

H

[hsieh]

Hi, Henry,

Can you explain what you meant by using "pcorr"?

I ran the tutorial case: sloshingTank3D6Dof. Stopped at around time=0.2, then, restart the case, max(gamma) jumpped to 1.00018.

Pei
------------------------------
Courant Number mean: 0.0180309 max: 0.134522
deltaT = 0.01
Time = 0.24

solidBodyMotionFunctions::SKA::transformation(): Time = 0.24 transformation: ((0.238371 0.566023 0.191165) (0.999524 (0.0251673 0.0142001 0.0107583)))
Execution time for mesh.update() = 0.07 s
MULES: Solving for gamma
Liquid phase volume fraction = 0.336944 Min(gamma) = -9.7157e-32 Max(gamma) = 1
MULES: Solving for gamma
Liquid phase volume fraction = 0.336944 Min(gamma) = -1.29559e-31 Max(gamma) = 1
MULES: Solving for gamma
Liquid phase volume fraction = 0.336945 Min(gamma) = -2.93586e-29 Max(gamma) = 1
GAMG: Solving for pd, Initial residual = 0.0350727, Final residual = 0.00011057, No Iterations 2
time step continuity errors : sum local = 8.36176e-07, global = 4.93122e-16, cumulative = 8.41075e-16
^C
phsieh@huwei:~/OpenFOAM/phsieh-1.5/run/sloshingTank3D6DoF> interDyMFoam
/*---------------------------------------------------------------------------*\
| ========= | |
| \ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \ / O peration | Version: 1.5 |
| \ / A nd | Web: http://www.OpenFOAM.org |
| \/ M anipulation | |
\*---------------------------------------------------------------------------*/
Exec : interDyMFoam
Date : Jan 24 2009
Time : 20:06:46
Host : huwei
PID : 7870
Case : /home/phsieh/OpenFOAM/phsieh-1.5/run/sloshingTank3D6DoF
nProcs : 1

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time

Create mesh for time = 0.2

Selecting dynamicFvMesh solidBodyMotionFvMesh
Selecting solid-body motion function SKA

Reading environmentalProperties
Reading field pd

Reading field gamma

Reading field U

Reading/calculating face flux field phi

Reading transportProperties

Selecting incompressible transport model Newtonian
Selecting incompressible transport model Newtonian
Selecting RAS turbulence model laminar
time step continuity errors : sum local = 4.44746e-08, global = 2.11252e-21, cumulative = 2.11252e-21
GAMGPCG: Solving for pcorr, Initial residual = 1, Final residual = 2.196e-06, No Iterations 4
time step continuity errors : sum local = 9.80761e-14, global = 1.18062e-20, cumulative = 1.39187e-20
Courant Number mean: 0.018024 max: 0.133732

Starting time loop

Courant Number mean: 0.0450601 max: 0.334331
deltaT = 0.025
--> FOAM Warning :
From function probes::read()
in file probes/probes.C at line 72
Did not find location (0 -9.95 19.77) in any cell. Skipping location.
Time = 0.225

solidBodyMotionFunctions::SKA::transformation(): Time = 0.225 transformation: ((0.223473 0.530646 0.179218) (0.999582 (0.0235863 0.0133285 0.0100652)))
Execution time for mesh.update() = 0.07 s
MULES: Solving for gamma
Liquid phase volume fraction = 0.336941 Min(gamma) = -2.59392e-33 Max(gamma) = 1.00006
MULES: Solving for gamma
Liquid phase volume fraction = 0.336943 Min(gamma) = -3.55382e-35 Max(gamma) = 1.00012
MULES: Solving for gamma
Liquid phase volume fraction = 0.336945 Min(gamma) = -3.72389e-30 Max(gamma) = 1.00018
GAMG: Solving for pd, Initial residual = 0.121794, Final residual = 0.00038103, No Iterations 2
time step continuity errors : sum local = 1.60598e-05, global = 1.84704e-08, cumulative = 1.84704e-08
GAMGPCG: Solving for pd, Initial residual = 0.000912832, Final residual = 2.96859e-10, No Iterations 6
time step continuity errors : sum local = 1.84832e-08, global = 1.84704e-08, cumulative = 3.69408e-08
ExecutionTime = 1.49 s ClockTime = 2 s

Courant Number mean: 0.0450506 max: 0.335793
deltaT = 0.025
Time = 0.25

solidBodyMotionFunctions::SKA::transformation(): Time = 0.25 transformation: ((0.248303 0.589607 0.199131) (0.999484 (0.0262219 0.01478 0.0112219)))
Execution time for mesh.update() = 0.07 s
MULES: Solving for gamma
Liquid phase volume fraction = 0.336948 Min(gamma) = -9.31185e-30 Max(gamma) = 1.00017
MULES: Solving for gamma
Liquid phase volume fraction = 0.336951 Min(gamma) = -5.46996e-30 Max(gamma) = 1.00017
MULES: Solving for gamma
Liquid phase volume fraction = 0.336953 Min(gamma) = -3.03636e-29 Max(gamma) = 1.00017
GAMG: Solving for pd, Initial residual = 0.0875576, Final residual = 0.000255096, No Iterations 2
time step continuity errors : sum local = 1.12223e-05, global = -6.35855e-16, cumulative = 3.69408e-08
GAMGPCG: Solving for pd, Initial residual = 0.000569134, Final residual = 2.28459e-10, No Iterations 6
time step continuity errors : sum local = 1.05782e-11, global = -6.35799e-16, cumulative = 3.69408e-08
ExecutionTime = 3.04 s ClockTime = 3 s

Courant Number mean: 0.0450544 max: 0.337487
deltaT = 0.025
Time = 0.275

solidBodyMotionFunctions::SKA::transformation(): Time = 0.275 transformation: ((0.273134 0.648568 0.219044) (0.999375 (0.0288603 0.0162254 0.012386)))
Execution time for mesh.update() = 0.07 s
MULES: Solving for gamma
Liquid phase volume fraction = 0.336956 Min(gamma) = -3.10686e-31 Max(gamma) = 1.00017
MULES: Solving for gamma
Liquid phase volume fraction = 0.336959 Min(gamma) = -2.57869e-31 Max(gamma) = 1.00016
MULES: Solving for gamma
Liquid phase volume fraction = 0.336962 Min(gamma) = -1.94614e-30 Max(gamma) = 1.00016

[henry]

You will see that pcorr is solved at the beginning of the first time-step after restart; this is to ensure the phi obeys continuity. Try tightening the tolerance on pcorr.

Also try writing the results binary and see if that reduces the restart error.

H

[hsieh]

Hi, Henry,

writing results in binary seemed to resolve this issue.

Thanks!

Pei