CFD Online Discussion Forums - What is the difference between "includefunc residuals" and the residuals in log-file?

Hi,

I'm trying to run an inviscid, incompressible flow (Euler equations) around a wing with simpleFoam with nu set to zero. I'm trying to judge convergence and noticed that the final residuals in the log-file (by running simpleFoam > log) are in the order of e-09, whereas the residuals in the .dat file generated with "includefunc residuals" are in the order of e-02. What is the difference between the two? Why are they not the same?

Here's the last log entry:

Code:

Time = 3000



DILUPBiCG:  Solving for Ux, Initial residual = 0.00244323, Final residual = 6.17655e-10, No Iterations 8

DILUPBiCG:  Solving for Uy, Initial residual = 0.0121557, Final residual = 7.31898e-09, No Iterations 7

DILUPBiCG:  Solving for Uz, Initial residual = 0.00547038, Final residual = 2.36399e-09, No Iterations 8

DICPCG:  Solving for p, Initial residual = 0.0347422, Final residual = 8.60062e-07, No Iterations 75

time step continuity errors : sum local = 2.02144e-08, global = -2.11615e-09, cumulative = -2.57245e-07

ExecutionTime = 235.96 s  ClockTime = 236 s



End

Here's the last residuals.dat entry:

Code:

# Time            p                 Ux                Uy                Uz 



3000              3.474220e-02    2.443230e-03    1.215570e-02    5.470380e-03

Thanks!

Bruno