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 ztdep September 14, 2005 08:19

1,what is the meaning of the "

1,what is the meaning of the "time step continuity errors "
2, why the openfoam solve the P equation for two times .

time step continuity errors
Mean and max Courant Numbers = 0.104862 1.499
BICCG: Solving for Ux, Initial residual = 0.126377, Final residual = 5.5659e-06, No Iterations 12
BICCG: Solving for Uy, Initial residual = 0.340201, Final residual = 6.705e-06, No Iterations 13
ICCG: Solving for p, Initial residual = 0.661742, Final residual = 8.73282e-07, No Iterations 67
time step continuity errors : sum local = 8.54754e-09, global = 1.00275e-18, cumulative = 9.91247e-19
ICCG: Solving for p, Initial residual = 0.527485, Final residual = 9.40264e-07, No Iterations 66
time step continuity errors : sum local = 1.06335e-08, global = -1.84043e-19, cumulative = 8.07204e-19
ExecutionTime = 0.11 s

 niklas September 14, 2005 08:25

2. because you have said so.

2. because you have said so.

 amelia September 14, 2005 15:28

I would also like to know abou

I would also like to know about the meaning of the continuity errors. Is it the same as the mass conservation error?

 wikstrom September 15, 2005 10:11

1) Have a look at continuity

1)
Have a look at continuityErrs.H (\$FOAM_SRC/cfdTools/incompressible/continuityErrs.H)

The implementation is rather instructive.

2)
Look in the case file: system/fvSolution, where you define the number of PISO corrections.

 liugx212 December 14, 2005 17:40

Dear All, I also encounter

Dear All,

I also encounter this question when I run icoFoam case with 92*92*32 mesh. my time step is 0.005. I am not sure how to solve this problem. Increase or decrease the PISO or others? Could you please give some advice?

Thanks a lot,
Guoxiang

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