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mscheng May 9, 2013 04:16

initial residual and final residual
what is the definition of the initial residual and final residual, which can be used to decide convergence ?

Anne Lincke May 15, 2013 05:20

The initial residual is evaluated based on the current values of the field before solving an equation for a particular field . The final residual is evaluated after the solution of the equation is performed.
The intial residual is more important to decide whether a computation converges, or not.

timo_IHS May 15, 2013 08:23

Hi Anne,

can you give some rule of thumbs for values, which should be achieved for the initial/final residual and how many iterations should be used for pEqn per cycle e.g. for a transient simulation with a standard PCG solver.

Best Timo

Anne Lincke May 15, 2013 08:29

Initial residual: e^-4 or e^-5 is a good result. Final residual has to be smaller (e^-8).
I cannot answer your 2nd question.

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