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field versus equation under relaxation factors

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Old   July 15, 2012, 18:20
Default field versus equation under relaxation factors
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Mihai Pruna
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what do the equation relaxation factors do. I noticed if I set any equation under relaxation factor to under 0.9 in rhoSimplecFoam I get a floating point error during the first time step.
For instance, the values below do work but anything lower in equation under-relaxation factors will cause a crash when calculating h.





p 0.30000;

rho 0.3000;
U 0.3;




U 0.90000;

h 0.90000;

k 0.90000;

omega 0.90000;


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Old   February 1, 2016, 06:08
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Under-relaxation works by limiting the amount which a variable changes from one iteration to the next, either by modifying the solution matrix and source prior to solving for a field or by modifying the field directly.
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