Some Questions about GAMG

bastil · February 10, 2009, 18:03

Hi FOAMERS,

I am currently doing some numerical studies and I have some questions about the 1.5 GAMG:

1. Is it still possible to specify maximum iteration number as for amg before? Default seems to be 1000 which takes years....

2. I sometimes see a run switching from less than 20 to 1000 GAMG iterations from one iteration to the next (simpleFoam) WHat can this be caused by? Initial and final residuals look very similar.

Thanks BastiL

bastil · March 2, 2009, 03:59

A pity, nobody seems to know this? Do I have to edit the source for this? The first topic is still of interest for me.

Regards

vinz · March 2, 2009, 04:21

Hello Bastil,

For point 1, normaly specifying "maxIter N;" in your fvSOlution file works even with GAMG. At least, it works for me.
For point 2, I would say that your simulation is simply blowing up, which is shown by the large differences in behaviour you noticed.

Regards,

Vincent

February 10, 2009, 18:03	Hi FOAMERS, I am currently	#1
bastil Senior Member BastiL Join Date: Mar 2009 Posts: 530 Rep Power: 20	Hi FOAMERS, I am currently doing some numerical studies and I have some questions about the 1.5 GAMG: 1. Is it still possible to specify maximum iteration number as for amg before? Default seems to be 1000 which takes years.... 2. I sometimes see a run switching from less than 20 to 1000 GAMG iterations from one iteration to the next (simpleFoam) WHat can this be caused by? Initial and final residuals look very similar. Thanks BastiL

March 2, 2009, 03:59	A pity, nobody seems to know t	#2
bastil Senior Member BastiL Join Date: Mar 2009 Posts: 530 Rep Power: 20	A pity, nobody seems to know this? Do I have to edit the source for this? The first topic is still of interest for me. Regards

March 2, 2009, 04:21	Hello Bastil, For point 1,	#3
vinz Senior Member Vincent RIVOLA Join Date: Mar 2009 Location: France Posts: 283 Rep Power: 18	Hello Bastil, For point 1, normaly specifying "maxIter N;" in your fvSOlution file works even with GAMG. At least, it works for me. For point 2, I would say that your simulation is simply blowing up, which is shown by the large differences in behaviour you noticed. Regards, Vincent

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