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Why does dtmax affect stability limits with fixed epsi?

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Old   December 16, 2009, 10:47
Default Why does dtmax affect stability limits with fixed epsi?
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gennady Markelov
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I use a fixed epsi and sometimes F3D applies a very small time step due to stability limits. I have found that a decrease of dtmax leads to increase of stability limits and time step. It sounds good because residuals are still kept below epsi and F3D runs faster. But this is like a magic.
Please could somebody give a hint why this happens?

Thank you.
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Old   December 26, 2009, 13:43
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michael barkhudarov
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Quote:
Originally Posted by gennady View Post
I use a fixed epsi and sometimes F3D applies a very small time step due to stability limits. I have found that a decrease of dtmax leads to increase of stability limits and time step. It sounds good because residuals are still kept below epsi and F3D runs faster. But this is like a magic.
Please could somebody give a hint why this happens?

Thank you.
Gennady,

Did my email to you with response to this question last week make sense?

Michael
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