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-   -   why did Time step is too small in stiffbs? (http://www.cfd-online.com/Forums/fluent/49995-why-did-time-step-too-small-stiffbs.html)

satum December 7, 2008 19:46

why did Time step is too small in stiffbs?
 
Hi, everyone. The following message appears when I activate the heat mass coupling in DPM panel. "Time step too small in stiffbs:

Time step too small in stiffbs: dt = 3.819282e-21, t = 4.316239e-04 0 y = 2.000002e-11 dy/dt = -1.075370e+03 1 y = 2.312000e+02 dy/dt = 0.000000e+00

Time step too small in stiffbs: dt = 3.589703e-21, t = 4.311432e-04 0 y = 2.000000e-11 dy/dt = -1.076570e+03 1 y = 2.312000e+02 dy/dt = 0.000000e+00

Time step too small in stiffbs: dt = 3.513279e-21, t = 4.311310e-04 0 y = 2.000002e-11 dy/dt = -1.076599e+03 1 y = 2.312000e+02 dy/dt = 0.000000e+00

Can you explain it?Thank you very much!


hityangsir December 10, 2012 09:15

Hey, satum. I met the same problem. BTW, have you found the reason? Thank you


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