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fppimenta / rheoTool

Toolbox to simulate GNF and viscoelastic fluid flows in OpenFOAM®
GNU General Public License v3.0
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CFL number control #30

Closed zhukansi closed 4 years ago

zhukansi commented 4 years ago

Hi: I have a question about CFL number.The case of Nerstblanck in ICEO has a very small CFL number and the result gets worse if I increase the number.Normally,we set the CFL to 2or1,but why it's so small in our case?Is there any theory about it?

fppimenta commented 4 years ago

In low Re flows, the Courant number is usually not very useful (I rarely look to it), because there are more restrictive conditions for stability. In EO, for example, the diffusive time-scale of ionic species is typically the most stringent condition.

zhukansi commented 4 years ago

In low Re flows, the Courant number is usually not very useful (I rarely look to it), because there are more restrictive conditions for stability. In EO, for example, the diffusive time-scale of ionic species is typically the most stringent condition.

I got it! Thanks.