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Old   August 8, 2016, 08:04
Default Courant criteria
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Samraj Manickam Palvannan
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Hello all,
I have been trying a flow simulation. I get missing elements error which i suppose, is beacuse of Courant criterion. I calculated Courant number from division of time step to grid size. I get unrealistic cfl number from that. Could someone please help me with that? thank you very much.
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Old   September 7, 2016, 06:38
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Quote:
Originally Posted by samraj View Post
Hello all,
I have been trying a flow simulation. I get missing elements error which i suppose, is beacuse of Courant criterion. I calculated Courant number from division of time step to grid size. I get unrealistic cfl number from that. Could someone please help me with that? thank you very much.
Hi,

Which is the velocity of the node in the point that you get unrealistic cfl number? And you time step?

Regards.
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Old   October 7, 2016, 11:32
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Courant number is velocity in cell times time step divided by the cell size.

You are missing the velocity component in your calculation.
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Old   November 3, 2016, 03:14
Default CFL number
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Quote:
Originally Posted by thunde47 View Post
Courant number is velocity in cell times time step divided by the cell size.

You are missing the velocity component in your calculation.
Hi sorry I am new to CFD, i do not understand the velocity in cell ? Do I define this or I get it from the mesh information ??

Thanks!
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