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Hi,

I'm trying to switch from sigma transformation to z-level transformation since the latter one may be beneficial for modeling of stratification with k-epsilon model. However, after several time steps, I got the error message:

@STREAMLINE::SCARACT:THE NUMBER OF TRACEBACK INTERFACE CROSSINGS IGEN>99

what does it mean? Is it possible to fix this problem?
Thanks for help.

Best regards.

Hello,

It means that when computing the characteristics (i.e. trajectories in some sense) more than 99 sub-domain boundaries are crossed. It always mean that you have a very large Courant number somewhere, so that the case is probably going to crash.

Regards,

JMH

Hi,

Thank you very much indeed for your quick reply.
Yes I did use the characterestic scheme with rather large time step (60s) for k-epsilon. So I will use a relatively small time step instead.

Best regards.

Hi,

Did you find a solution for this error?
Did you reduce your time step?

I have the same error.

Florian

Hi Florian,

Have you found a solution to your problem with number of characteristic interssect >99? I am getting it from time to time too. I have tried small time steps and it did not work. The only solution that works for me is to run it for short period of time and then use Previous Result file to continue computation. So basically do it in steps. But it is little bit messy as you never know when it is going to crash, so I wonder if you found a solution in mean time. Thanks in advance.

Kind Regards!

Violeta