Hi,

Essentially the iterative solver does not converge. Probably in the passive scalar solve. I would guess that diffusivity of the passive scalar is significantly lower than viscosity. If this is the case, try to set it to be the same as viscosity (Schmidt or Prandtl number = 1). If this works, and solution progresses, you can try to play with the time step size while decreasing diffusivity to where you want it to be. This way you might get the acceptable time step size for your problem.

Best regards,
Stanisław Gepner, Ph.D.

Faculty of Power and Aeronautical Engineering
Nowowiejska 21/25 Str.
00-665 Warsaw, Poland
phone +48 (22) 234 51 70

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Dear all,

When I run a 2.5D simulation with a coordinate transformation and an extra passive scalar transport, I get the following error:

      

      CG iterations made = 5001 using tolerance of 1e-09 (error = -nan, rhs_mag = 1)

      Fatal   : Level 0 assertion violation

      Exceeded maximum number of iterations

However, if I repeat the simulation without the passive scalar transport, it proceeds correctly.

Has anyone else encountered the same problem? If so, would you be able to assist me in resolving it?

Thank you in advance for youe help,

Antonio.

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