[Nek5000-users] turboJet problem...

[nek5000-users at lists.mcs.anl.gov]

Hello,
I am rechecking the example turboJet. I have several questions:

1. Concerning DNS/LES: in the example, the viscosity is -10935. This is 
certainly a very small viscosity which corresponds to LES. The parameter 
param(101)=1 and param(103)=0.05. If I wish to simulate DNS what would 
be the values of param(101),param(103) and viscosity (param(1)) in this 
particular example?

2. As the simulation progresses, it seems that the current CFL suddenly 
grows and eventually the simulation blows up. I divided up the time step 
up to 0.0005 and it still crashes. I am using TORDER=2 which has a 
larger region of stability, without a significant success.
I looked at the mailing list archive and found in 2010 a posting which 
refers to variable time stepping:
http://lists.mcs.anl.gov/pipermail/nek5000-users/2010-July/000778.html
Is it relevant to my case, and if it so, how can adapt it in turboJet 
example?


Many thanks,
Barak Galanti