[mr07th]

Hello everyone!
I am trying to simulate work of de Laval nozzle but I faced with a problem of reversed flow (which generates excess of the temperature and viscosity) in outlet. I have tried to solve this problem by means transfer of outlet from the nozzle but reversed flow appeared 200-300 iterations later. I am trying to solve with Inviscid and SST but this didn't help me.
Fluent's check mesh showed that mesh is good (max aspect ratio around 30, ortho skew 0.24, ortho qualiti 0.76).
So I screwed up bc and I can't understand what is wrong
I attached pictures with my settings.
If I set up operational pressure and gauge pressure (pressure outlet) as 0, I haven't problems with solving (reversed flow appears on inlet and after 300-400 iterations disappears) but this case for vacuum and I need solving for atmosphere. Anyone have any idea what is wrong ?