Rob
Ansys Employee

If it's fixed density use a velocity inlet, patch the jet in (carefully) and it may work. However, I suspect 75 bar will choke so you may need to rethink the inlet condition. 

Time steps should be set such that the flow crosses a cell in a few time steps. Otherwise most of the default solver settings will more-or-less be OK. Have a look in the tutorials, examples and Learning (top left here) for more tips.

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