Fluid/Pipe model

[LPSavoie]

It is well known the pipe model does not handle choked flow conditions at all.
However valves and orifices are meant to handle choked flow conditions, and therefore it is good practice to add an orifice in series with a pipe when choked flows are present... but the problem is that even the orifices badly handle choked flow conditions.
Could we start some investigations on choked flow conditions and get some improvement on the pipe or orifice models?