[Zoli]

Hi people!

How can be difference in the exit mach numer between 2 nozzles with the same throat and exit areas, and with the same length? One nozzle is conical, and the second is designed using MoC....The Isoentropic realtions aren't correct in this case?

I simulated the both nozzles in Fluent 6.3.
Pressure inlet: Total Pressure: 101325 Pa
Initial Pressure: 100000
Total Temperature: 293.15 K

Pressure outlet: Gauge pressure: 5000Pa
Backflow total Temperature: 122K

The model is axisymmetric, solver density based.

The exit Mach numer should be 2.61 - from the isentropic relations
The exit Mach number of the Conical nozzle is 3.92Mach
MoC nozzle is 5.97Mach...