S-shape Intake Diffuser : Boundary Condition
 

https://www.cfd-online.com/Forums/at...1&d=1602436223

How to define BC for s-shaped duct intake at outlet ???

https://www.cfd-online.com/Forums/at...1&d=1602437017

CFD simulation for intake [s-shaped] which is connected to gas-turbine [in real condition] . It operates at different altitudes [Po & To varring with height].

[/B]but it is not able to define the proper boundary condition at the outlet of the intake.[/B] ................. tried with Pressure outlet (70120 Pa) condition is not appropriate because it does not match the practical condition ........ is their proper way of defining it [at the outlet side], which matches the practical condition at outlet ?

Engine Details : m = 2.5 Kg/s [at ideal condition] {this much detail I know about gas turbine} at rpm = 4200


BC
pressure far field : Ma = 0.5 , Po = 70120 Pa , To = 268.5 K

Outlet BC ???????? [which is at AIP (Aerodynamic Interface Plane) as show in fig. ]

Hi Rishabh:

At the AIP, the flow is subsonic, so the bc is going to be oinfluenced by both engine (downstream) and upstream (s-duct). As a first shot, you can impose a mass flow boundary condition at exit - thisis equivalent to prescribing an average exit static pressure at the AIP.

HTH,

Sam.