When nozzles operate in overexpanded regime, as during engine startup and shutdown of space launchers, flow separations in the divergent section may occur and cause large lateral forces. More in general, flow separation is characterized by an oblique shock, necessary to permit the supersonic flow to deviate and to adapt to the ambient conditions. The separation shock always reflects on the nozzle axis by a Mach reflection, whose features depend on the upstream flow conditions, usually not uniform. In this paper the details of the shock structure and flowfield obtained in an overexpanded parabolic nozzle are analyzed using a novel shock-fitting technique.
Shock-Fitted Calculation of Steady Mach Reflections in Overexpanded Nozzles Using Structured Grids
Bonfiglioli, A.
2025-01-01
Abstract
When nozzles operate in overexpanded regime, as during engine startup and shutdown of space launchers, flow separations in the divergent section may occur and cause large lateral forces. More in general, flow separation is characterized by an oblique shock, necessary to permit the supersonic flow to deviate and to adapt to the ambient conditions. The separation shock always reflects on the nozzle axis by a Mach reflection, whose features depend on the upstream flow conditions, usually not uniform. In this paper the details of the shock structure and flowfield obtained in an overexpanded parabolic nozzle are analyzed using a novel shock-fitting technique.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
