The sea-level start-up of rocket engines is characterized by the nozzle overexpansion and an internal flow separation with a strong unsteady shock wave boundary layer interaction (SWBLI). This produces side-loads, which reduce the safe life of the engine. In this work, a 3D planar overexpanded nozzle has been simulated by means of the Detached Eddy Simulation technique. The pressure signals have been analyzed by the wavelet decomposition. The results indicate that the shock unsteadiness has been captured and that the characteristics frequencies are close to the ones available from literature. The shock excursion seems to be too high and requires further investigations.
Delayed detached eddy simulation of separated flows in a planar nozzle / Martelli, E.; Ciottoli, P.; Bernardini, M.; Nasuti, F.; Valorani, M.. - ELETTRONICO. - (2017). (Intervento presentato al convegno 7 TH EUROPEAN CONFERENCE FOR AERONAUTICS AND AEROSPACE SCIENCES (EUCASS) tenutosi a Milano nel 3-6 luglio 2017) [10.13009/EUCASS2017-582].
Delayed detached eddy simulation of separated flows in a planar nozzle
P. Ciottoli;M. Bernardini;F. Nasuti;M. Valorani
2017
Abstract
The sea-level start-up of rocket engines is characterized by the nozzle overexpansion and an internal flow separation with a strong unsteady shock wave boundary layer interaction (SWBLI). This produces side-loads, which reduce the safe life of the engine. In this work, a 3D planar overexpanded nozzle has been simulated by means of the Detached Eddy Simulation technique. The pressure signals have been analyzed by the wavelet decomposition. The results indicate that the shock unsteadiness has been captured and that the characteristics frequencies are close to the ones available from literature. The shock excursion seems to be too high and requires further investigations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
