Numerical simulations of overexpanded rocket nozzle flows show three kinds of flow separation structure: the free shock separation (FSS), the restricted shock separation (RSS), and an intermediate configuration which is a FSS with “inviscid separation” in the nozzle core. The paper presents a number of numerical simulations carried out with different nozzle geometries and chamber-to-ambient pressure ratios, with the goal to understand which are the geometries and the range of pressure ratio which lead to each different flow separation structure. The results show a good agreement with available experimental data and that RSS takes place only in case of strong radial gradients in the nozzle divergent section. Moreover, it is found that “inviscid separation” is much more likely to occur than RSS.
Numerical Analysis of Flow Separation Structures in Rocket Nozzles / Nasuti, Francesco; Onofri, Marcello; E., Martelli. - (2007), pp. 1-11. (Intervento presentato al convegno 43rd AIAA/ASME/SAE/ASEE Joint Propulsion Conference tenutosi a Cincinnati, OH, USA nel 8-11 luglio 2007).
Numerical Analysis of Flow Separation Structures in Rocket Nozzles
NASUTI, Francesco;ONOFRI, Marcello;
2007
Abstract
Numerical simulations of overexpanded rocket nozzle flows show three kinds of flow separation structure: the free shock separation (FSS), the restricted shock separation (RSS), and an intermediate configuration which is a FSS with “inviscid separation” in the nozzle core. The paper presents a number of numerical simulations carried out with different nozzle geometries and chamber-to-ambient pressure ratios, with the goal to understand which are the geometries and the range of pressure ratio which lead to each different flow separation structure. The results show a good agreement with available experimental data and that RSS takes place only in case of strong radial gradients in the nozzle divergent section. Moreover, it is found that “inviscid separation” is much more likely to occur than RSS.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.