Three-Dimensional Instability of Shock-Wave/Boundary-Layer Interaction for Rocket Engine Nozzle Applications
Résumé
A fully three-dimensional analysis is carried out on an over-expanded rocket engine
nozzle configuration in order to investigate the role of the internal shock-induced separation
on the mechanism of generation of side loads during start-up and shut-down transients. A
hybrid URANS/LES approach based on the delayed detached eddy simulations turbulence
model is used. Reasonable good agreement is obtained between numerical and experimental
results. The wall-pressure spectrum shows a narrow peak at f≈2000 Hz and a dynamic mode
decomposition reveals this to be associated to a mode whose characteristics resemble the
experimental azimuthal mode believed to be the cause of the generation of side loads.