ANALYSIS AND LOW ORDER MODELING OF THE ACOUSTIC DAMPING FOR HIGH-FREQUENCY COMBUSTION INSTABILITIES PREDICTION IN LIQUID ROCKET ENGINES

Alexandre Fougnie (1, 2) , Thomas Schmitt (2) , Sebastien Ducruix (2)

1 CNES - Centre National d'Etudes Spatiales - Direction Des Lanceurs.
2 EM2C - Laboratoire d'Énergétique Moléculaire et Macroscopique, Combustion

The phenomena liable for acoustic damping in thermo-acoustic instabilities in liquid rocket engines are investigated. Modelings to account for the nozzle impedance, in compact hypothesis, and for the visco-thermal losses at walls are derived according to the Galerkin framework, where pressure variations are decomposed over the acoustic eigenmodes. Models are implemented in a low order tool and compared successfully to analytic and numerical predictions. The turbulent/acoustic interaction, responsible for acoustic absorption at the jets, is reviewed, and an in-progress strategy is presented.

Mots clés: liquid rocket propulsion; thermo-acoustic instabilities; high-frequency instabilities; low order modeling; acoustic damping

Domaines: Sciences de l'ingénieur [physics]; Physique [physics]

Alexandre Fougnie, Thomas Schmitt, Sebastien Ducruix. ANALYSIS AND LOW ORDER MODELING OF THE ACOUSTIC DAMPING FOR HIGH-FREQUENCY COMBUSTION INSTABILITIES PREDICTION IN LIQUID ROCKET ENGINES. Space Propulsion 2022, May 2022, Estoril, Portugal. ⟨hal-03676560⟩