The axisymmetric screech modes, which arise as part of a resonance cycle, are considered here for purely converging round twin-jets. Linear stability models, vortex-sheet and finite thickness, are employed to consider the underlying physics of the resonance involved. Strong agreement is found between both the models and experimental acoustic data, in particular forming a sharp bound to the cut-on screech frequency. When considering the symmetry of the screech modes, symmetric or antisymmetric, the experimental measurements indicated regions of antisymmetry that were not supported by the vortex-sheet model. Whereas the finite thickness model could support this across part of the nozzle pressure range and provided distinct predictions for the two symmetries.
Stavropoulos, M.N., Mancinelli, M., Jordan, P., Jaunet, V., Edgington-Mitchell, D.M., Nogueira, P.A.S. (2022). Analysis of axisymmetric screech tones in round twin-jets using linear stability theory. In 28th AIAA/CEAS Aeroacoustics conference [10.2514/6.2022-3071].
Analysis of axisymmetric screech tones in round twin-jets using linear stability theory
Mancinelli M.;Jordan P.;
2022-01-01
Abstract
The axisymmetric screech modes, which arise as part of a resonance cycle, are considered here for purely converging round twin-jets. Linear stability models, vortex-sheet and finite thickness, are employed to consider the underlying physics of the resonance involved. Strong agreement is found between both the models and experimental acoustic data, in particular forming a sharp bound to the cut-on screech frequency. When considering the symmetry of the screech modes, symmetric or antisymmetric, the experimental measurements indicated regions of antisymmetry that were not supported by the vortex-sheet model. Whereas the finite thickness model could support this across part of the nozzle pressure range and provided distinct predictions for the two symmetries.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.