The paper deals with the spacetime reinterpretation of the phenomenon of aeroacoustic convection within the framework of the Lorentzian differential geometry. Specifically, the effect of the background aerodynamic velocity field on the propagation of the acoustic disturbances is revisited in terms of spacetime curvature. The analysis explores the local properties of the curved aeroacoustic spacetime to correlate the background aerodynamics with the local value of the Riemann's scalar, and the latter with the convective effect. The metric associated to the aeroacoustic spacetime is compare with that induced by the inverse Taylor transformation, which is based on the O(M) approximation of the convective wave equation. Although limited by the low-speed assumption, the inverse Taylor transformation bends the Minkowskian (i.e., flat) acoustic spacetime taking into account the spatial variation of the background velocity potential. Numerical simulations are conducted to verify and visualise the spacetime properties
Iemma, U., Palma, G. (2019). SpaceTime-bending transformations in aeroacoustics. In Proceedings of the 26th International Congress on Sound and Vibration, ICSV 2019. ;P.O. Box 74068 : Canadian Acoustical Association.
SpaceTime-bending transformations in aeroacoustics
Iemma U.;Palma G.
2019-01-01
Abstract
The paper deals with the spacetime reinterpretation of the phenomenon of aeroacoustic convection within the framework of the Lorentzian differential geometry. Specifically, the effect of the background aerodynamic velocity field on the propagation of the acoustic disturbances is revisited in terms of spacetime curvature. The analysis explores the local properties of the curved aeroacoustic spacetime to correlate the background aerodynamics with the local value of the Riemann's scalar, and the latter with the convective effect. The metric associated to the aeroacoustic spacetime is compare with that induced by the inverse Taylor transformation, which is based on the O(M) approximation of the convective wave equation. Although limited by the low-speed assumption, the inverse Taylor transformation bends the Minkowskian (i.e., flat) acoustic spacetime taking into account the spatial variation of the background velocity potential. Numerical simulations are conducted to verify and visualise the spacetime propertiesI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
