Agradecimentos: This work was partially supported by the EU Project JERONIMO (call reference number: FP7-AAT-2012-RTD1; Grant agreement number: 314692), and by Airbus. The authors acknowledge the financial support received from Fundação de Amparo a Pesquisa do Estado de Sa~o Paulo, FAPESP, under...

Agradecimentos: This work was partially supported by the EU Project JERONIMO (call reference number: FP7-AAT-2012-RTD1; Grant agreement number: 314692), and by Airbus. The authors acknowledge the financial support received from Fundação de Amparo a Pesquisa do Estado de Sa~o Paulo, FAPESP, under Grant No. 2013/03413-4, and from the Science without Borders program (project number A073/ 2013).

Installed jet noise is studied by means of a simplified configuration comprising a flat plate in the vicinity of a round jet. The effects of Mach number, jet-plate radial distance, and trailing-edge sweep angle are explored. Acoustic measurements are performed using a traversable 18-microphone...

Installed jet noise is studied by means of a simplified configuration comprising a flat plate in the vicinity of a round jet. The effects of Mach number, jet-plate radial distance, and trailing-edge sweep angle are explored. Acoustic measurements are performed using a traversable 18-microphone azimuthal array, providing pressure data at 360 points on a cylindrical surface surrounding the jet-plate system. Key observations include a decrease, with increasing Mach number, of the relative level of the scattered field in comparison to the uninstalled jet; an exponential dependence of the scattered sound pressure level on the radial jet-plate separation; and considerable sideline noise reductions with increasing sweep angle, with which there is an overall reduction in acoustic efficiency. The measurements are compared with results obtained using a kinematic wavepacket source model, whose radiation is computed in two ways. A TGF for a semi-infinite flat plate is used to provide a low-order approximation of the scattering effect. Use of a more computationally intensive boundary element method provides additional precision. Good agreement between model predictions and experiment, encouraging from the perspective of low-cost prediction strategies, demonstrates that the models comprise the essential sound generation mechanisms

FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP

2013/03413-4

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