PhD - Inverse modal identification of free-field radiated noise from unducted rotor-stator stages: from laboratory arrays to Open Fan flight tests

This postdoctoral position is part of the European project TAKE-OFF (Clean Aviation programme), which is preparing the full-scale flight demonstration of Safran Aircraft Engines’ RISE Open Fan engine on the Airbus A380 flying testbed, with the aim of reducing fuel consumption by 30 % and entering service around 2035. Without a nacelle, the engine noise sources radiate directly into free field. LMFA (École Centrale de Lyon), in collaboration with LVA (INSA Lyon), is in charge of analysing the near-field pressure data acquired in flight by microphones installed on the fuselage, in order to reconstruct the engine noise sources.

To extend the modal analysis methods developed at LMFA for ducted engines [1] to unducted fans. For the first time, modal analysis will be applied to microphones located in an unconfined medium and to modes radiating under free-field conditions, and design criteria specific to this configuration will be established (spatial sampling, resolution, array-to-rotor distance relative to the array size).

PhD in acoustics, aeroacoustics or signal processing; skills in array methods, inverse problems and/or modal analysis; scientific programming (Python/Matlab).

[1] Pereira, A. & Jacob, M.C., 2022, Modal analysis of in-duct fan broadband noise via an iterative Bayesian inverse approach, J. Sound Vib., doi:10.1016/j.jsv.2021.116633.

[2] Roger, M. & Kucukcoskun, K., 2019, Near-and-far field modeling of advanced tail-rotor noise using source-mode expansions, J. Sound Vib., 453, 328-354.

LMFA contacts: Antonio Pereira, Marc Jacob

LVA contact: Quentin Leclère (LVA, INSA Lyon)

Funding: European project TAKE-OFF (Technology and Knowledge for European Open Fan Flight)