Print Email Facebook Twitter Computational study of flow incidence effects on the aeroacoustics of low blade-tip Mach number propellers Title Computational study of flow incidence effects on the aeroacoustics of low blade-tip Mach number propellers Author Romani, G. (TU Delft Wind Energy) Grande, E. (TU Delft Wind Energy) Avallone, F. (TU Delft Wind Energy) Ragni, D. (TU Delft Wind Energy) Casalino, D. (TU Delft Wind Energy) Date 2022 Abstract This paper presents a computational study of flow incidence effects on the aeroacoustics of a propeller operating at low blade-tip Mach numbers. The numerical flow solution is obtained by using the Lattice-Boltzmann/Very Large Eddy Simulation method, while far-field noise is computed through the Ffowcs-Williams & Hawkings' acoustic analogy applied on the propeller surface. The presence of an angular inflow leads to: (i) the radiation of tonal loading noise along the propeller axis; (ii) the increment/reduction of the sound pressure level in the region from/to which the propeller is tilted away/towards. However, contrarily to propellers operating at high blade-tip Mach numbers, the noise directivity change is found to be governed only by the rise of periodic unsteady loadings, with the modulation of the strength of the noise sources on the blade, associated to the periodic variation of the observer-source relative Mach number (in the blade reference frame), being negligible. Finally, thickness noise and turbulent boundary-layer trailing-edge noise did not show a significant directivity variation due to the propeller yaw angle change. Subject AeroacousticsAerodynamicsDroneLattice-Boltzmann methodPropellerYaw angle To reference this document use: http://resolver.tudelft.nl/uuid:b090d8e9-b621-46f6-a986-c6790936f01b DOI https://doi.org/10.1016/j.ast.2021.107275 ISSN 1270-9638 Source Aerospace Science and Technology, 120 Part of collection Institutional Repository Document type journal article Rights © 2022 G. Romani, E. Grande, F. Avallone, D. Ragni, D. Casalino Files PDF 1_s2.0_S1270963821007859_main.pdf 4.1 MB Close viewer /islandora/object/uuid:b090d8e9-b621-46f6-a986-c6790936f01b/datastream/OBJ/view