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Effect of geometrical features on the noise of propellers through time-domain and frequency-domain broadband noise predictions / Akila Halimi 

Public ISBD Titre : Effect of geometrical features on the noise of propellers through time-domain and frequency-domain broadband noise predictions Type de document : texte imprimé Auteurs : Akila Halimi, Auteur ; Larbi, Salah, Directeur de thèse ; G. Marinus, Directeur de thèse Editeur : [S.l.] : [s.n.] Année de publication : 2020 Importance : 164 f., 1 Fichier PDF (8.2 Mo) Présentation : ill. Format : 30 cm. Note générale : Mode d'accès : accès au texte intégral par intranet. Thèse de Doctorat : Génie Mécanique : Alger, École Nationale Polytechnique : 2020 Bibliogr. f. 157 - 164 Langues : Anglais (eng) Mots-clés : Aeroacoustics  ;  Broadband  noise  ;  Propeller  ;  Serrations  ;  Analytical  model  ;  LatticeBolzmann  method Index. décimale : D001120 Résumé : This study aims at investigating into the capability of reducing the broadband noise of a propeller, by means of sawtooth trailing edge and leading edge serrations. New analytical models for predicting noise from airfoils with serrated edges are implemented and applied to propellers using a blade strip approach. These models are assessed by comparison with spectra obtained from time-domain Lattice Boltzmann Method simulations.Obtained results showed that the analytical models are able to predict the noise from either straight or serrated propellers with a good accuracy. A parametric study was conducted to predict the noise emitted by propellers featuring sawtooth trailing edge or leading edge serrations with different parameters. The results of the serratedtrailing edge show that the use of serrations reduces the noise emitted by the propellers at low to mid frequencies but induces a noise increase at high frequencies. The sharpest serrations were found to achieve the better performance in terms of reducingnoise. For the serrated leading edge, the results show that the serrations are effective in reducing the noise emitted by the propellers at high frequencies. The noise reduction increases with the increased serration amplitude, while the variation of serration wavelength shows no significant effect on the noise reduction Effect of geometrical features on the noise of propellers through time-domain and frequency-domain broadband noise predictions [texte imprimé] / Akila Halimi, Auteur ; Larbi, Salah, Directeur de thèse ; G. Marinus, Directeur de thèse . - [S.l.] : [s.n.], 2020 . - 164 f., 1 Fichier PDF (8.2 Mo) : ill. ; 30 cm. Mode d'accès : accès au texte intégral par intranet. Thèse de Doctorat : Génie Mécanique : Alger, École Nationale Polytechnique : 2020 Bibliogr. f. 157 - 164 Langues : Anglais (eng) Mots-clés : Aeroacoustics  ;  Broadband  noise  ;  Propeller  ;  Serrations  ;  Analytical  model  ;  LatticeBolzmann  method Index. décimale : D001120 Résumé : This study aims at investigating into the capability of reducing the broadband noise of a propeller, by means of sawtooth trailing edge and leading edge serrations. New analytical models for predicting noise from airfoils with serrated edges are implemented and applied to propellers using a blade strip approach. These models are assessed by comparison with spectra obtained from time-domain Lattice Boltzmann Method simulations.Obtained results showed that the analytical models are able to predict the noise from either straight or serrated propellers with a good accuracy. A parametric study was conducted to predict the noise emitted by propellers featuring sawtooth trailing edge or leading edge serrations with different parameters. The results of the serratedtrailing edge show that the use of serrations reduces the noise emitted by the propellers at low to mid frequencies but induces a noise increase at high frequencies. The sharpest serrations were found to achieve the better performance in terms of reducingnoise. For the serrated leading edge, the results show that the serrations are effective in reducing the noise emitted by the propellers at high frequencies. The noise reduction increases with the increased serration amplitude, while the variation of serration wavelength shows no significant effect on the noise reduction

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Code-barres	Cote	Support	Localisation	Section	Disponibilité	Spécialité	Etat_Exemplaire
T000297	D001120	Papier	Bibliothèque centrale	Thèse de Doctorat	Disponible	Genie_mecanique	Consultation sur place

Documents numériques

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