Noise Generation of a Bionic Airfoil Based on Owl Wings

A bionic airfoil is used to investigate a preliminary understanding of the noise mechanism generated by the flow around the owl wing. The flow indicates a transitional separation bubble on the surface and the turbulent boundary layer reattaches at the downstream end of the bubble. This causes turbul...

Full description

Bibliographic Details
Main Author: Ge Changjiang
Format: Article
Language:English
Published: EDP Sciences 2017-01-01
Series:MATEC Web of Conferences
Online Access:https://doi.org/10.1051/matecconf/201711403003
_version_ 1818914978817638400
author Ge Changjiang
author_facet Ge Changjiang
author_sort Ge Changjiang
collection DOAJ
description A bionic airfoil is used to investigate a preliminary understanding of the noise mechanism generated by the flow around the owl wing. The flow indicates a transitional separation bubble on the surface and the turbulent boundary layer reattaches at the downstream end of the bubble. This causes turbulent boundary layer trailing-edge scattering noise corresponding to the broadband noise of owl wings at low Reynolds numbers. Furthermore, a large-scale vortex detaches from the bubble and then drifts downstream. Thus, a tone will be generated by the vortex shedding. However, the computations of the acoustic field for both cases, where the on-body data surface and the off-body data surface are used respectively, predominantly verify the broadband nature of the noise that well agrees with the noise scattering caused by the turbulent boundary layer passing by the sharp trailing edge. Furthermore, the significant decrease of the spectra around 2k Hz is consistent with that of silent owl wings. This fact suggests that the numerical simulations are capturing the basic physical mechanism responsible for the noise radiated by the natural owl wing. This might be able to provide a reference for engineering applications of the owl technology.
first_indexed 2024-12-19T23:54:59Z
format Article
id doaj.art-eef9d9a244a749b191b071964501a81b
institution Directory Open Access Journal
issn 2261-236X
language English
last_indexed 2024-12-19T23:54:59Z
publishDate 2017-01-01
publisher EDP Sciences
record_format Article
series MATEC Web of Conferences
spelling doaj.art-eef9d9a244a749b191b071964501a81b2022-12-21T20:01:02ZengEDP SciencesMATEC Web of Conferences2261-236X2017-01-011140300310.1051/matecconf/201711403003matecconf_2mae2017_03003Noise Generation of a Bionic Airfoil Based on Owl WingsGe Changjiang0College of Automotive Engineering, Jilin UniversityA bionic airfoil is used to investigate a preliminary understanding of the noise mechanism generated by the flow around the owl wing. The flow indicates a transitional separation bubble on the surface and the turbulent boundary layer reattaches at the downstream end of the bubble. This causes turbulent boundary layer trailing-edge scattering noise corresponding to the broadband noise of owl wings at low Reynolds numbers. Furthermore, a large-scale vortex detaches from the bubble and then drifts downstream. Thus, a tone will be generated by the vortex shedding. However, the computations of the acoustic field for both cases, where the on-body data surface and the off-body data surface are used respectively, predominantly verify the broadband nature of the noise that well agrees with the noise scattering caused by the turbulent boundary layer passing by the sharp trailing edge. Furthermore, the significant decrease of the spectra around 2k Hz is consistent with that of silent owl wings. This fact suggests that the numerical simulations are capturing the basic physical mechanism responsible for the noise radiated by the natural owl wing. This might be able to provide a reference for engineering applications of the owl technology.https://doi.org/10.1051/matecconf/201711403003
spellingShingle Ge Changjiang
Noise Generation of a Bionic Airfoil Based on Owl Wings
MATEC Web of Conferences
title Noise Generation of a Bionic Airfoil Based on Owl Wings
title_full Noise Generation of a Bionic Airfoil Based on Owl Wings
title_fullStr Noise Generation of a Bionic Airfoil Based on Owl Wings
title_full_unstemmed Noise Generation of a Bionic Airfoil Based on Owl Wings
title_short Noise Generation of a Bionic Airfoil Based on Owl Wings
title_sort noise generation of a bionic airfoil based on owl wings
url https://doi.org/10.1051/matecconf/201711403003
work_keys_str_mv AT gechangjiang noisegenerationofabionicairfoilbasedonowlwings