Results 21 to 30 of about 1,760,515 (295)

Control of trailing-edge noise from airfoil using a plasma actuator

open access: yesJournal of Fluid Science and Technology, 2018
Control of noise generation at an airfoil trailing-edge was conducted using a plasma actuator for an NACA0012 airfoil with an angle of attack of -2° at a chord Reynolds number Re = 1.6×105, where the boundary-layer instability on the pressure side was ...
Ayumu INASAWA, Yui KAGAWA
doaj   +1 more source

Aeroacoustics Assessment of an Hybrid Aircraft Configuration with Rear-Mounted Boundary Layer Ingested Engine

open access: yesApplied Sciences, 2021
Hybrid electric propulsion is a promising solution to reduce aircraft emissions, thus improving the sustainability of the air transport. In this work, a hybrid aircraft configuration with a rear-mounted boundary layer ingestion (BLI) engine has been ...
Francesco Petrosino   +2 more
doaj   +1 more source

Evaluation of the Audibility Boundaries of Multirotor Systems of Different Configurations [PDF]

open access: yesE3S Web of Conferences, 2023
The paper proposes a method for calculating the limits of audibility of multirotor systems such as quad- and hexacopters. The components of the proposed methodology are data on the noise of the device and the ambient noise, as well as the criterion of ...
Moshkov Petr, Timushev Sergey
doaj   +1 more source

Tonal and Band Noise Tinnitus

open access: yesPractica Oto-Rhino-Laryngologica, 1983
In this paper, clinical characteristics of 3 kinds of tinnitus, i.e. tonal, band noise and tonal with noise background were analysed. Results were as follows:1) Out of 187 patients with tinnitus, 109 had band noise, 64 had tonal and 14 had tonal with noise background.2) Residual inhibition was observed in 64% of patients with band noise tinnitus and 49%
Kitahara, Masaaki   +5 more
openaire   +2 more sources

A wavelet-based separation method for tonal and broadband components of low Reynolds-number propeller noise

open access: yesMeasurement science and technology, 2023
Propeller noise generally exhibits a rich mixture of tonal and broadband components related to different physical mechanisms. Specifically, the tones are characterized by having deterministic and persistent characteristics, while the broadband ...
S. Meloni   +6 more
semanticscholar   +1 more source

The influence of booster design features on aicraft engine fan tonal noise

open access: yesВестник Самарского университета: Аэрокосмическая техника, технологии и машиностроение, 2016
Fan and booster tonal noise makes significant contribution to the overall noise level of an aero engine, particularly in subsonic modes of operation.
Yu. D. Khaletskiy   +2 more
doaj   +1 more source

Increased Right Frontal Brain Activity During the Mandarin Hearing-in-Noise Test

open access: yesFrontiers in Neuroscience, 2020
PurposePrevious studies have revealed increased frontal brain activation during speech comprehension in background noise. Few, however, used tonal languages.
Fengxiang Song   +11 more
doaj   +1 more source

Calculation of Total Tone-to-Noise Ratio and Total Prominence Ratio for Small Fan Noise and Determination of Subjective Annoyance Thresholds

open access: yesInternational Journal of Turbomachinery, Propulsion and Power
Fan noise from small cooling fans often contains multiple coexisting tonal components whose combined perceptual impact cannot be fully represented by conventional single-tone metrics.
Takefumi Nakano, Gaku Minorikawa
doaj   +1 more source

Smart Blade Count Selection to Align Modal Propagation Angle with Stator Stagger Angle for Low-Noise Ducted Fan Designs

open access: yesAerospace
The rotor–stator interaction noise is a major source of fan noise. Especially for low-speed fan stages, the tonal component is typically a dominant noise source.
Stephen Schade   +3 more
doaj   +1 more source

Phase Synchronisation for Tonal Noise Reduction in a Multi-Rotor UAV

open access: yesDrones
This study aims to investigate the effects of phase synchronisation on tonal noise reduction in a multi-rotor UAV using an electronic phase-locking system.
B. B. Turhan, D. Rezgui, M. Azarpeyvand
semanticscholar   +1 more source

Home - About - Disclaimer - Privacy