Results 31 to 40 of about 1,760,515 (295)

Experimental Characterization and Analytical Modelling of Rotor Tonal Noise

, 2020
In this study, the tonal noise due to the interaction ofa simplified rotor and a circular tower is characterized experimentally in a controlled environment. The test bench isinstalled in the anechoic chamber of ENSTA Paris, and is composed of a rotor made of three NACA 0012 untwisted blades set into motion by a motor.
Cotté, Benjamin, Rigall, Tommy, Deora, Chakshu   +2 more
openaire   +3 more sources

Reducing Tonal Noise in IPMSM Vehicle Drives Through Harmonic Injection

IEEE Transactions on Transportation Electrification
PMSM drives are widely used in powertrains for hybrid and battery electric vehicles. Tonal noise radiation of the drive results from magnetic force excitations in the air gap of the machine.
T. Windisch, M. Burkhardt, J. Troge, W. Drossel   +3 more
semanticscholar   +1 more source

Soundscape and ambient noise levels of the Arctic waters around Greenland

Scientific Reports, 2021
A longer Arctic open water season is expected to increase underwater noise levels due to anthropogenic activities such as shipping, seismic surveys, sonar, and construction. Many Arctic marine mammal species depend on sound for communication, navigation,
Michael Ladegaard, Jamie Macauley, Malene Simon, Kristin L. Laidre, Aleksandrina Mitseva, Simone Videsen, Michael Bjerre Pedersen, Jakob Tougaard, Peter Teglberg Madsen   +8 more
doaj   +1 more source

Waveguide invariant estimation based on correlation coefficient of tonal acoustic intensity interference fluctuation

Xibei Gongye Daxue Xuebao, 2023
The waveguide invariant is usually not extracted from the striation pattern of broadband continuous spectrum in the low frequency analysis and recording spectrum at low signal-to-noise ratio.
YAO Yuan, SUN Chao, LIU Xionghou, LI Mingyang   +3 more
doaj   +1 more source

Effect of serrated trailing edges on aerofoil tonal noise

Journal of Fluid Mechanics, 2020
A wall-resolved large-eddy simulation of a symmetric Joukowski aerofoil with a 12 % thickness at a Reynolds number of 250 000, a Mach number of 0.4 and zero incidence angle is performed in order to investigate the effect of using a serrated trailing edge
Matthieu B. R. Gelot, J. Kim
semanticscholar   +1 more source

Comparison between android applications and Class-I sound level meters in SPL measurement performance

Acta Acustica
Accurate measurement of sound pressure level (SPL) is a cornerstone for understanding acoustic communication, animal behavior, and ecological dynamics. Acoustic signals can be broadly categorized into broadband and tonal sounds.
Sasindran Shwetha, Devanand Nambukalithoppil, Srinivas Chelakkara Lakshmanan, Deb Rittik   +3 more
doaj   +1 more source

Optimization of open counter – rotation fan blades on the basis of solving a 3D Navier-Stokes inverse problem with the aim of reducing tonal noise

Вестник Самарского университета: Аэрокосмическая техника, технологии и машиностроение, 2018
The paper presents some results of gas-dynamic and aero-acoustic optimization of the blade profile of an unducted counter-rotation fan (CRF) by using a 3D inverse problem.
V. I. Mileshin, A. A. Rossikhin, S. V. Pankov, S. K. Shchipin   +3 more
doaj   +1 more source

Gate‐Programmable Linearization of Atomically Thin Nanoelectromechanical Resonators via Duffing Nonlinearity Cancellation

Advanced Functional Materials, EarlyView.
Gate bias is used to cancel Duffing nonlinearity in atomically thin MoS2 drumhead resonators, switching their response from hardening to softening and creating a nearly linear operating point. This electrical control suppresses hysteresis, enables stronger linear drive, and improves signal‐to‐noise ratio, offering a practical route to stable 2D NEMS ...
Pengcheng Zhang, Miroslav Haluska, Cosmin Roman, Christofer Hierold   +3 more
wiley   +1 more source

Aeroacoustic Prediction and Optimization of Unevenly Spaced Blades in Axial Fans

International Journal of Turbomachinery, Propulsion and Power
A common solution for reducing the tonal noise annoyance caused by fans is to change the circumferential blade spacing from even to uneven. However, this technique requires predictive tools to simulate and assess their acoustic performance at a lower ...
Samir Assaf, Thibaut Gras, Jacques Ferhat   +2 more
doaj   +1 more source

Bioinspired Adaptive Sensors: A Review on Current Developments in Theory and Application

Advanced Materials, EarlyView.
This review comprehensively summarizes the recent progress in the design and fabrication of sensory‐adaptation‐inspired devices and highlights their valuable applications in electronic skin, wearable electronics, and machine vision. The existing challenges and future directions are addressed in aspects such as device performance optimization ...
Guodong Gong, You Zhou, Qingxiu Li, Wenyu Zhao, Sunyingyue Geng, Hangfei Li, Yan‐Bing Leng, Shirui Zhu, Guanglong Ding, Yongbiao Zhai, Ziyu Lv, Ye Zhou, Su‐Ting Han   +12 more
wiley   +1 more source