Results 11 to 20 of about 1,130 (256)
Reduction of ear-position sound pressure at low speed in electric vehicles by pulp mold
Nihon Kikai Gakkai ronbunshu, 2022 Electric vehicles (EVs) generate different cabin noise from internal combustion engine vehicles (ICE) during low-speed driving. In order to identify the cause of the interior noise of EVs at low-speed (30km/h) and to reduce the noise, a Helmholtz ...
Sachito NAKANO +3 more
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Superfluid Helmholtz Resonators [PDF]
The Journal of the Acoustical Society of America, 1966 The equations governing the resonances of a superfluid in a Helmholtz resonator have been developed. Four cases are considered: (1) when the entire resonator is packed with a superleak; (2) when only the neck is packed with superleak; (3) when only the volume is packed with the superleak; (4) when no superleak is present.
Michael A. Kriss +2 more
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Giraffe Helmholtz resonance [PDF]
The Journal of the Acoustical Society of America, 2013 Many animal species, including elephants and okapi, use sounds above and below the range of human hearing to communicate. A longitudinal study presented here suggests giraffe produce infrasonic vocalizations using Helmholtz resonance. Recordings were made of giraffe (Giraffe camelopardalis) in controlled indoor conditions and naturalistic outdoor ...
Elizabeth vonMuggenthaler +1 more
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Modal damping ratios of the two-degree-of-freedom acoustic model having a Helmholtz resonator
Nihon Kikai Gakkai ronbunshu, 2016 Helmholtz resonators are used in many industrial products as devices for reducing low-frequency noise. An advantage of the Helmholtz resonator is that the structure is simple and applicable to low-frequency noise for its size.
Shinichi MARUYAMA +2 more
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Conference Room Reverberation Time Correction Using Helmholtz Resonators Lined with Absorbers
Shock and Vibration, 2014 Echo and sound resonance in a conference room cause obscure speech and make listeners tired. Thus, the acoustical properties of a conference room are vitally important. The conference room 412 at Sharif University
Hossein Namvar Arefi +7 more
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Incorporation of Resonators Into Plenum Window
Archives of Acoustics, 2018 A plenum window with incorporation of Helmholtz resonators in between two glass panes was tested in a reverberation room. The effects of jagged flap on reducing strength of diffracted sound was also investigated in the present studies where white ...
Hsiao Mun LEE +4 more
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Journal of Low Frequency Noise, Vibration and Active Control, 2021 In this work, modified designs of Helmholtz resonators with extended deflected neck are proposed, numerically evaluated and optimized aiming to achieve a better transmission loss performance over a broader frequency range.
Weiwei Wu, Yiheng Guan
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Characteristics of partially filled Helmholtz resonators
Acta Acustica, 2023 In this work we have developed a technique for the measurement of the resonance curve of Helmholtz resonators as a function of filling with beads and sands of different sizes, and water as the reference.
Indenbom Mikhail V., Pogossian Souren P.
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Comptes Rendus. Physique, 2021 In this review, we present the results on sub-wavelength perfect acoustic absorption using acoustic metamaterials made of Helmholtz resonators with different setups.
Romero-García, V. +8 more
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Extraordinary acoustic transmission mediated by Helmholtz resonators
AIP Advances, 2014 We demonstrate perfect transmission of sound through a rigid barrier embedded with Helmholtz resonators. The resonators are confined within a waveguide and they are oriented such that one neck protrudes onto each side of the barrier.
Vijay Koju +2 more
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