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Constantin Sandu, Andrei-George Totu, Andrei-Tudor Trifu and Marius Deaconu
This paper presents the technological advancement of using friction powders to increase the absorption of acoustic liners used in the reduction of tonal noise generated by aero-engines or for other applications related to Helmholtz resonators used in noi...
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Moritz Neubauer, Julia Genßler, Vincent Radmann, Fleming Kohlenberg, Michael Pohl, Kurt Böhme, Karsten Knobloch, Ennes Sarradj, Klaus Höschler, Niels Modler and Lars Enghardt
This paper presents a combined experimental and numerical investigation on a novel liner concept for enhanced low-frequency and broadband acoustic attenuation. In particular, two different realizations, derived from conventional Helmholtz resonators (HR)...
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Abhishek Gautam, Alper Celik and Mahdi Azarpeyvand
The use of acoustic liners, based on double-degree-of-freedom Helmholtz resonators, for low-frequency-noise attenuation is limited by the volume of individual resonating cavities. This study investigates the effect of the septum neck length on the acoust...
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Sergey Alekseev, Natalia Polzikova and Valery Luzanov
The hybrid high overtone bulk acoustic wave resonators (HBARs) consisting of a piezoelectric film transducers and gallium gadolinium garnet substrates with yttrium iron garnet films (YIG-GGG-YIG) are used for experimental excitation and detection of acou...
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Alexey Abdrashitov, Alexander Gavrilov, Evgeny Marfin, Vladimir Panchenko, Andrey Kovalev, Vadim Bolshev and Julia Karaeva
One of the most well-known methods of intensifying the process of anaerobic digestion is the pretreatment of raw materials. For the first time, the use of a jet-driven Helmholtz oscillator for biomass pretreatment is proposed. The design of the device is...
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Nikolay Kanev
Metasurfaces formed by monopole and dipole resonators are studied theoretically. The monopole resonators are Helmholtz resonators or membranes vibrating on the first eigenfrequency; the dipole ones are spheres on springs or membranes vibrating on the sec...
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Vadim Palchikovskiy, Igor Khramtsov and Oleg Kustov
This article considers the influence of the orifice arrangement in a cover of a cylindrical resonator on the impedance determined by the Dean?s method. A resonator with a small height and a low perforation degree is studied. This geometry provides differ...
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Alexandr Komkin, Aleksei Bykov and Olga Saulkina
Methods for measuring the acoustic characteristics of orifices have been reviewed. Comparison of three methods for evaluating of oscillation velocity in the neck of the Helmholtz resonator are presented. The first method is measurements in an impedance t...
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Sourabh Dogra and Arpan Gupta
Acoustic metamaterials are materials artificially engineered to control sound waves, which is not possible with conventional materials. We have proposed a design of an acoustic metamaterial plate with inbuilt Helmholtz resonators. The plate is made of Po...
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Yiming Jiang, Tie Zhang, Gaoxuan Wang and Sailing He
A dual-gas photoacoustic spectroscopy (PAS) sensor based on wavelength modulation spectroscopy (WMS) was developed and experimentally demonstrated. Distributed feedback (DFB) laser diodes, emitting at 1512 and 1653 nm, were utilized as the excitation sou...
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