Super-resonances in a dielectric mesoscale sphere immersed in water: effects in extreme field localization of acoustic wave

We predict acoustic super resonance modes with a field-intensity enhancement several tens of thousands of times higher (order of magnitude: 104 -10 5) with the support of dielectric mesoscale spheres submerged in water, by means of numerical simulations. The super resonances are related to the internal dispersion in specific values of both Mie and particle material parameters, being responsible for the generation of giant fields within the particles and near its surface. Taking into account the analogy between electromagnetic and acoustic waves, this phenomenon is valid in the electromagnetic (optical) wave band.Rubio Michavila, C.; Minin, IV.; Minin, OV.; Uris Martínez, A. (2019). Super-resonances in a dielectric mesoscale sphere immersed in water: effects in extreme field localization of acoustic wave. Acoustical Society of America. 1-7. https://doi.org/10.1121/2.0001139S1

On the Role of the Geometrical Parameters in the Ultrasonic Transmission Through Plates with Subwavelength Holes Arrays

[EN] This paper presents an overview of the recents studies on the ultrasonic transmission through subwavelength holes arrays. The role of the geometrical parameters of the perforated plates in the transmission features has been reported by using a theoretical model under the rigid-solid assumption. It is shown that the transmission spectrum can be tailored by varying the geometrical parameters.This work has been supported by the Spanish MICINN (MAT2010-16879).Uris Martínez, A.; Gómez Lozano, V.; Candelas Valiente, P.; Belmar Ibáñez, F. (2014). On the Role of the Geometrical Parameters in the Ultrasonic Transmission Through Plates with Subwavelength Holes Arrays. Acta Acustica united with Acustica. 100(4):595-603. https://doi.org/10.3813/AAA.918739S595603100

Characterization of Sheep Wool as a Sustainable Material for Acoustic Applications

[EN] In recent years, natural materials are becoming a valid alternative to traditional sound absorbers due to reduced production costs and environmental protection. This paper reports the acoustical characterization of sheep wool. Measurements on normal incidence and diffuse-incidence sound absorption coefficients of different samples are reported. The airflow resistance has also been measured. The results prove that sheep wool has a comparable sound absorption performance to that of mineral wool or recycled polyurethane foam. An empirical model is used to calculate the sound absorption of sheep wool samples. A reasonable agreement on the acoustic absorption of all sheep wool samples is obtained.This work was financially supported by the project BIA2013-41537-R (BIAEFIREMAT "Development of new eco-materials and sustainable constructive solutions based on the use of waste and renewable raw materials"), funded by the Ministry of Economy and Competitiveness of Spain and co-financed with ERDF funds, within the National RDI Programme focused on the Challenges of Society 2013Rey Tormos, RMD.; Uris Martínez, A.; Alba, J.; Candelas Valiente, P. (2017). Characterization of Sheep Wool as a Sustainable Material for Acoustic Applications. Materials. 10(11):1-11. https://doi.org/10.3390/ma10111277S1111011Pinto, J., Cruz, D., Paiva, A., Pereira, S., Tavares, P., Fernandes, L., & Varum, H. (2012). Characterization of corn cob as a possible raw building material. Construction and Building Materials, 34, 28-33. doi:10.1016/j.conbuildmat.2012.02.014Briga-Sá, A., Nascimento, D., Teixeira, N., Pinto, J., Caldeira, F., Varum, H., & Paiva, A. (2013). Textile waste as an alternative thermal insulation building material solution. Construction and Building Materials, 38, 155-160. doi:10.1016/j.conbuildmat.2012.08.037Binici, H., Eken, M., Dolaz, M., Aksogan, O., & Kara, M. (2014). An environmentally friendly thermal insulation material from sunflower stalk, textile waste and stubble fibres. Construction and Building Materials, 51, 24-33. doi:10.1016/j.conbuildmat.2013.10.038Korjenic, A., Klarić, S., Hadžić, A., & Korjenic, S. (2015). Sheep Wool as a Construction Material for Energy Efficiency Improvement. Energies, 8(6), 5765-5781. doi:10.3390/en8065765Lopez Hurtado, P., Rouilly, A., Vandenbossche, V., & Raynaud, C. (2016). A review on the properties of cellulose fibre insulation. Building and Environment, 96, 170-177. doi:10.1016/j.buildenv.2015.09.031Lopez Hurtado, P., Rouilly, A., Raynaud, C., & Vandenbossche, V. (2016). The properties of cellulose insulation applied via the wet spray process. Building and Environment, 107, 43-51. doi:10.1016/j.buildenv.2016.07.017Binici, H., Aksogan, O., & Demirhan, C. (2016). Mechanical, thermal and acoustical characterizations of an insulation composite made of bio-based materials. Sustainable Cities and Society, 20, 17-26. doi:10.1016/j.scs.2015.09.004Asdrubali, F., Bianchi, F., Cotana, F., D’Alessandro, F., Pertosa, M., Pisello, A. L., & Schiavoni, S. (2016). Experimental thermo-acoustic characterization of innovative common reed bio-based panels for building envelope. Building and Environment, 102, 217-229. doi:10.1016/j.buildenv.2016.03.022Ballagh, K. O. (1996). Acoustical properties of wool. Applied Acoustics, 48(2), 101-120. doi:10.1016/0003-682x(95)00042-8Ersoy, S., & Küçük, H. (2009). Investigation of industrial tea-leaf-fibre waste material for its sound absorption properties. Applied Acoustics, 70(1), 215-220. doi:10.1016/j.apacoust.2007.12.005Oldham, D. J., Egan, C. A., & Cookson, R. D. (2011). Sustainable acoustic absorbers from the biomass. Applied Acoustics, 72(6), 350-363. doi:10.1016/j.apacoust.2010.12.009Berardi, U., & Iannace, G. (2015). Acoustic characterization of natural fibers for sound absorption applications. Building and Environment, 94, 840-852. doi:10.1016/j.buildenv.2015.05.029Mati-Baouche, N., de Baynast, H., Michaud, P., Dupont, T., & Leclaire, P. (2016). Sound absorption properties of a sunflower composite made from crushed stem particles and from chitosan bio-binder. Applied Acoustics, 111, 179-187. doi:10.1016/j.apacoust.2016.04.021Rwawiire, S., Tomkova, B., Militky, J., Hes, L., & Kale, B. M. (2017). Acoustic and thermal properties of a cellulose nonwoven natural fabric (barkcloth). Applied Acoustics, 116, 177-183. doi:10.1016/j.apacoust.2016.09.027López, J. P., El Mansouri, N.-E., Alba, J., Del Rey, R., Mutjé, P., & Vilaseca, F. (2012). ACOUSTIC PROPERTIES OF POLYPROPYLENE COMPOSITES REINFORCED WITH STONE GROUNDWOOD. BioResources, 7(4). doi:10.15376/biores.7.4.4586-4599Arenas, J. P., Rebolledo, J., Del Rey, R., & Alba, J. (2014). Sound Absorption Properties of Unbleached Cellulose Loose-Fill Insulation Material. BioResources, 9(4). doi:10.15376/biores.9.4.6227-6240Reixach, R., Del Rey, R., Alba, J., Arbat, G., Espinach, F. X., & Mutjé, P. (2015). Acoustic properties of agroforestry waste orange pruning fibers reinforced polypropylene composites as an alternative to laminated gypsum boards. Construction and Building Materials, 77, 124-129. doi:10.1016/j.conbuildmat.2014.12.041Del Rey, R., Alba, J., Ramis, J., & Sanchís, V. J. (2011). Nuevos materiales absorbentes acústicos obtenidos a partir de restos de botellas de plástico. Materiales de Construcción, 61(304), 547-558. doi:10.3989/mc.2011.59610Ramis, J., Alba, J., Del Rey, R., Escuder, E., & Sanchís, V. J. (2010). Nuevos materiales absorbentes acústicos basados en fibra de kenaf. Materiales de Construcción, 60(299), 133-143. doi:10.3989/mc.2010.50809Ingard, K. U., & Dear, T. A. (1985). Measurement of acoustic flow resistance. Journal of Sound and Vibration, 103(4), 567-572. doi:10.1016/s0022-460x(85)80024-9Dragonetti, R., Ianniello, C., & Romano, R. A. (2011). Measurement of the resistivity of porous materials with an alternating air-flow method. The Journal of the Acoustical Society of America, 129(2), 753-764. doi:10.1121/1.3523433Rey, R. del, Alba, J., Arenas, J. P., & Ramis, J. (2013). Technical Notes: Evaluation of Two Alternative Procedures for Measuring Airflow Resistance of Sound Absorbing Materials. Archives of Acoustics, 38(4), 547-554. doi:10.2478/aoa-2013-0064Rey, R. del, Alba, J., Arenas, J. P., & Sanchis, V. J. (2012). An empirical modelling of porous sound absorbing materials made of recycled foam. Applied Acoustics, 73(6-7), 604-609. doi:10.1016/j.apacoust.2011.12.009Delany, M. E., & Bazley, E. N. (1970). Acoustical properties of fibrous absorbent materials. Applied Acoustics, 3(2), 105-116. doi:10.1016/0003-682x(70)90031-

Angle-dependent ultrasonic transmission through plates with subwavelength hole arrays

Pdf con material suplementario.We study the angle and frequency dependence of sound transmission through water-immersed perforated aluminum plates. Three types of resonances are found to govern the acoustic properties of the plates: lattice resonances in periodic arrays, Fabry-Perot modes of the hole cavities, and elastic Lamb modes. The last two of them are still present in random arrays and have no parallel in optical transmission through holes. These modes are identified by comparing experiment with various levels of theoretical analysis, including full solution of the elasto-acoustic wave equations. We observe strong mixture of different transmission mechanisms, giving rise to unique acoustic behavior and opening new perspectives for exotic wave phenomena. © 2009 The American Physical SocietyThis work has been supported by the Spanish MCeI (MAT2006-03097, MAT2007-66050, and NanoLight.es) and the EU (NMP4-SL-2008-213669-ENSEMBLE).Peer Reviewe

Influence of the hole filling fraction on the ultrasonic transmission through plates with subwavelength aperture arrays

We report on the large impact of the hole filling fraction on the ultrasonic transmission spectra of periodic subwavelength hole arrays. We demonstrate both theoretically and experimentally that transmission peaks become narrower as the filling fraction decreases. Our results are consistent in plates with different thickness values and provide a route map for the design of plates with tailored acoustic transmission profiles. © 2008 American Institute of Physics.Peer Reviewe

Open Acoustic Barriers: A New Attenuation Mechanism

One of the main environmental problems of the industrialised countries is the noise, which can be defined as an unwanted or unpleasant outdoor sound generated by transport, industry and human activities in general. When it is not possible to reduce the emission of noise acting on the source, the reduction of noise levels in its transmission phase using acoustic screens (AS) seems appropriate; such screens are in common use to reduce noise levels and have been extensively studied since the middle of the 20th century. Over the last decades, various acoustic screen designs have been investigated to increase the screening effect. The research carried out focuses on both the reduction of diffraction at the top edge of the screen by varying the shape at the top or adding absorptive materials to the noise screen, but all these screens are basically formed by a continuum rigid material with a superficial density high enough, to reduce transmission of noise through the screen, in accordance with the mass law. At the end of the nineties, another type of screen based on arrangements of isolated scatterers embedded in air, emerged. Among other interesting properties, these screens provide new mechanisms to control the noise based on the Bragg law. First, a Sonic Crystal Acoustic Screen (SCAS) was presented, where the scatterers are arranged following crystalline patterns. After that, a new prototype of AS based on sonic crystals appears, which increases the attenuation capabilities using arrangements based on fractal geometries. The screens designed in this way have been referred to as Fractal-based Sonic Crystal Acoustic Screens (FSCAS) in this chapter. In both the cases, the mechanism that prevents the transmission of noise, and therefore increases the noise attenuation, is the destructive Bragg interference due to a multiple scattering process. Finally, a new concept of AS based on a periodic arrangement of scatterers, with a slit dimension between them that is smaller than the wavelength is introduced. This latest screen is called Subwavelength Slit Acoustic Screen (SSAS) which presents a Wood anomaly and Fabry-Perot resonances, being the destructive interferences among the scattered waves, responsible for the attenuation capabilities of these screens. This new kind of AS (SCAS, FSCAS and SSAS) presents interesting properties and can be considered as a real alternative to the classical AS, which are formed by a continuum rigid material. The aim of this chapter is to present these open AS, and it is organised as follows. In Section 1, an introduction about classic acoustic screens is presented. Numerical models and experimental set-up for the screens are introduced in Section 2. Then, in Section 3 the transmission properties of Sonic Crystals are explained, and the research advances in this field related to the design of a screen based on the new mechanism of noise control are highlighted. The definition and development of the Fractal-based Sonic Crystal Acoustic Screen are shown subsequently. The Subwavelength Slit Acoustic Screen is developed in Section 4. Finally, in Section 5 the main results and conclusions of the work are presented

Ultrasonic focusing with mesoscale polymer cuboid

[EN] In this paper, we demonstrate that, contrary to what the Geometrical Optics laws dictate, a flat polymer mesoscale cuboid immersed in water with no need of negative refraction can focus sound. Two main polymers were considered and lens parameters compared: PMMA and Rexolite®. It was concluded that Rexolite® is preferable for acoustic jet formation. The nature of the formation of the foci along the longitudinal axis, that is to say along the wave propagation axis, is numerically and experimentally demonstrated. In addition, the conditions under which a cubic particles lens of this type forms a single localized region with a sub-diffraction transverse size (approximately 0.44 wavelength) are determined. The comparisons of the acoustic wave pressures and the focal distance between the Finite Element Method based numerical results and the experimental results show fair agreement.This work has been supported by Spanish Ministry of Science, Innovation and Universities (grant No. RTI2018-100792-B-I00). The research was partially supported by Tomsk Polytechnic University Competitiveness Enhancement Program.Tarrazó-Serrano, D.; Rubio Michavila, C.; Minin, OV.; Uris Martínez, A.; Minin, IV. (2020). Ultrasonic focusing with mesoscale polymer cuboid. Ultrasonics. 106:1-5. https://doi.org/10.1016/j.ultras.2020.1061431510

Enhancement of pupil-masked wavelength-scale gas-filled flat acoustic lens based on anomaly apodization effect

[EN] In this letter, the improvement in focus by the use of a pupil mask produced in an acoustic mesoscale cuboid particle ¿lled with CO2 is reported. Thereby, the result shows that the pupil mask increases the sound intensity and also increases the resolution (or a reduction of the full width at half maximum, FWHM) in focus compared to the non-masked one. These results are important because they con¿rm the effect of abnormal amplitude apodization for a one-wavelength dimension acoustic lens and demonstrate that it is possible to improve sound focusing of a cuboid gas-¿lled lens with one wavelength dimension. This is the smallest size of an acoustic lens ever considered in this type of literature, with side dimensions of the cube equal to one wavelength and a diameter to focus ratio of 2.5, the sound ampli¿cation in focus is 5.4 dB at 4125 Hz, with the resolution near to the diffraction limit.This work has been supported by TEC2015-70939-R (MINECO/FEDER). The research was partially supported by Tomsk Polytechnic University Competitiveness Enhancement Program.Rubio Michavila, C.; Tarrazó-Serrano, D.; Minin, OV.; Uris Martínez, A.; Minin, IV. (2019). Enhancement of pupil-masked wavelength-scale gas-filled flat acoustic lens based on anomaly apodization effect. Physics Letters A. 383:396-399. https://doi.org/10.1016/j.physleta.2018.11.014S39639938

Experimental Ultrasound Transmission through Fluid-Solid and Air-Solid Phononic Plates

[EN] Underwater ultrasonic transmissions for fluid-solid and air-solid phononic brass plates are reported in this work. Although the structure is roughly the same, experimental results show very different behaviour between fluid-solid and air-solid phononic plates, due to most of the properties of the fluid-solid perforated plates rely on Fabry-Perot resonances,Wood anomalies and Lamb modes. In air-solid phononic plates Fabry-Perot resonance is highly attenuated due to impedances difference between air and water, and therefore some transmission modes are now distinguishable due to surface modes coupling.This work has been supported by Spanish MINECO (TEC2015-70939-R) and Generalitat Valenciana (AICO/2015/119).Gómez Lozano, V.; Rubio Michavila, C.; Candelas Valiente, P.; Uris Martínez, A.; Belmar Ibáñez, F. (2016). Experimental Ultrasound Transmission through Fluid-Solid and Air-Solid Phononic Plates. Materials. 9(453):1-8. https://doi.org/10.3390/ma9060453S18945