Artykuły w czasopismach: „Vibro-acoustic Wave”

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Zhao, Nan, Linsheng Huo i Gangbing Song. "A nonlinear ultrasonic method for real-time bolt looseness monitoring using PZT transducer–enabled vibro-acoustic modulation". Journal of Intelligent Material Systems and Structures 31, nr 3 (4.12.2019): 364–76. http://dx.doi.org/10.1177/1045389x19891534.

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A real-time nonlinear ultrasonic method based on vibro-acoustic modulation is applied to monitor early bolt looseness quantitatively by using piezoceramic transducers. In addition to the ability to detect the early bolt looseness, a major contribution is that we replaced the shaker, which is commonly used in a vibro-acoustic modulation method, by a permanently installed and low-cost lead zirconate titanate patch. In vibro-acoustic modulation, when stimulating two input waves with distinctive frequencies, namely the high-frequency probing wave and the low-frequency pumping wave, the high-frequency probing wave will be modulated by the low-frequency pumping wave to generate sidebands in terms of bolt looseness. Thus, the influence of low-frequency voltage amplitudes on the modulation results, which is ambiguous in previous research, is also analyzed in this article. The results of experiment demonstrated that the lead zirconate titanate–enabled vibro-acoustic modulation method is reliable and easy to implement to identify the bolt looseness continuously and quantitatively. In addition, low-frequency amplitudes of actuating voltage should be selected in a reasonable range. Finally, we compared the vibro-acoustic modulation method with the time-reversal method based on the linear ultrasonic theory, and the result illustrates that vibro-acoustic modulation method has better performance in monitoring the early bolt looseness.

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Tebyanian, Afshin, i Mohammad Reza Ghazavi. "Vibro-acoustic and sound transmission loss analysis of truncated conical shell subjected to incident sound wave". Journal of Vibration and Control 25, nr 2 (29.06.2018): 435–44. http://dx.doi.org/10.1177/1077546318783553.

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A combination of analytical method for shell vibration, boundary element method (BEM) for acoustic media of shell outer space, and finite element method (FEM) for shell inner space was used to study the vibro-acoustic behavior and extract sound transmission loss factor (STL) of a coupled vibro-acoustic system. The equation of motion of the shell is extracted based on the Donnell–Mushtari hypothesis and using Hamilton principles. The acoustic pressure on the outer and inner space is obtained using BEM on the defined nodes on the surface and these localized nodal pressures are converted to nodal concentrated forces. Finally, vibration of the coupled vibro-acoustic model is solved in frequency domain and vibration response of shell and acoustic pressure at any point in the media (outer, on the surface, and inner of shell) are obtained. Also, the STL of the shell is extracted based on the ratio of total acoustic energy received by the shell to that transferred to inner space.

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Włodarska, Dorota, Andrzej Klepka, Wieslaw Jerzy Staszewski i Tadeusz Uhl. "Comparative Study of Instantaneous Frequency Extraction in Nonlinear Acoustics Used for Structural Damage Detection". Key Engineering Materials 588 (październik 2013): 33–42. http://dx.doi.org/10.4028/www.scientific.net/kem.588.33.

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Nonlinear acoustics deals with various nonlinear effects that occur in ultrasonic wave propagation. The method is suitable for material characterisation, as it uses different nonlinear phenomena associated with material imperfections. The method has been used for detecting nonlinearities in cracked solids by: measuring distortions of acoustic signals, estimating resonance frequency shifts or assessing nonlinear vibro-acosutic modulations. The latter is the most widely used non-classical approach to probe material nonlinearities. The method involves vibro-acoustic interactions of ultrasonic wave and modal vibration in damaged specimens. Modulation intensity that strongly relates to damage severity - is usually assessed in the frequency domain and often leads to confusing results when large modulations are involved. The paper investigates the time domain analysis of vibro-acoustic modulated signals. Several methods for instantaneous frequency calculation used to assess the intensity of modulation - are compared. Simulated and experimental data are used in these investigations.

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Volkov, Konstantin. "Coupled Simulation of Fluid Flow and Vibro-Acoustic Processes in the Channel with a Circular Cylinder". Fluids 7, nr 12 (11.12.2022): 382. http://dx.doi.org/10.3390/fluids7120382.

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Vibro-acoustic processes are an interacting set of pulsations of the working fluid and vibrations of mechanical structural elements. The simulation of vibro-acoustic processes in a long pipe with an elastic round cylinder is considered. The mathematical model is developed in a coupled formulation, when not only pressure pulsations cause pipe vibrations, but also vibrations of the mechanical subsystem affect sound wave propagation in the working fluid. The influence of vortex formation processes in the channel on the system dynamics is taken into account. The fluid flow is found using delayed detached eddy simulation. The flow regimes around a single round cylinder corresponding to various Reynolds numbers are investigated to validate the computational algorithm. The distributions of the flow quantities and vibro-acoustic behavior of the system are discussed.

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Wang, Xian-Zhong, Quan-Zhou Jiang, Ye-Ping Xiong i Xin Gu. "Experimental studies on the vibro-acoustic behavior of a stiffened submerged conical-cylindrical shell subjected to force and acoustic excitation". Journal of Low Frequency Noise, Vibration and Active Control 39, nr 2 (9.05.2019): 280–96. http://dx.doi.org/10.1177/1461348419844648.

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An experimental model was made to investigate the influence of force and acoustic excitation on the vibration and underwater sound radiation of the stiffened conical-cylindrical shell. Meanwhile, a coupled precise transfer matrix method and wave superposition method was also proposed to analyze vibro-acoustic responses of combined shells. To test accuracy of the present method, vibration and acoustic results of combined shells are firstly examined. As expected, results of present method are in excellent agreement with the ones in literature and model test. The experimental results show that free vibrations of the experimental test are consistent with the literature data and the present method’s results. Forced vibration and acoustic test results are also well agreed with the numerical results from the coupled precise transfer matrix method/wave superposition method. The comparisons show that the coupled precise transfer matrix method/wave superposition method is reliable and credible to solve the vibro-acoustic response of combined shells. The analysis shows that the acoustic excitation is the key factor for radiated noise in low-frequency range. However, the radiated noise resulted from force excitation is dominant in mid-high frequency band.

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Klepka, Andrzej, Wieslaw Jerzy Staszewski, T. Uhl, Dario di Maio, Fabrizio Scarpa i K. F. Tee. "Impact Damage Detection in Composite Chiral Sandwich Panels". Key Engineering Materials 518 (lipiec 2012): 160–67. http://dx.doi.org/10.4028/www.scientific.net/kem.518.160.

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This paper demonstrates impact damage detection in a composite sandwich panel. The panel is built from a chiral honeycomb and two composite skins. Chiral structures are a subset of auxetic solids exhibiting counterintuitive deformation mechanism and rotative but not reflective symmetry. Damage detection is performed using nonlinear acoustics,involves combined vibro-acoustic interaction of high-frequency ultrasonic wave and low-frequency vibration excitation. High-and low-frequency excitations are introduced to the panel using a low-profile piezoceramic transducer and an electromagnetic shaker, respectively. Vibro-acoustic modulated responses are measured using laser vibrometry. The methods used for impact damage detection clearly reveal de-bonding in the composite panel. The high-frequency weak ultrasonic wave is also modulated by the low-frequency strong vibration wave when nonlinear acoustics is used for damage detection. As a result frequency sidebands can be observed around the main acoustic harmonic in the spectrum of the ultrasonic signal.

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Liu, Habibi, Chai, Wang i Chen. "A Numerical Study of Axisymmetric Wave Propagation in Buried Fluid-Filled Pipes for Optimizing the Vibro-Acoustic Technique when Locating Gas Pipelines". Energies 12, nr 19 (27.09.2019): 3707. http://dx.doi.org/10.3390/en12193707.

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Buried pipeline systems play a vital role in energy storage and transportation, especially for fluid energies like water and gas. The ability to locate buried pipes is of great importance since it is fundamental for leakage detection, pipeline maintenance, and pipeline repair. The vibro-acoustic locating method, as one of the most effective detection technologies, has been studied by many researchers. However, previous studies have mainly focused on vibro-acoustic propagation in buried water pipes. Limited research has been conducted on buried gas pipes. In this paper, the behavior of gas-dominated wave motion will be investigated and compared against water-dominated wave motion by adapting an established analytical model of axisymmetric wave motion in buried fluid-filled pipes. Furthermore, displacement profiles in spatial domain resulting from gas-dominated wave in buried gas pipeline systems will be analyzed, and the effects of pipe material, soil property, as well as mode wave type will be discussed in detail. An effective radiation coefficient (ERC) is proposed to measure the effective radiation ability of gas-dominated wave and water-dominated wave. It is observed that the gas-dominated wave in gas pipes cannot radiate into surrounded soil as effectively as water-dominated wave in water pipes because of the weak coupling between gas and pipe-soil. In this case, gas-dominated wave may not be the best choice as the target wave for locating buried gas pipes. Therefore, the soil displacements result from the shell-dominated wave are also investigated and compared with those from gas-dominated wave. The results show that for buried gas pipes, the soil displacements due to radiation of shell-dominated wave are stronger than gas-dominated wave, which differs from buried water pipe. Hence, an effectively exciting shell-dominated wave is beneficial for generating stronger vibration signals and obtaining the location information. The findings of this study provide theoretical insight for optimizing the current vibro-acoustic method when locating buried gas pipes.

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WANG, YI, SIPING CHEN, TIANFU WANG, TING ZHOU, QIAOLIANG LI, YI ZHENG i XIN CHEN. "DEVELOPMENT OF A GENERIC ULTRASOUND VIBRO-ACOUSTIC IMAGING PLATFORM FOR TISSUE ELASTICITY AND VISCOSITY". Journal of Innovative Optical Health Sciences 05, nr 01 (styczeń 2012): 1250002. http://dx.doi.org/10.1142/s1793545812500022.

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Tissue elasticity and viscosity are always associated with pathological changes. As a new imaging method, ultrasound vibro-acoustic imaging is developed for quantitatively measuring tissue elasticity and viscosity which have important significance in early diagnosis of cancer. This paper developed an ultrasound vibro-acoustic imaging research platform mainly consisting of excitation part and detection part. The excitation transducer was focused at one location within the medium to generate harmonic vibration and shear wave propagation, and the detection transducer was applied to detect shear wave at other locations along shear wave propagation path using pulse-echo method. The received echoes were amplified, filtered, digitized and then processed by Kalman filter to estimate the vibration phase. According to the phase changes between different propagation locations, we estimated the shear wave speed, and then used it to calculate the tissue elasticity and viscosity. Preliminary phantom experiments based on this platform show results of phantom elasticity and viscosity close to literature values. Upcoming experiments are now in progress to obtain quantitative elasticity and viscosity in vitro tissue.

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Pieczonka, Łukasz, Wieslaw Jerzy Staszewski i Tadeusz Uhl. "Investigation of Nonlinear Vibro-Acoustic Wave Modulation Mechanisms in Composite Laminates". Key Engineering Materials 569-570 (lipiec 2013): 96–102. http://dx.doi.org/10.4028/www.scientific.net/kem.569-570.96.

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This paper investigates the effect of low-frequency vibration and the related temperature field on nonlinear vibro-acoustic wave modulations. Experimental modal analysis was used to find natural frequencies and mode shapes of a composite laminate plate with seeded delamination. Temperature distribution was analyzed with a thermographic camera in the vicinity of damage for the identified vibration modes. These frequencies of these vibration modes were then used for low-frequency excitation in nonlinear acoustic tests. The correlation between the thermal field and the observed wave modulations was analyzed.

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Koo, Kunmo, Bert Pluymers, Wim Desmet i Semyung Wang. "Vibro-acoustic design sensitivity analysis using the wave-based method". Journal of Sound and Vibration 330, nr 17 (sierpień 2011): 4340–51. http://dx.doi.org/10.1016/j.jsv.2011.03.030.

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Pieczonka, L., L. Zietek, A. Klepka, W. J. Staszewski, F. Aymerich i T. Uhl. "Damage imaging in composites using nonlinear vibro-acoustic wave modulations". Structural Control and Health Monitoring 25, nr 2 (16.07.2017): e2063. http://dx.doi.org/10.1002/stc.2063.

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Essahbi, Soufien, Emmanuel Perry‐Debain, Mohamed Haddar, Lotfi Hammami i Mabrouk Ben Tahar. "On the use of the plane wave based method for vibro‐acoustic problems". Multidiscipline Modeling in Materials and Structures 7, nr 4 (15.11.2011): 356–69. http://dx.doi.org/10.1108/15736101111185261.

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PurposeThe purpose of this paper is to present the extension of plane wave based method.Design/methodology/approachThe mixed functional are discretized using enriched finite elements. The fluid is discretized by enriched acoustic element, the structure by enriched structural finite element and the interface fluid‐structure by fluid‐structure interaction element.FindingsResults obtained show the potentialities of the proposed method to solve a much larger class of wave problems in mid‐ and high‐frequency ranges.Originality/valueThe plane wave based method has previously been applied successfully to finite element and boundary element models for the Helmholtz equation and elastodynamic problems. This paper describes the extension of this method to the vibro‐acoustic problem.

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Ben Souf, M. A., D. Chronopoulos, M. Ichchou, O. Bareille i M. Haddar. "On the Variability of the Sound Transmission Loss of Composite Panels Through a Parametric Probabilistic Approach". Journal of Computational Acoustics 24, nr 01 (marzec 2016): 1550018. http://dx.doi.org/10.1142/s0218396x15500186.

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A robust model for the prediction of the variability of the vibro-acoustic response is presented in this paper. The dynamic response of composite panels is treated using a Statistical Energy Analysis (SEA) approach. One of the basic input parameters is the propagating flexural wavenumber of the modeled panel. The Wave Finite Element Method (WFEM) is used to investigate the dispersion characteristics of the layered panel. It is based on the evaluation of the mass and the stiffness matrices of a periodic segment of the structure. A polynomial eigenvalue problem is then formed for calculating the wavenumbers and the wave mode shapes. The main novelty in this paper consists in evaluating the influence of the variability of the mechanical parameters of the composite panel on its vibro-acoustic response, that is on its sound transmission loss (STL). This influence is quantified using the generalized polynomial chaos expansion. The efficiency of the approach is exhibited for isotropic and orthotropic panels.

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Liu, Bin, Zhiwei Luo i Tie Gang. "Influence of low-frequency parameter changes on nonlinear vibro-acoustic wave modulations used for crack detection". Structural Health Monitoring 17, nr 2 (24.01.2017): 218–26. http://dx.doi.org/10.1177/1475921716689385.

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The use of vibro-acoustic modulation is an effective nonlinear and nondestructive approach to the detection and monitoring of cracks in fatigued, defective, and fractured materials. However, the vibro-acoustic modulation results strongly depend on choice of the testing parameters. To implement this technique for additional applications, the effect of variation in the test parameters must be well understood. This study investigates the influence of variation in the amplitude and frequency of pumping (low-frequency vibration) signals on the modulation. We apply two kinds of probing excitations, sine-wave and swept-signal excitations, and we measure the modulation intensity variation with changes in the relevant parameters to observe their influence on the modulations. Dynamic strain measurement of the crack area is utilized to analyze the relation between the degree of crack opening/closing and the modulation on the crack interface. The results indicate that the probing amplitude has little effect on the modulation, and furthermore, the sweep-signal excitation technique can be used to select the proper probing frequency. The results also indicate that there is a critical pumping strain value ( εc) for the crack samples. When the pumping strain reaches this critical value, the modulation reaches a maximum. However, the opening/closing area cannot increase any more even if the pumping amplitude further increases, and thus, the modulation does not change. The extent of the crack opening/closing also varies with the pumping frequency. Our results suggest that increased sensitivity to crack detection can be achieved with the use of the resonance frequency as the pumping frequency in vibro-acoustic modulation tests.

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Ghinet, Sebastian, i Noureddine Atalla. "VIBRO-ACOUSTIC BEHAVIORS OF FLAT SANDWICH COMPOSITE PANELS". Transactions of the Canadian Society for Mechanical Engineering 30, nr 4 (grudzień 2006): 473–93. http://dx.doi.org/10.1139/tcsme-2006-0030.

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The main objective of this paper is to present a theoretical approach to model the vibro-acoustic behavior of flat sandwich composite panels. Two models are studied: symmetrical laminate composite and sandwich composite panel. The theories are developed in a wave approach context. It is shown that a discrete layers sandwich composite panel modeling type leads to a 12th order relation of dispersion while a laminate composite panel modeling leads to a 6th order relation of dispersion. The two models give similar results at low frequencies but the modeling of a sandwich panel using the laminate panel theory leads to inaccuracies at high frequencies. The dispersion relations are first solved in the context of generalized polynomial complex eigenvalues problems. Next, the dispersion relations are used to derive the analytical expression of the critical frequencies and to calculate the natural frequencies of the panel. Using the dispersion relation’s solutions, the study is then focused on the numerical computation of the group velocity, the modal density and the total transmission loss.

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Mejdi, Abderrazak, Luca Alimonti i Bryce Gardner. "On homogenized ribbed-panel model for SEA analysis". INTER-NOISE and NOISE-CON Congress and Conference Proceedings 265, nr 2 (1.02.2023): 5292–303. http://dx.doi.org/10.3397/in_2022_0771.

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This paper presents an investigation into a recent model of homogenized rib-stiffened panels. An equivalent panel model is developed from the skin and the stiffeners of the panel. In this case a space-harmonic-based approach is used, and first-order shear deformation theory is employed to account for the wavefield's in-plane/out-of-plane coupling effect in the skin. The panel's stiffeners interact with the skin through internal forces and moments at the connections. A periodic FE mesh is then used to compute the wave dynamics and the results are used to develop the required terms to solve for vibro-acoustic results in Statistical Energy Analysis (SEA). This process is used to predict the vibro-acoustic response of an aircraft structure. The SEA results are compared with detailed FE models of the rib-stiffened aircraft structure.

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Mao, Qi Bo. "Experimental Study the Vibro-Acoustic Performance of a Double Glazed Window". Advanced Materials Research 503-504 (kwiecień 2012): 1129–32. http://dx.doi.org/10.4028/www.scientific.net/amr.503-504.1129.

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This paper presents an experimental investigation of the sound transmission and structural vibration characteristics of the double glazed window. The laboratory experiments were performed placing the window between reverberation chamber and anechoic chamber. The window was subject to diffuse field, approximate normal wave and oblique wave acoustic excitations. The sound transmission performances at far-field were measured. Furthermore, experimental modal analysis has been performed. The Least square complex exponential algorithm is used to extract the modal parameters, i.e. mode shapes, natural frequencies and modal damping ratio of the structure. The results also show that the highest sound transmission of this experimental double glazed window appears around the mass-air-mass resonance frequency.

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Alnutayfat, Abdullah, Sophia Hassiotis, Dong Liu i Alexander Sutin. "Sideband Peak Count in a Vibro-Acoustic Modulation Method for Crack Detection". Acoustics 4, nr 1 (24.01.2022): 74–86. http://dx.doi.org/10.3390/acoustics4010005.

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This paper presents a new method of signal processing for vibro-acoustic modulation (VAM) methods in order to detect damage accumulation in steel samples. Damage in the tested samples was produced by cycle loading, which, with a small amplitude, was used as a pump wave to modulate an ultrasonic probe wave. Multiple sideband peaks were observed, which were used to characterize the modulation effect. We propose the effectiveness sideband peak number (SPN) method as an indicator of any damage accumulation when the load cycle is applied. Moreover, after comparing the SPN with the previously used modulation index (MI), we concluded that, for some of the samples, the SPN provided better damage indication than the MI. The presented results can be explained by a simple model of bilinear crack nonlinearity. This model demonstrates that the amplitude dependences of the sideband components on the pump and the probe wave amplitudes are very different from the quadratic crack model that is usually used for MI test explanation.

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Klepka, Andrzej, Wieslaw Jerzy Staszewski, Dario di Maio, Fabrizio Scarpa, Kong Fah Tee i Tadeusz Uhl. "Sensor Location Analysis in Nonlinear Acoustics Used for Damage Detection in Composite Chiral Sandwich Panels". Advances in Science and Technology 83 (wrzesień 2012): 223–31. http://dx.doi.org/10.4028/www.scientific.net/ast.83.223.

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This paper demonstrates damage detection in a smart sandwich panel with integrated piezoceramic transducers. The panel is built from a chiral honeycomb and two composite skins. A low-profile, surface-bonded piezoceramic transducer is used for high-frequency ultrasonic excitation. Low-frequency excitation is performed using a piezoceramic stack actuator. Ultrasonic sensing is performed using laser vibrometry. Nonlinear acoustics is applied for damage detection. The study is focused on sensor location analysis with respect to vibro-acoustic wave modulations. The paper demonstrates that when structure is damaged, the high-frequency “weak” ultrasonic wave is modulated by the low-frequency “strong” vibration wave. As a result frequency sidebands can be observed around the main acoustic harmonic in the spectrum of the ultrasonic signal. However, intensity of modulation strongly depends on sensor location.

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Huang, Zhehao, i Jinzhao Liu. "A joint vibro-acoustic method for periodic track short-wave defect identification". Applied Acoustics 204 (marzec 2023): 109239. http://dx.doi.org/10.1016/j.apacoust.2023.109239.

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Droz, C., Z. Zergoune, R. Boukadia, O. Bareille i M. N. Ichchou. "Vibro-acoustic optimisation of sandwich panels using the wave/finite element method". Composite Structures 156 (listopad 2016): 108–14. http://dx.doi.org/10.1016/j.compstruct.2016.01.025.

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He, Xue-Song, Qi-Bai Huang i Wei-Cai Peng. "Wave based method for mid-frequency analysis of coupled vibro-acoustic problem". International Journal of Mechanics and Materials in Design 4, nr 1 (5.12.2007): 21–29. http://dx.doi.org/10.1007/s10999-007-9044-0.

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Klepka, Andrzej, Wieslaw Jerzy Staszewski, Kajetan Dziedziech i Francesco Aymerich. "Non-Linear Vibro-Acoustic Wave Modulations - Analysis of Different Types of Low-Frequency Excitation". Key Engineering Materials 569-570 (lipiec 2013): 924–31. http://dx.doi.org/10.4028/www.scientific.net/kem.569-570.924.

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Signal processing method based on wavelet transform used in non-linear acoustic test is presented in the paper. The method is applied for sidebands identification in response signal acquired during vibro-acoustic modulation test of impacted carbon fiber reinforced plate (CFRP). The plate was impacted with known energy using drop-weight testing machine. The modulation effect in investigated specimen results from the interaction of low and high frequency excitation with damage. The paper investigates different than mono-harmonic low-frequency excitation usually used in non-linear acoustics tests. Application of aperiodic low-frequency excitation signal allows to omit the modal test, where natural frequency of the structure are estimated. However, this requires the use of dedicated signal processing methods.

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Guillon, Corentin, Emmanuel Redon i Laurent Maxit. "Vibroacoustic simulations with non-homogeneous TBL excitations: Synthesis of wall pressure fields with the Continuously-varying Uncorrelated Wall Plane Waves approach". INTER-NOISE and NOISE-CON Congress and Conference Proceedings 265, nr 7 (1.02.2023): 544–51. http://dx.doi.org/10.3397/in_2022_0075.

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A numerical method is presented to predict the vibro-acoustic response of a vibrating structure excited by a spatially inhomogeneous turbulent boundary layer(TBL). It is based on the synthesis of different realizations of the random pressure fluctuations that can be introduced as loadings of a vibro-acoustic model (such as a finite element model). To generate the pressures of the non-homogeneous turbulent boundary layer, the Uncorrelated Wall Plane Wave(UWPW) approach used so far for homogeneous TBL is extended. On a first step, this extension is based on a decomposition of the excited surface into sub-areas and on the averaged TBL parameters for each sub-area. In a second step, it consists in taking into account the interaction between the sub-areas and a refinement of the sub-area decomposition. This leads to the Continuously-varying Uncorrelated Wall Plane Waves (C-UWPW) approach. The accuracy of the proposed approach is investigated on a panel with a varying thickness and excited by a growing TBL triggered at one edge of the plate. The interests of the proposed approach in terms of accuracy and computation time are discussed. Finally, an illustration of the proposed approach to predict the radiated noise from a blade immersed in a water flow is proposed.

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Wu, Yanan, Li Li i Yunfei Zhang. "Study on Sound Radiation Characteristics and Sound Insulation of Extruded Aluminium Plate". Journal of Physics: Conference Series 2174, nr 1 (1.01.2022): 012051. http://dx.doi.org/10.1088/1742-6596/2174/1/012051.

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Abstract The use of extruded aluminium plates in the subway car body can reduce the weight of the car body, but it will bring about the negative result of increased noise in the car. The extruded aluminium panels belong to rib-stiffened plate structure in which both local short wave deformation and whole long wave deformation coexist. Studying the vibro-acoustic characteristics of this structure helps to effectively control the noise in the car. In this paper, Acoustic model of extruded aluminium plate and equivalent plate were both built up based on the hybrid method of finite element and statistical energy analysis(FE-SEA) and the statistical energy method (SEA) respectively. According to the theory of statistical energy analysis(SEA), the equivalent modelling method of the aluminium extrusion was presented using a single plate This paper focuses on the sound radiation characteristics and sound insulation of extrude and equivalent structures. Results show that no matter what method is used, the calculation of the sound power and sound insulation of the two structures has the same trend. However, the results of the FE-SEA method can capture the natural frequency of the board and be more accurate reflect vibro-acoustic characteristics of extruded aluminium panels in the middle and low frequency. Equivalent plate can well predict the sound radiation characteristics and sound insulation in the mid and high frequency by using the SEA parameters of the aluminium extrusion.

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Pieczonka, Łukasz, Andrzej Klepka, Wieslaw Jerzy Staszewski, Tadeusz Uhl i Francesco Aymerich. "Analysis of Vibro-Acoustic Modulations in Nonlinear Acoustics Used for Impact Damage Detection - Numerical and Experimental Study". Key Engineering Materials 558 (czerwiec 2013): 341–48. http://dx.doi.org/10.4028/www.scientific.net/kem.558.341.

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The paper investigates experimentally the effect of low-frequency vibration on nonlinear vibro-acoustic wave modulations applied to the detection of Barely Visible Impact Damage (BVID) in a composite plate. Finite Element (FE) modeling was used in a pretest stage to identify different motion scenarios of delaminated surfaces and relate them to natural frequencies of the damaged plate. In particular the opening-closing and frictional sliding actions of the defected interfaces have been considered. Subsequently, the identified frequencies have been used for low frequency excitation in nonlinear acoustic experiments on a composite plate with impact damage.

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Ramezani, Majid G., Behnoush Golchinfar, Dimitri Donskoy, Sophia Hassiotis i Giri Venkiteela. "Steel Material Degradation Assessment Via Vibro-Acoustic Modulation Technique". Transportation Research Record: Journal of the Transportation Research Board 2673, nr 10 (27.05.2019): 579–85. http://dx.doi.org/10.1177/0361198119838271.

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The increasing probability of collapse in defective structures owing to aging is one of the major issues in transportation. Therefore, different methodologies that are capable of monitoring structural components have been used to identify defects and predict failure. Among these methods, the non-linear vibro-acoustic modulation (VAM) technique has been implemented for many years in a variety of industries, such as aerospace. This method utilizes the effect of nonlinear interactions between a high frequency ultrasonic wave (carrier signal) and a much lower frequency structural vibration (modulating signal). This interaction takes place at nonlinear interfaces (cracks, bolted connections, delaminations, etc.) manifesting itself in the spectrum as side-band components around the carrier frequency. In this study, the VAM method was investigated as a non-destructive evaluation (NDE) method for fracture critical members (FCMs) in steel bridges. The results of the experimental studies revealed that using the VAM technique on test specimens during the tension only fatigue tests would provide some useful information on the existence of micro-cracks and on failure prediction. The use of the VAM technique for center-notched rectangular test specimens of structural steel under low-amplitude fatigue loading at a frequency of 10 Hz is capable of predicting the failure at 70–80% of the fatigue lifetime of the specimen. Moreover, in this investigation utilizing fatigue cycling as a modulating signal was successfully substituted for the conventional utilization of resonance structural bending vibrations.

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Maess, Matthias K., i Lothar Gaul. "Simulation of Structural Deformations of Flexible Piping Systems by Acoustic Excitation". Journal of Pressure Vessel Technology 129, nr 3 (2.10.2006): 363–71. http://dx.doi.org/10.1115/1.2748819.

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Valve actuation and pump fluctuation in piping systems generate propagating sound waves in the fluid path which in turn can lead to undesired excitation of structural components. This vibro-acoustic problem is addressed by studying the propagation dynamics as well as the excitation mechanism. Fluid-structure interaction has a significant influence on both hydroacoustics and on structural deformation. Therefore, pipe models are generated in three dimensions by using finite elements in order to include higher-order deflection modes and fluid modes. The acoustic wave equation in the fluid is hereby fully coupled to the structural domain at the fluid-structure interface. These models are used for simulating transient response and for performing numerical modal analysis. Unfortunately, such 3D models are large and simulation runs turn out to be very time consuming. To overcome this limitation, reduced pipe models are needed for efficient simulations. The proposed model reduction is based on a series of modal transformations and modal truncations, where focus is placed on the treatment of the nonsymmetric system matrices due to the coupling. Afterwards, dominant modes are selected based on controllability and observability considerations. Furthermore, modal controllabilities are used to quantify the excitation of vibration modes by a white noise acoustic source at the pipe inlet. The excitation of structural elements connected to the piping system can therefore be predicted without performing transient simulations. Numerical results are presented for a piping system consisting of straight pipe segments, an elbow pipe, joints, and a target structure. This example illustrates the usefulness of the presented method for vibro-acoustic investigations of more complex piping systems.

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Gevorgyan, S. G., A. S. Khachunts, G. S. Gevorgyan, A. A. Tumanian i N. E. Tadevosyan. "Applicability of the single-layer flat-coil-oscillator technology-based vibration and vibro-acoustic sensors in medical and biological study of the cardiovascular system: Advantages and perspectives of the carotid pulse wave registration". Review of Scientific Instruments 93, nr 5 (1.05.2022): 054109. http://dx.doi.org/10.1063/5.0076197.

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The possibility and feasibility of using the single-layer flat-coil-oscillator (SFCO) technology-based vibration and vibro-acoustic sensors in diagnostic devices and biomedical studies of the cardiovascular system are discussed in this paper. Using an example of recording pulse waves of left carotid artery and their analysis, the information content of the data recorded by these sensors in a number of cases is shown—assessment of age-related changes in the stiffness of the vascular wall, assessment of the dynamics of systolic volume, reflecting myocardial contractility, and rhythm disturbance (extra-systole and arrhythmia). These sensors are shown to be promising in recording heart sounds due to their high sensitivity. The possibility of assessing the dynamics of relaxation of the cardiovascular system after exercise ( stress test) is shown. The advantages of using SFCO vibration and vibro-acoustic sensors are high sensitivity, ease of use, and no need to train specialists. These advantages open new perspectives for their implementation in mobile wearable “smart” devices for individual monitoring.

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Klepka, A., WJ Staszewski, RB Jenal, M. Szwedo, J. Iwaniec i T. Uhl. "Nonlinear acoustics for fatigue crack detection – experimental investigations of vibro-acoustic wave modulations". Structural Health Monitoring: An International Journal 11, nr 2 (25.07.2011): 197–211. http://dx.doi.org/10.1177/1475921711414236.

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Klepka, A., L. Pieczonka, W. J. Staszewski i F. Aymerich. "Impact damage detection in laminated composites by non-linear vibro-acoustic wave modulations". Composites Part B: Engineering 65 (październik 2014): 99–108. http://dx.doi.org/10.1016/j.compositesb.2013.11.003.

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32

Huang, Anmin, Minqing Wang, Daxiong Liao i Zhiwei Guo. "Study on vibro-acoustic characteristics of an adaptive piezoelectric locally resonant structure". Journal of Physics: Conference Series 2458, nr 1 (1.03.2023): 012018. http://dx.doi.org/10.1088/1742-6596/2458/1/012018.

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Abstract Adaptively reducing low-frequency broadband vibration and noise is a challenge in the engineering and needs to be resolved. A piezoelectric locally resonant structure with periodic piezoelectric units and shunt damping circuits of synthetic impedance was studied to provide an option to deal with the problem. The z-scores method was applied to identify the peak frequencies used in the setting of control parameters. The band-gap performance and vibro-acoustic response were analyzed based on the plane wave expansion method and finite element method, respectively. The results show that the considered locally resonant piezoelectric structure with the z-scores peak-detection method can adaptively suppress the vibration and acoustic radiation of the plate, providing an effective method to reduce vibration and noise in time-varying excitation situations.

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Broda, Dariusz, Krzysztof Mendrok, Vadim V. Silberschmidt, Lukasz Pieczonka i Wieslaw J. Staszewski. "The Study of Localized Crack-Induced Effects of Nonlinear Vibro-Acoustic Modulation". Materials 16, nr 4 (16.02.2023): 1653. http://dx.doi.org/10.3390/ma16041653.

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The nonlinear interaction of longitudinal vibration and ultrasound in beams with cracks is investigated. The central focus is on the localization effect of this interaction, i.e., the locally enhanced nonlinear vibro-acoustic modulation. Both numerical and experimental investigations are undertaken. The finite element (FE) method is used to investigate different crack models, including the bi-linear crack, open crack, and breathing crack. A parametric study is performed considering different crack depths, locations, and boundary conditions in a two-dimensional beam model. The study shows that observed nonlinearities (i.e., nonlinear crack–wave modulations) are particularly strong in the vicinity of the crack, allowing not only for crack localization but also for the separation of the crack-induced nonlinearity from other sources of nonlinearity.

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34

Ghavami, Siavash, Adriana Gregory, Jeremy Webb, Mahdi Bayat, Max Denis, Viksit Kumar, Todd Milbrand, A. Larson, Mostafa Fatemi i Azra Alizad. "Ultrasound Radiation Force for the Assessment of Bone Fracture Healing in Children: An In Vivo Pilot Study". Sensors 19, nr 4 (24.02.2019): 955. http://dx.doi.org/10.3390/s19040955.

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Vibrational characteristics of bone are directly dependent on its physical properties. In this study, a vibrational method for bone evaluation is introduced. We propose a new type of quantitative vibro-acoustic method based on the acoustic radiation force of ultrasound for bone characterization in persons with fracture. Using this method, we excited the clavicle or ulna by an ultrasound radiation force pulse which induces vibrations in the bone, resulting in an acoustic wave that is measured by a hydrophone placed on the skin. The acoustic signals were used for wave velocity estimation based on a cross-correlation technique. To further separate different vibration characteristics, we adopted a variational mode decomposition technique to decompose the received signal into an ensemble of band-limited intrinsic mode functions, allowing analysis of the acoustic signals by their constitutive components. This prospective study included 15 patients: 12 with clavicle fractures and three with ulna fractures. Contralateral intact bones were used as controls. Statistical analysis demonstrated that fractured bones can be differentiated from intact ones with a detection probability of 80%. Additionally, we introduce a “healing factor” to quantify the bone healing progress which successfully tracked the progress of healing in 80% of the clavicle fractures in the study.

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35

Droz, C., C. Zhou, M. N. Ichchou i J. P. Lainé. "A hybrid wave-mode formulation for the vibro-acoustic analysis of 2D periodic structures". Journal of Sound and Vibration 363 (luty 2016): 285–302. http://dx.doi.org/10.1016/j.jsv.2015.11.003.

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He, Xuesong, Qibai Huang i Caixia You. "A new sensitivity analysis scheme for coupled vibro-acoustic system using wave based method". Archive of Applied Mechanics 79, nr 2 (14.03.2008): 125–34. http://dx.doi.org/10.1007/s00419-008-0219-4.

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Broda, Dariusz, Andrzej Klepka, Wieslaw Jerzy Staszewski i Fabrizio Scarpa. "Nonlinear Acoustics in Non-Destructive Testing - From Theory to Experimental Application". Key Engineering Materials 588 (październik 2013): 192–201. http://dx.doi.org/10.4028/www.scientific.net/kem.588.192.

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A growing interest in non-destructive testing methods based on nonlinear acoustics have been observed for the last ten fifteen years. The majority of methods in this area take their origin from the observation that fatigue damaged materials often behave like mesoscopic nonlinear materials (e.g. rocks) in which nonlinear phenomena have been observed for years. The most important phenomena include: higher harmonics generation, vibro-acoustic wave modulations, amplitude dependent resonance frequency shift and slow dynamic effects. All these phenomena result mainly from elastic wave interactions with contact-type defects. There is enough experimental evidence in the literature showing that these nonlinear effects are much more distinct in damaged materials than in intact ones. Despite the fact that many experimental techniques - based on nonlinear acoustic phenomena - have been developed for the last ten years, the physical mechanism of elastic wave interaction with damage materials still not clear. The main reason is the variety of possible nonlinear mechanisms involved. This includes: nonlinear elasticity and dissipation, contact acoustic nonlinearity based on herztian and rough surfaces contact theories and other effects such us adhesion, friction and thermoelasticity. This paper provides a short summary of various theoretical developments and examples of applications to damage detection in different materials.

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38

Wang, Yuan, Jianrun Zhang, Xinzhou Zhang i Bo Wu. "Vibro-acoustic analysis of a trapezoidal cavity with a clamped flexible wall". Journal of Low Frequency Noise, Vibration and Active Control 37, nr 4 (11.06.2018): 801–15. http://dx.doi.org/10.1177/1461348418781870.

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The coupled model between trapezoidal cavity and its clamped flexible wall is developed using classical modal coupling theory. Based on the coupled model, the resonance frequencies of coupled system are obtained and compared with the corresponding uncoupled one. Meanwhile, the reason for the variation of resonance frequencies of coupled system modes is analyzed in detail. Then, the response of coupled system is investigated using the acoustic potential energy in the cavity and panel vibration kinetic energy when it is excited by an incident plane wave outside of the cavity. Coupling coefficient between trapezoidal cavity and its clamped flexible wall is proposed to assess the modal matching degree between them. It is shown that the coupling selection is not satisfied except in the axis direction which is parallel to the inclined wall. In addition, a rectangular cavity with a clamped flexible wall is also considered and compared with that of the trapezoidal one.

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39

Urbán, Daniel, N. B. Roozen, Vojtech Jandák, Marek Brothánek i Ondřej Jiříček. "On the Determination of Acoustic Properties of Membrane Type Structural Skin Elements by Means of Surface Displacements". Applied Sciences 11, nr 21 (4.11.2021): 10357. http://dx.doi.org/10.3390/app112110357.

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The article focuses on the determination of the acoustic properties (sound transmission loss, sound absorption and transmission coefficient under acoustic plane wave excitation) of membrane-type of specimens by means of a combination of incident plane wave sound pressure and membrane surface displacement information, measuring the sound pressure with a microphone and the membrane displacement by means of a laser Doppler vibrometer. An overview of known measurement methods and the theoretical background of the proposed so-called mobility-based method (MM) is presented. The proposed method was compared with the conventional methods for sound transmission loss and absorption measurement in the impedance tube, both numerically and experimentally. Finite element model (FEM) simulation results of two single layer membrane samples of different shape configurations were compared, amongst which six different variations of the backing wall termination. Four different approaches to determine the sound transmission loss and two methods to determine sound absorption properties of the membranes were compared. Subsequently, the proposed method was tested in a laboratory environment. The proposed MM method can be possibly used to measure the vibro-acoustic properties of building parts in situ.

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40

Du, Xiaofei, Dacheng Huang, Qidi Fu i Jianrun Zhang. "Effects of Acoustic Black Hole Parameters and Damping Layer on Sound Insulation Performance of ABH Circular Plate". Applied Sciences 9, nr 24 (9.12.2019): 5366. http://dx.doi.org/10.3390/app9245366.

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The acoustic black hole (ABH) can be utilized to achieve aggregation of flexural wave in structures with the feature that the thickness gradually reduced to zero with a power exponent no less than 2. The above characteristics could be applied in vibration reduction, noise attenuation or improving sound insulation. Previous literatures on vibration and acoustic characteristics of ABH structures mainly focus on the structural response under mechanical force excitation, while the transmission loss (TL) of circular plates embedded with two-dimensional ABHs investigated in this paper is a vibro-acoustic coupling procedure under excitation of diffuse sound field. Series of vibro-acoustic coupling finite element models (FEM) for TL analysis of ABH circular plates were established by automatic matched layer (AML) method in this paper and an experimental platform for measuring TLs of ABH circular plates and uniform plates was constructed. The accuracy of the FEM analysis was verified by experimental measurements. To systematically analyze the influence mechanism of parameters of the ABH on TLs of ABH circular plates, the effects of diameter, orientation, number, and truncation thickness of ABHs on TLs of ABH circular plates were further studied. The effect of the damping layer on TLs of circular plates embedded with 1 and 19 ABHs was also analyzed and it reveals that the influence of damping layer mainly concentrates on the first-order resonance frequency and damping-controlled region of the plate, and at some frequencies, the greater the damping layer thickness, the worse the sound insulation performance, despite that the modal damping loss factor has been increased in the whole frequency domain.

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41

Patel, Yatinkumar, Giedrius Janusas, Arvydas Palevicius i Andrius Vilkauskas. "Development of Nanoporous AAO Membrane for Nano Filtration Using the Acoustophoresis Method". Sensors 20, nr 14 (9.07.2020): 3833. http://dx.doi.org/10.3390/s20143833.

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A concept of a nanoporous anodic aluminum oxide (AAO) membrane as a vibro-active micro/nano-filter in a micro hydro mechanical system for the filtration, separation, and manipulation of bioparticles is reported in this paper. For the fabrication of a nanoporous AAO, a two-step mild anodization (MA) and hard anodization (HA) technique was used. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to analyze the surface morphology of nanoporous AAO. A nanoporous structure with a pore diameter in the range of 50–90 nm, an interpore distance of 110 nm, and an oxide layer thickness of 0.12 mm with 60.72% porosity was obtained. Fourier-transform infrared spectroscopy (FTIR) and energy-dispersive X-ray spectroscopy (EDS) were employed to evaluate AAO chemical properties. The obtained results showed that the AAO structure is of hexagonal symmetry and showed where Al2O3 is dominant. The hydrophobic properties of the nanoporous surface were characterized by water contact angle measurement. It was observed that the surface of the nanoporous AAO membrane is hydrophilic. Furthermore, to determine whether a nanomembrane could function as a vibro-active nano filter, a numerical simulation was performed using COMSOL Multiphysics 5.4 (COMSOL Inc, Stockholm, Sweden). Here, a membrane was excited at a frequency range of 0–100 kHz for surface acoustics wave (SAW) distribution on the surface of the nanoporous AAO using a PZT 5H cylinder (Piezo Hannas, Wuhan, China). The SAW, standing acoustic waves, and travelling acoustic waves of different wavelengths were excited to the fabricated AAO membrane and the results were compared with experimental ones, obtained from non-destructive testing method 3D scanning vibrometer (PSV-500-3D-HV, Polytec GmbH, Waldbronn, Germany) and holographic interferometry system (PRISM, Hy-Tech Forming Systems (USA), Phoenix, AZ, USA). Finally, a simulation of a single nanotube was performed to analyze the acoustic pressure distribution and time, needed to center nanoparticles in the nanotube.

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42

Van Genechten, Bert, Dirk Vandepitte i Wim Desmet. "A direct hybrid finite element – Wave based modelling technique for efficient coupled vibro-acoustic analysis". Computer Methods in Applied Mechanics and Engineering 200, nr 5-8 (styczeń 2011): 742–64. http://dx.doi.org/10.1016/j.cma.2010.09.017.

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Oliazadeh, Pouria, i Aref Afsharfard. "Analytical study of vibro-acoustic response of a human aorta subjected to an ultrasound wave". Applied Acoustics 175 (kwiecień 2021): 107849. http://dx.doi.org/10.1016/j.apacoust.2020.107849.

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Gascón-Pérez, Manuel. "Acoustic Influence on the Vibration of a Cylindrical Membrane Drum Filled with a Compressible Fluid". International Journal of Applied Mechanics 09, nr 05 (lipiec 2017): 1750072. http://dx.doi.org/10.1142/s1758825117500727.

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The study of the dynamic behavior of a membrane in contact with a fluid is interesting due to the numerous applications in technology. The vibro-acoustic behavior of a circular membrane in a cylindrical container or a membrane drum filled with a nonviscous fluid is analyzed. A boundary element method is used and the acoustic pressure over the boundary is calculated employing the Kirchhoff’s integral equation and that with the equation of motion of the membrane, the natural frequencies of vibration are obtained. Furthermore, the effect of the drum height, drum radius, membrane material density, tension parameter and fluid density on the frequencies are evaluated, as well as the variation of the fluid mass coefficient with the wave number. Validation of the method is made comparing the results with those obtained by other authors and theories.

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Szczepański, Grzegorz, Marlena Podlesna i Krzysztof Lada. "The study of the acoustical properties of a 3D printed noise barrier". INTER-NOISE and NOISE-CON Congress and Conference Proceedings 265, nr 3 (1.02.2023): 4904–10. http://dx.doi.org/10.3397/in_2022_0710.

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According to the data of the Statistic Poland, noise is the most common harmful factor in the work environment in Poland. In 2020, the number of persons exposed to noise was 181.7 thousand person. Reducing the noise hazard is a primary objective of vibro-acoustic research, and modern technology allows to achieve this goal in numerous ways. The most important and widespread technique used to reduce the risk of noise exposure of workers is to place noise absorbing or reflecting elements in the workplace. One of the less conventional methods used to produce such elements is the use of Fused Deposition Modelling. The opportunities that this method presents allow for manufacturing of noise barriers with advanced internal structures, which can reduce the noise transmission or manipulate the propagation of the sound wave. This article describes the study of acoustic properties of a noise barrier made using a 3D printer. The influence of various 3D printing settings on the obtained acoustic properties of the barrier was investigated. By measuring the acoustic pressure level and the particle velocity in three directions, the acoustic properties of the created barrier were determined.

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46

Jin, Ye Qing, Fu Zhen Pang, Dong Tang i Xiao Zhong Xie. "Sound Transmission through Lightweight Metallic Plate by Fourier Transform Method". Advanced Materials Research 676 (marzec 2013): 325–29. http://dx.doi.org/10.4028/www.scientific.net/amr.676.325.

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A theoretical model is developed to investigate sound transmission characteristics of an infinite lightweight plate line connected to equally spaced stiffeners and excited by an oblique plane wave. The reactive forces and moments at the line connections are obtained from the flexural and torsional motions of the stiffeners. The vibro-acoustic equation that describes the dynamic response of the structure is derived by employing the Fourier Transform method, which will be numerically solved by truncating the solution to converge. Numerical examples are presented to investigate the effects of the incidence angle, the stiffener spacing, the plate thickness, on the sound transmission characteristic of the system, and useful conclusions are drawn.

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Piana, Edoardo, Candida Petrogalli, Diego Paderno i Ulf Carlsson. "Application of the Wave Propagation Approach to Sandwich Structures: Vibro-Acoustic Properties of Aluminum Honeycomb Materials". Applied Sciences 8, nr 1 (1.01.2018): 45. http://dx.doi.org/10.3390/app8010045.

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48

Pan, Chenge, Xianbo Sun i Yahui Zhang. "Vibro-acoustic analysis of submerged ring-stiffened cylindrical shells based on a symplectic wave-based method". Thin-Walled Structures 150 (maj 2020): 106698. http://dx.doi.org/10.1016/j.tws.2020.106698.

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49

Pluymers, B., W. Desmet, D. Vandepitte i P. Sas. "Application of an efficient wave-based prediction technique for the analysis of vibro-acoustic radiation problems". Journal of Computational and Applied Mathematics 168, nr 1-2 (lipiec 2004): 353–64. http://dx.doi.org/10.1016/j.cam.2003.05.020.

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Jia, Di, Fu Zhen Pang, Xu Chao Yin i Ye Xi. "Study on the Vibro-Acoustic Characteristics of a Vibration Isolation Mass Structure with Composite Braces". Applied Mechanics and Materials 117-119 (październik 2011): 85–88. http://dx.doi.org/10.4028/www.scientific.net/amm.117-119.85.

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In this paper a vibration isolation mass structure with composite braces is proposed to reduce noise and vibration transmission through the hull and internals of a double cylindrical shell. Influence of the various complicating effects such as vibration isolation mass’s cross section size or the layout location on the vibration isolation performance of composite braces structure are discussed. Besides, we also provide a composite structure form with high transmission loss due to the theory of vibration insulation of isolation mass and noise reduction of damping material. Study shows that composite braces structure combined the appropriate vibration isolation mass with viscoelastic material can effectively decrease the hull vibration and sound radiation in the mid-high frequency domain, which can significantly attenuate transmission of the plate flexural wave.

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