Article
Engineering, Multidisciplinary
Hamad Alnuaimi, Umar Amjad, Pietro Russo, Valentina Lopresto, Tribikram Kundu
Summary: A holistic technique combining linear and nonlinear ultrasonic techniques was proposed for monitoring damage in composite plates. By using multiple sets of specimens made of different materials, it was found that linear and nonlinear ultrasonic parameters exhibit different monitoring effects in various stages of damage progression.
STRUCTURAL HEALTH MONITORING-AN INTERNATIONAL JOURNAL
(2021)
Article
Materials Science, Multidisciplinary
Jeongnam Kim, Junpil Park, Bo Zhu, Younho Cho
Summary: The study introduces a non-destructive method for quantitatively assessing fatigue damage of materials with linear elastic properties using nonlinear ultrasonic techniques. A numerical method based on the semi-analytical finite element (SAFE) technique was used to obtain phase-matching modes of specimens. It was confirmed through experiments that nonlinearity tends to increase with levels of fatigue in shot peening and certain fatigue samples.
Article
Mathematics, Applied
Ravinder Poonia, Sunita Deswal, Kapil Kumar Kalkal
Summary: The objective of this research is to investigate the propagation of time harmonic plane waves in a rotating, nonlocal, transversely isotropic thermoelastic half-space with void pores. It has been observed that four coupled plane waves travel in such a medium at distinct speeds. The amplitude and energy ratios for the reflected waves are presented using appropriate boundary conditions. Numerical computations are performed using MATLAB software to study the effects of material anisotropy, nonlocality, void, and rotation parameters on the amplitude ratios. The results are displayed and explained through graphs, showing that the phase velocities of plane waves in transversely isotropic medium depend on the incident angle and energy conservation law is justified during the reflection phenomena.
ZAMM-ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK
(2023)
Review
Mechanics
Hongjuan Yang, Lei Yang, Zhengyan Yang, Yinan Shan, Haosen Gu, Jitong Ma, Xu Zeng, Tong Tian, Shuyi Ma, Zhanjun Wu
Summary: This study provides a comprehensive review of ultrasonic detection methods for damage diagnosis and assessment of advanced composite materials. It introduces typical damage types and their effects on composite materials, reviews ultrasonic measurement methods for determining composite material parameters, discusses acoustic models, detection techniques, and imaging methods based on ultrasonic bulk wave or guided wave detection technologies, and reviews damage diagnosis of composite materials, criteria for damage assessment, and analytical methods for predicting the remaining service life of damaged composites. Insights into the application prospects of advanced composite materials are also provided.
COMPOSITE STRUCTURES
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Jingfei Liu, Jurjen Leer, Salavat R. Aglayomov, Stanislav Y. Emelianov
Summary: This study proposes an ultrasonic Scholte-wave-based approach for imaging the elasticity of superficial tissue. By introducing a liquid layer between the ultrasound imaging transducer and the tissue-mimicking phantom, Scholte waves can be generated to image the elasticity of superficial tissue. Furthermore, by combining the proposed Scholte wave technique and the conventional shear wave technique, a comprehensive elasticity imaging of tissue from superficial to deep regions can be achieved.
Article
Physics, Applied
Peizheng Cao, Wenzhan Ou, Yingnan Su, Yuhang Yin, Erqian Dong, Zhongchang Song, Jiafang Li, Yu Zhang
Summary: In this study, an acoustic switch based on a spiral kirigami metasurface is designed and its performance is evaluated experimentally. The kirigami structure can control the sound propagation range, providing an alternative design strategy for acoustic metasurfaces.
PHYSICAL REVIEW APPLIED
(2022)
Article
Geochemistry & Geophysics
Andrey V. Lebedev
Summary: Acoustic logging is an important experimental technique widely used in exploration geophysics, prone to errors due to microscopic heterogeneity of rocks outside the borehole. Approximate descriptions can be adequate, leading to faster data processing and time savings.
Article
Acoustics
Xiukun Li, Yushuang Wu, Ge Yu, Yifei Zou
Summary: The resonance characteristics of elastic acoustic scattering are important for buried target detection and identification. By using COMSOL models, the influence of a burial layer on Rayleigh wave and Whispering-Gallery wave are analyzed. The method of isolation and identification of resonance (MIIR) is used to obtain elastic resonances in free-field and buried conditions.
Article
Acoustics
Beomseok Cha, Song Ha Lee, Syed Atif Iqrar, Hee-Gyeong Yi, Jangho Kim, Jinsoo Park
Summary: In this study, a vertical-type ultrasonic SAW-based microfluidic mixer was proposed for rapid flow mixing with improved efficiency and controllability. Computational fluid dynamics simulations and experimental investigations were conducted to elucidate the acousto-hydrodynamic phenomenon of the vertical-type SAW-induced ASF. The SAW-induced vortices acted as a hydrodynamic barrier for controlled flow mixing, and proof-of-concept application demonstrated rapid red blood cell lysis with high efficiency based on the physical interactions with the SAW-induced acoustic vortical flows.
ULTRASONICS SONOCHEMISTRY
(2023)
Article
Acoustics
Zuzana Dvorakova, Serge Dos Santos, Vaclav Kus, Zdenek Prevorovsky
Summary: This paper discusses the use of the time reversal approach and phi-divergences for signal classification in biomedical applications. The time reversal approach combined with nonlinear elastic wave spectroscopy is used to extract the nonlinear signature of air bubbles and ultrasound contrast agents. Signal classification is performed using the fuzzy classification method and the divergence decision tree algorithm based on specific phi-divergence spectral measures. The results show that different types of nonlinearities can be identified and the positions of scattered sources can be distinguished using phi-divergence methods.
JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA
(2023)
Article
Acoustics
Mushtaq Ali, Jinsoo Park
Summary: In droplet-based microfluidic platforms, there is increasing demand for precise separation of microscale droplets of different chemical composition. Most existing techniques focus on separating droplets of the same kind, while there is less effort on separating uniform-sized droplets of different chemical composition. This study proposes an acoustofluidic method using ultrasonic surface acoustic wave (SAW)-induced acoustic radiation force (ARF) to simultaneously separate uniform-sized droplets of different acoustic impedance. The experimental results show that the proposed method provides a label-free and detection-free approach for on-chip, precise separation of multiple kinds of droplets in microfluidic applications.
ULTRASONICS SONOCHEMISTRY
(2023)
Article
Chemistry, Physical
Evgeny V. Glushkov, Natalia V. Glushkova, Olga A. Ermolenko, Alexey M. Tatarinov
Summary: Tubular bones are complex structures composed of different tissue layers, and ultrasound diagnostics can be used to detect bone diseases through guided wave excitation and registration. However, the interior of the diseased area is shielded by upper layers, making it difficult to extract relevant information from surface signals. To address this issue, the study utilizes the Green's matrix-based approach and methods developed for industrial composite monitoring. By analyzing computer models and experimental measurements, the feasibility of using different wave characteristics to detect diagnostic signs of developing osteoporosis is evaluated. The results show that the improved matrix pencil method combined with objective functions based on the Green's matrix allows for effective monitoring of changes in the deeper layers' elastic moduli, and resonance response frequencies show sensitivity and monotonic dependence on the degradation of elastic properties, making them a promising indicator for osteoporosis diagnostics.
Article
Mathematics
Jie Xu
Summary: We present an iterative method to prove the existence and uniqueness of complex-valued nonlinear elliptic PDEs with specific boundary conditions on precompact domains and smooth, compact Riemannian manifolds. The method also provides a solution for an integral version of these PDEs using parametrix methods.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2023)
Article
Mechanics
M. P. Arunkumar, Vinod Bhagat, Qian Geng, Yueming Li, Jeyaraj Pitchaimani
Summary: This paper provides an exact solution for the vibro-acoustic response of Magneto-electro-elastic (MEE) composite plate and sandwich panels with MEE facings. It develops the governing equation of motion using Hamilton's principle with consideration of the third-order shear deformation theory. The analysis includes the influences of electric and magnetic potential on the vibro-acoustic response of various types of truss core and honeycomb core sandwich panels.
COMPOSITE STRUCTURES
(2022)
Article
Acoustics
Robert Malkin, Brian Kappus, Benjamin Long, Adam Price
Summary: Air-coupled phased arrays are of growing interest for their applications in acoustic levitation and mid-air haptics. This study investigates the non-linear propagation effects in high amplitude focused fields, such as the generation of harmonic frequencies and acoustic saturation. Experimental work is conducted to analyze non-linearities at different focusing distances and driving amplitudes. The results show that saturation losses can be significant and suggest metrics to identify and quantify non-linearities in air-coupled arrays.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Instruments & Instrumentation
Christos Andreades, Michele Meo, Francesco Ciampa
SMART MATERIALS AND STRUCTURES
(2020)
Article
Engineering, Multidisciplinary
Salvatore Boccardi, Gian Piero Malfense Fierro, Michele Meo
Summary: Structural health monitoring is crucial for assessing defects in material components. A sparse array of surface-bonded ultrasonic transducers can accurately locate and image damage, improving imaging accuracy and damage localization.
STRUCTURAL HEALTH MONITORING-AN INTERNATIONAL JOURNAL
(2021)
Article
Chemistry, Analytical
Marco Boccaccio, Pasquale Rachiglia, Gian Piero Malfense Fierro, Giovanni Pio Pucillo, Michele Meo
Summary: This study presents a design of a holey-structured metamaterial lens to improve acousto-ultrasonic imaging using air-coupled transducers, leading to enhanced sensitivity and resolution in damage imaging.
Article
Chemistry, Analytical
Frank Mevissen, Michele Meo
Summary: Nonlinear ultrasound crack detection methods, utilizing multi-frequency wave excitation and a new concept of nonlinearity parameter grouping, have been developed to better identify early damages in materials without calculating dispersion curves. Experimental validation on metal plates and turbine blades has shown that the use of multi-frequency excitation offers advantages in detecting cracks.
Article
Chemistry, Physical
Michele Meo, Francesco Rizzo, Mark Portus, Fulvio Pinto
Summary: Composite laminated materials are widely used in advanced applications due to their high tailorability of mechanical performance and low weight, but are prone to damage from out-of-plane loading. Functionally Graded Pitch (FGP) laminated composites, inspired by biological structures, have been designed to improve impact resistance, replicating the gradual pitch rotation found in natural structures.
Article
Materials Science, Composites
Francesco Flora, Fulvio Pinto, Michele Meo
Summary: This study focuses on the design of a new high-performance carbon FRP core for sandwich structures. The innovative core, manufactured using corrugated laminates, demonstrates enhanced energy absorption and compressive properties. Experimental evaluation shows significant improvements in specific properties compared to traditional aluminum honeycomb cores.
JOURNAL OF COMPOSITE MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Mario Rapisarda, Frank Marken, Michele Meo
Summary: An optimized gel derived from graphene oxide and starch acts as a hybrid binder for supercapacitors, delivering good rate performance and stability over 17,000 cycles.
COMMUNICATIONS CHEMISTRY
(2021)
Article
Engineering, Multidisciplinary
Francesco Flora, Francesco Rizzo, Fulvio Pinto, Michele Meo
Summary: The mechanical properties of composite laminates are directly affected by the level of porosity, highlighting the importance of adequate air debulking during manufacturing. The use of ultrasonic waves can enhance this step, leading to reductions in manufacturing time and improvements in interlaminar shear strength. A proposed model analytically describes the influence of ultrasonic stimulation on air flux and provides guidelines for optimizing process parameters. Experimental tests validate the efficiency of the ultrasonic consolidation (UC) process, showing significant reductions in voids and improvements in mechanical properties.
COMPOSITES PART B-ENGINEERING
(2022)
Article
Instruments & Instrumentation
Stefano Cuomo, Tim Baetzel, Niels Modler, Andreas Hornig, Michele Meo
Summary: Nowadays, components made of unidirectional composite materials are widely used in various engineering fields. However, the low out-of-plane properties of these materials make them susceptible to impulsive loads, such as impact events. Therefore, it is crucial to continuously assess the condition of structures and determine if damage has occurred. This study proposes a baseline-free methodology for determining the coordinates of high-velocity impacts on complex structures and evaluates the occurrence of damage during the impact. Experimental tests on carbon fibre reinforced polymers with embedded sensors demonstrate the effectiveness and reliability of the proposed method in accurately estimating impact localization and evaluating structural integrity.
SMART MATERIALS AND STRUCTURES
(2022)
Article
Nanoscience & Nanotechnology
Mario Rapisarda, Michele Meo
Summary: Graphene-based aerogels with chemical modifications show promising properties for automotive and aerospace industries, including high elastic resilience, low thermal conductivity, and high sound absorption.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Engineering, Mechanical
Stefano Cuomo, Marco Boccaccio, Michele Meo
Summary: This study proposes a novel baseline-free method for real-time structural damage diagnosis during low-and high-velocity impact by decomposing the propagating modes caused by impact events. The high-frequency and medium-low frequency components are separated using Hilbert-Huang Transform (HHT) to obtain amplitude and phase of two propagation modes. The Energy Ratio Xi, defined as the ratio between maximum instant energy of the extensional mode and flexural mode, is proposed as an indicator of damage probability. Experimental results on aluminium and CFRP samples demonstrate the effectiveness of the proposed method in discerning elastic and damaging impacts.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Engineering, Multidisciplinary
Marco Boccaccio, Gian Piero Malfense Fierro, Fabrizo Bucciarelli, Michele Meo
Summary: The proposed concept of acousto-ultrasound metamaterial-based structures aims to achieve high multi-tonal sound absorption and improve the performance of air-coupled nonlinear acoustic/ultrasound imaging. Experimental results show that these structures can achieve high absorption peaks at the fundamental frequency and odd harmonics, while amplifying the sound of even harmonics. The correlation between predicted model and experimental results indicates the promising potential of sub-wavelength metamaterials for controlling sound absorption and enhancing the accuracy of nonlinear ultrasound imaging applications.
ENGINEERING RESEARCH EXPRESS
(2021)
Article
Energy & Fuels
Gian Piero Malfense Fierro, Michele Meo
Summary: This study evaluated various nonlinear ultrasound methods for in situ structural health monitoring of a four-bolt structure on large-scale wind turbines. A frequency selection process based on modal response was suggested to determine specific bolt frequencies, showing an increase in nonlinearities as bolts loosened. Specific pre-identified frequencies can track the loosened status of individual bolts.
Article
Engineering, Aerospace
Frank Mevissen, Michele Meo
Article
Nanoscience & Nanotechnology
Mario Rapisarda, Michele Meo
Summary: This study presents the chemical modification approaches of graphene oxide and polyvinyl alcohol aerogels to achieve mechanically balanced and robust cellular structures. The modified aerogels exhibit high elastic resilience, low thermal conductivity, and high sound absorption while maintaining low density. Chemical reduced aerogels also demonstrate piezoresistive behavior with minimal impact on other properties.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Mechanics
E. Mubai, D. P. Mason
Summary: The two-dimensional turbulent thermal classical far wake is investigated in this study. The turbulence is described using the Boussinesq hypothesis for Reynolds stresses and Prandtl's mixing length model for eddy viscosity and eddy thermal conductivity. Two conservation laws are derived for the thermal boundary layer equations using the multiplier method, and two conserved quantities are obtained from the conserved vectors and boundary conditions. Lie point symmetry associated with the momentum and thermal conserved vectors is derived, showing that the momentum and thermal mixing lengths are proportional. An invariant solution is obtained numerically using a shooting method, and analytically when v = 0, kappa = 0.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2024)
Article
Mechanics
Daniel J. Arrigo, Travis C. Chism
Summary: This paper investigates the governing equations for plane stress deformations of isotropic incompressible hyperelastic materials. The authors previously discovered a linearization method for the plane strain case of the Varga material, and in this paper, they further demonstrate that the governing equations for the plane stress case can also be linearized.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2024)
Article
Mechanics
A. P. Chugainova, R. R. Polekhina
Summary: This article numerically investigates the conditions for the decay of a nonlinear wave into a system of waves traveling at different velocities in a viscoelastic weakly anisotropic medium. Solutions of a hyperbolic system of equations are studied in the region of nonuniqueness of parameters, where a solution to the Riemann problem can be constructed with both a single wave and a system of waves corresponding to the same initial data.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2024)
Article
Mechanics
Yu. N. Grigoriev, E. I. Kaptsov, S. V. Meleshko
Summary: This paper studies the mathematical properties of gasdynamics equations with thermochemical nonequilibrium and provides solutions for two different models. The results show that the solutions to the modified system of equations are physically consistent and can describe the effects of thermochemical nonequilibrium.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2024)
Article
Mechanics
Y. Hao, X. Y. Guo, Y. B. Fu
Summary: This paper investigates the nonlinear stochastic dynamic response of a three-degree-of-freedom(3-DOF) airfoil with high substructural nonlinearity under vertical turbulent disturbances. The effects of parameters such as the incoming velocity, turbulence scale and intensity on the stochastic dynamics behavior of the system are clarified.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2024)
Article
Mechanics
T. Flament, J. -F. Deu, A. Placzek, M. Balmaseda, D. -M. Tran
Summary: This paper focuses on the numerical computation of vibrations in geometrically nonlinear structures induced by aeroelastic coupling with fluid flow using reduced order models (ROM). The proposed ROM formulation utilizes projection on a basis of reduced dimension enhanced with dual modes, allowing for the accurate capture of dynamic characteristics and adaptation to unsteady aerodynamic loads. The limitations of the classical Implicit Condensation method are highlighted, while the ROM proposed overcomes these limitations and accurately captures the dynamics.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2024)
Article
Mechanics
Sidhartha Sankar Roy, Kishore Chandra Biswal
Summary: This study investigates the non-linear slosh dynamics of a sloped wall tank with a bottom-mounted object under seismic excitation. The potential flow theory is used to model the liquid domain using a mixed Eulerian-Lagrangian method. The study successfully quantifies the non-linear seismic response of the tank and the influence of the internal object on the hydrodynamic behavior. A parametric investigation is conducted by altering the object's height. Comparison with linear analysis justifies the necessity of non-linear analysis. The developed non-linear finite element model is found to be more effective and can be used in designing structure-coupled sloped wall TLDs.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2024)
Article
Mechanics
Kapil Dev, Om P. Suthar
Summary: This study presents stability analyses of thermosolutal convection in a Newtonian fluid-saturated Darcy porous layer under non-uniform inclined heating, considering the presence of the Soret effect. The results reveal the destabilizing effect of the solutal Darcy-Rayleigh number and Lewis number on the system's stability, while the Soret parameter has a non-monotonic effect depending on the horizontal Rayleigh number.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2024)
Article
Mechanics
Sandhya Maurya, Dia Zeidan, Manoj Pandey
Summary: This paper investigates a two-phase mass flow model governed by gravity, which involves solid particles and a viscous fluid. By utilizing the Lie symmetries admitted by the system, similarity solutions for the (2+1)-dimensional two-phase mass flow model are obtained. Through analytical solutions and numerical analysis, the physical behaviors of the resulting systems are successfully analyzed.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2024)
Article
Mechanics
Longfei Tan, Wei Zhang, Zixun Wang, Bowen Hou, Wei Sun
Summary: This study investigates the factors influencing the stiffness variation characteristics of a bolted joint during service, including macro deviation, micro-topography, and hysteresis characteristics. Through experiments and finite element modeling analysis, it is found that macro deviations and micro-topography on the bearing surface can cause irregular dynamic changes in the stiffness of the bolted joint, significantly affecting the dynamic/static response of the entire structure.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2024)
Article
Mechanics
Yu Xiao, Ze-Qi Lu, Nan Wu
Summary: This study investigates the characteristics of a magnet-engaged nonlinear piezoelectric energy generator stimulated by friction-induced vibration (FIV) in two distinct design configurations (in parallel and in-series). The results indicate that factors such as decay factor, dynamic friction coefficient, static friction coefficient, and normal force have an effect on the stability of the system and the generation of FIV. The in-parallel systems exhibit a higher charging power within the same operating range, while the in-series systems are more likely to excite FIV with a wider operating range.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2024)
