Article
Chemistry, Analytical
Juan Carlos Pineda Allen, Ching Tai Ng
Summary: This study investigates the application of nonlinear guided-wave mixing for integrity monitoring of bolted joints in plates. Combinational harmonics were found to be highly correlated to the applied torque level in the joint, and remain robust for different numbers of cycles in detecting bolt loosening. The findings provide physical insight into the phenomena of nonlinear Lamb wave mixing for evaluating applied torque in bolted joints.
Article
Engineering, Electrical & Electronic
Xiaowei Jiang, Keming Ma, Shaowei Lu, Lu Zhang, Zhi Wang, Yilin Guo, Xiaoqiang Wang, Ziping Zhao, Xiaoqiang Qu, Yao Lu
Summary: This study presents a conductive MXene/FPC based pressure sensor that significantly improves the monitoring range and stability, overcoming the limitations of traditional MXene sensors. Experimental results demonstrate the effectiveness and reliability of using MXene sensors for detecting bolt loosening in real-time under various conditions.
SENSORS AND ACTUATORS A-PHYSICAL
(2021)
Article
Acoustics
Ahmed Sallam, Shima Shahab
Summary: In this study, an adaptive numerical algorithm for computationally efficient nonlinear acoustic holography is proposed. The algorithm adjusts its discretization parameters based on the harmonic content of the acoustic signal, enabling efficient local resolution of higher harmonics in areas of high nonlinearity while avoiding unnecessary resolution elsewhere. The algorithm also adapts to the signal's nonlinearity level, eliminating the need for prior reference simulations or information about the spatial distribution of the harmonic content.
IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL
(2023)
Article
Mechanics
Xi Liu, Biao Wang, Nao-Aki Noda, Yoshikazu Sano, Yuto Inui, Kosuke Tateishi, Yasushi Takase
Summary: This study conducted experiments and used three-dimensional FEM to analyze the tightening and untightening processes of nuts, proposing a new formula for untightening pitch difference nuts and clarifying their ability to resist loosening.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2023)
Article
Mechanics
Mads Peter Sorensen, Peter Leth Christiansen
Summary: A computational investigation was conducted on the propagation of weakly nonlinear model of acoustical plane waves in a cylindrical tube. Oscillating shock waves were observed in the weakly nonlinear model when the driving frequency was slightly higher than the first resonance frequency of the simple wave equation. Two counter propagating shock waves were observed in the tube when the driving frequency was slightly above the second harmonic frequency of the simple linear wave equation. The article also includes a Hamiltonian energy analysis, demonstrating the balance between the energy input and the dissipation of the wave dynamics.
Article
Optics
Saeed Ghavami Sabouri
Summary: The study investigates the generation of second harmonic in vortex beams in a nonlinear crystal with an inhomogeneous refractive index by manipulating the temperature gradient along the crystal thickness. The OAM spectrum of the vortex beams can be changed by inducing a transverse phase mismatch, resulting in the generation of new OAM components. This method offers advantages of longer interaction length and higher efficiency compared to the nonlinear Bragg diffraction method.
Article
Construction & Building Technology
Rusong Miao, Ruili Shen, Fenglin Tang, Wei Chen, Ming Que
Summary: The study investigates the nonlinear interaction effect during clamp bolt tightening through both field experiment and finite element modeling. It is found that clamps with longer lengths and more rows of bolts tend to exhibit higher degrees of nonlinear interaction effect. Additionally, the side-to-centre bolt tightening sequence is more efficient compared to the centre-to-side sequence.
JOURNAL OF CONSTRUCTIONAL STEEL RESEARCH
(2021)
Article
Physics, Multidisciplinary
Jonas Helboe Joergensen, Wei Qiu, Henrik Bruus
Summary: This study investigates acoustic streaming at high acoustic energy densities in a microfluidic channel. The results obtained from theoretical, numerical, and experimental methods demonstrate that frictional heating can significantly alter the streaming pattern at energy densities above 400 J/m3. The study shows that with increasing energy density at a fixed frequency, the traditional boundary-driven four streaming rolls transition into two larger streaming rolls.
PHYSICAL REVIEW LETTERS
(2023)
Article
Engineering, Mechanical
Xiaoshu Qin, Chang Peng, Gaozheng Zhao, Zengye Ju, Shanshan Lv, Mingshun Jiang, Qingmei Sui, Lei Jia
Summary: This study develops a full life-cycle monitoring approach for bolt loosening using a modified VAM method and nonlinear indexes, achieving earlier warning in the thread loosening stage. The results demonstrate the sensitivity of nonlinear indexes to predict bolt early looseness before the bolt head and interconnecting component loosening, contributing to the reliability of VAM-based bolt early loosening monitoring.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Mechanics
Varun Kumar Rajendran, Sujith Jayakumar, Mohammed Azharudeen, Karthick Subramani
Summary: In this study, a theory of nonlinear acoustics for inhomogeneous fluids is derived from first principles. This theory explains the phenomena of streaming suppression and acoustic relocation and predicts the relocation of higher impedance fluids to pressure nodes of standing waves.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Computer Science, Interdisciplinary Applications
Nuno M. R. Monteiro, Tiago C. A. Oliveira
Summary: This paper introduces a software toolkit called OMesh2KRAKEN, which uses OceanMesh2D to generate unstructured meshes for KRAKEN based on realistic environmental data, to assist in implementing underwater acoustic modeling studies from deep waters to nearshore regions.
ADVANCES IN ENGINEERING SOFTWARE
(2023)
Article
Nanoscience & Nanotechnology
Carolina Espinoza, Vicente Salinas, Makarena Osorio, Edgar Pio, Claudio Aguilar, Fernando Lund, Nicolas Mujica
Summary: Knowledge of the state of plastic deformation in metallic structures is crucial for failure prevention. Non-destructive acoustic tests based on first order elastic constants have limitations when plastic deformations are heterogeneous or have small variations in elastic constants. Digital image correlation techniques combined with finite element modeling provide information about plastic deformation in the sample interior. This study demonstrates that the nonlinear Second Harmonic Generation method (SHG) can detect von Mises stress zones and plastic strain in aluminum pieces, indicating sensitivity to dislocation density. Experimental results align with Finite Element Method (FEM) modeling and are supported by X-ray Diffraction measurements (XRD).
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Acoustics
Hui Li, Haiyu Lv, Hai Sun, Zhaoye Qin, Jian Xiong, Qingkai Han, Jinguo Liu, Xiangping Wang
Summary: This paper investigates the nonlinear vibrations of fiber-reinforced composite cylindrical shells with bolted joint boundary conditions, considering the nonlinear amplitude-dependent material property of FRCs and partial bolt loosening conditions. The study uses theoretical modeling and experimental validation to analyze the effects of bolt loosening degree and number on natural frequencies, damping ratios, and resonant response amplitudes of FRCCS structures. The results show that increased bolt loosening leads to decreased natural frequencies, increased damping ratios, and resonant response amplitudes due to the coupling effect of decreased boundary stiffness and increased boundary damping.
JOURNAL OF SOUND AND VIBRATION
(2021)
Article
Optics
Junjun Ma, Fei Xie, Weijin Chen, Jiaxin Chen, Wei Wu, Wei Liu, Yuntian Chen, Wei Cai, Mengxin Ren, Jingjun Xu
Summary: LN metasurfaces with controllable SHG properties have been experimentally demonstrated, showing distinct enhancements for the SHG efficiency at Mie resonances. By changing geometric parameters and resonances of metasurfaces, authors manage to selectively boost the SHG efficiency at different wavelengths, paving the way for developing novel compact nonlinear light sources with high flexibility for applications like biosensing and optical communications.
LASER & PHOTONICS REVIEWS
(2021)
Article
Construction & Building Technology
Jianxi Qiu, Saqlain Abbas, Yanping Zhu, Zulkarnain Abbas
Summary: This study proposes an integrated method for online monitoring of bolted state, especially for small size and compact measured components. The method analyzes the signal characteristics in the frequency domain to find the frequency components associated with bolt looseness. The effectiveness of the method is experimentally verified, and damage characteristics can be obtained without a reference signal.
STRUCTURAL CONTROL & HEALTH MONITORING
(2022)
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)