A5091465799- Ultrasonics and Acoustic Wave Propagation
- Non-Destructive Testing Techniques
- Geophysical Methods and Applications
- Structural Health Monitoring Techniques
- Shape Memory Alloy Transformations
- Acoustic Wave Resonator Technologies
- Piezoelectric Actuators and Control
- Microwave Imaging and Scattering Analysis
- Geotechnical and Geomechanical Engineering
- Structural Analysis and Optimization
- Ultrasound Imaging and Elastography
- Force Microscopy Techniques and Applications
- Fluid Dynamics Simulations and Interactions
- Thermography and Photoacoustic Techniques
- Ship Hydrodynamics and Maneuverability
East China University of Science and Technology
2017-2023
Tianjin University
2014
University of Macau
2013
Online and offline monitoring of composite bolted joints under tensile load were investigated using piezoelectric transducers. The relationships between Lamb wave signals, pre-tightening force, the applied load, as well failure modes investigated. Results indicated that S0/A0 amplitudes decrease with increasing load. Relationships damage features mode built based on finite element (FE) simulation experimental results. possibility application wave-based structure health in joint-like...
Localization of fatigue cracks imposes immense significance to ensure the health engineering structures and prevent further catastrophic accidents. The nonlinear ultrasonic waves, especially Lamb have been increasingly studied employed for identifying micro-damages that are usually invisible traditional linear waves. However, it remains a challenge locate using waves owing enormous difficulties in decoding location information from acoustic nonlinearity. Motivated by this, this work presents...
Abstract. This paper investigates the existing stiffness equations for corner-filleted flexure hinges. Three empirical hinges (each fillet radius, r, equals to 0.1 l; l, length of a hinge) are formulated based on finite element analysis results purpose overcoming these investigated limitations. comparisons made with compliance/stiffness and (FEA) indicate that proposed enlarge range rate thickness (t, minimum (l), t/l (0.02 ≤ 1) ensure accuracy each equation under large...
Most imaging methods based on ultrasonic Lamb waves in structural health monitoring requires reference signals, recorded the intact state. This paper focuses a novel baseline-free method for damage localization using hyperbolic algorithm. employs special array with relatively small number of transducers and only one branch hyperbola. The symmetrical was arranged plate structures to eliminate direct waves. time difference between received signals at sensors obtained from damage-scattered...
Nonlinear Lamb waves have attracted increasing attention for detecting and identifying microstructural changes in structural health monitoring. However, most identification methods that determine the damage locations based on intersections of elliptical loci will inevitably cause positioning errors due to change group velocity before after interaction with damage. In this work, a method focusing rings was proposed localization imaging micro-cracks three-dimensional structure using nonlinear...
AbstractThe aim of this study is to describe the hysteretic nonlinear characteristic strain–stress relationship a shape memory alloy; Van-der-Pol cycle applied simulate loops. Then, model simply supported alloy beam with damping was proposed. The stability free vibration studied. criterion determining stochastic chaos obtained by random Melnikov approach. To verify theoretical analysis, numerical experiments are carried out. results totally agreed analytical work. Clear fractal boundaries...
The total focusing method (TFM) attracts much interest because of high image resolution and large dynamic range. However, the signal-to-noise ratio (SNR) TFM is relatively low due to single-element emission. Especially in highly attenuating materials, signal amplitude may be reduced with depth a level lower than electronic noise introduced by acquisition system. Golay-coded excitation was overcome this problem, however, double-excitations reduce time lead negative decoding performance...
Ultrasonic guided wave has attracted considerable attention for structural health monitoring (SHM) due to slight propagation loss and sensitivity damage. However, the location imaging accuracy reduces hugely as is often affected by reflection of structure boundary system noise. In this paper, an improving method was established, in which distance coefficient time were proposed select intercept high signal noise ratio data from all experimental data. The effectiveness evaluated experimentally...
Microgripper is a basic kind of mechanical structure and used widely in industries electronics, information technology, optics, medicine, bio-technology. Shape memory alloy (SMA) micro-gripper has high work outputs, higher power-to-weight ratio corrosion resistance, which make it to be attractive solutions for handling micro-parts. However, the traditional SMA can only control through heating cooling. The low energy efficiency slow response speed limit its application engineering fields....
In this work, a probabilistic imaging algorithm based on ellipse method was carried out to locate fatigue crack using nonlinear S0 mode Lamb waves, which modeled by Three-dimensional (3D) Finite Element (FE) Simulation. A as through-thickness seam, and Short-time Fourier transform (STFT) performed the time-domain signals from FE model extract temporal features. damage index (DI) built (PIA) after forming an ellipse-like locus. The ultimate image result showed that location of identified...