Wieslaw Ostachowicz, Pawel Kudela, Marek Krawczuk

Guided Waves in Structures for SHM

The Time-Domain Spectral Element Method

• Gebundenes Buch

Produktbeschreibung

Understanding and analysing the complex phenomena related to elastic wave propagation has been the subject of intense research for many years and has enabled application in numerous fields of technology, including structural health monitoring (SHM). In the course of the rapid advancement of diagnostic methods utilising elastic wave propagation, it has become clear that existing methods of elastic wave modeling and analysis are not always very useful; developing numerical methods aimed at modeling and analysing these phenomena has become a necessity. Furthermore, any methods developed need to be verified experimentally, which has become achievable with the advancement of measurement methods utilising laser vibrometry.

Guided Waves in Structures for SHM reports on the simulation, analysis and experimental investigation related propagation of elastic waves in isotropic or laminated structures. The full spectrum of theoretical and practical issues associated with propagation of elastic waves is presented and discussed in this one study.

Key features:
Covers both numerical and experimental aspects of modeling, analysis and measurement of elastic wave propagation in structural elements formed from isotropic or composite materials
Comprehensively discusses the application of the Spectral Finite Element Method for modelling and analysing elastic wave propagation in diverse structural elements
Presents results of experimental measurements employing advanced laser technologies, validating the quality and correctness of the developed numerical models
Accompanying website (www.wiley.com/go/ostachowicz) contains demonstration versions of commercial software developed by the authors for modelling and analyzing elastic wave propagation using the Spectral Finite Element Method

Guided Waves in Structures for SHM provides a state of the art resource for researchers and graduate students in structural health monitoring, signal processing and structural dynamics. This book should also provide a useful reference for practising engineers within structural health monitoring and non-destructive testing.

Produktdetails

• Verlag: Wiley & Sons
• 1. Auflage
• Seitenzahl: 352
• Erscheinungstermin: 13. Februar 2012
• Englisch
• Abmessung: 234mm x 157mm x 23mm
• Gewicht: 580g
• ISBN-13: 9780470979839
• ISBN-10: 0470979836
• Artikelnr.: 34440428

Autorenporträt

Wieslaw Ostachowicz, Pawel Kudela, Marek Krawczuk, Zak Arkadiusz, Polish Academy of Sciences, Polandbr />Wieslaw Ostachowicz is Professor and Head of the Department of Mechanics of Intelligent Structures in the Institute of Fluid Flow Machinery at the Polish Academy of Sciences. His research areas include structural health monitoring, vibration control and damage control, structural dynamics, smart materials and structures, composite structures and fracture mechanics. He is on the editorial boards of Composites Part B: Engineering, Strain, Mechanical Engineering Science, Smart Materials and Structures and Structural Health Monitoring. All three co-authors are are members of Professor Ostachowicz's research team within Institute of Fluid Flow Machinery at the Polish Academy of Sciences. Pawel Kudela is a Ph.D. senior researcher at the Institute of Fluid Flow Machinery at the Polish Academy of Sciences. Marek Krawczuk is Professor at the Institute of Fluid Flow Machinery at the Polish Academy of Sciences. Arkadiusz Zak is an associate professor at the Institute of Fluid Machinery at the Polish Academy of Sciences.

Inhaltsangabe

Preface ix 1 Introduction to the Theory of Elastic Waves 1 1.1 Elastic
Waves 1 1.1.1 Longitudinal Waves (Compressional/Pressure/Primary/P Waves) 2
1.1.2 Shear Waves (Transverse/Secondary/S Waves) 2 1.1.3 Rayleigh Waves 3
1.1.4 Love Waves 4 1.1.5 Lamb Waves 4 1.2 Basic Definitions 5 1.3 Bulk
Waves in Three-Dimensional Media 10 1.3.1 Isotropic Media 10 1.3.2
Christoffel Equations for Anisotropic Media 12 1.3.3 Potential Method 14
1.4 Plane Waves 15 1.4.1 Surface Waves 16 1.4.2 Derivation of Lamb Wave
Equations 17 1.4.3 Numerical Solution of Rayleigh-Lamb Frequency Equations
26 1.4.4 Distribution of Displacements and Stresses for Various Frequencies
of Lamb Waves 29 1.4.5 Shear Horizontal Waves 32 1.5 Wave Propagation in
One-Dimensional Bodies of Circular Cross-Section 35 1.5.1 Equations of
Motion 35 1.5.2 Longitudinal Waves 36 1.5.3 Solution of Pochhammer
Frequency Equation 39 1.5.4 Torsional Waves 42 1.5.5 Flexural Waves 43
References 45 2 Spectral Finite Element Method 47 2.1 Shape Functions in
the Spectral Finite Element Method 53 2.1.1 Lobatto Polynomials 54 2.1.2
Chebyshev Polynomials 56 2.1.3 Laguerre Polynomials 60 2.2 Approximating
Displacement, Strain and Stress Fields 62 2.3 Equations of Motion of a Body
Discretised Using Spectral Finite Elements 67 2.4 Computing Characteristic
Matrices of Spectral Finite Elements 72 2.4.1 Lobatto Quadrature 75 2.4.2
Gauss Quadrature 76 2.4.3 Gauss-Laguerre Quadrature 78 2.5 Solving
Equations of Motion of a Body Discretised Using Spectral Finite Elements 81
2.5.1 Forcing with an Harmonic Signal 82 2.5.2 Forcing with a Periodic
Signal 83 2.5.3 Forcing with a Nonperiodic Signal 84 References 92 3
Three-Dimensional Laser Vibrometry 93 3.1 Review of Elastic Wave Generation
Methods 94 3.1.1 Force Impulse Methods 94 3.1.2 Ultrasonic Methods 94 3.1.3
Methods Based on the Electromagnetic Effect 97 3.1.4 Methods Based on the
Piezoelectric Effect 98 3.1.5 Methods Based on the Magnetostrictive Effect
102 3.1.6 Photothermal Methods 103 3.2 Review of Elastic Wave Registration
Methods 104 3.2.1 Optical Methods 106 3.3 Laser Vibrometry 109 3.4 Analysis
of Methods of Elastic Wave Generation and Registration 114 3.5 Exemplary
Results of Research on Elastic Wave Propagation Using 3D Laser Scanning
Vibrometry 116 References 121 4 One-Dimensional Structural Elements 125 4.1
Theories of Rods 125 4.2 Displacement Fields of Structural Rod Elements 127
4.3 Theories of Beams 133 4.4 Displacement Fields of Structural Beam
Elements 135 4.5 Dispersion Curves 141 4.6 Certain Numerical Considerations
143 4.6.1 Natural Frequencies 144 4.6.2 Wave Propagation 147 4.7 Examples
of Numerical Calculations 155 4.7.1 Propagation of Longitudinal Elastic
Waves in a Cracked Rod 156 4.7.2 Propagation of Flexural Elastic Waves in a
Rod 158 4.7.3 Propagation of Coupled Longitudinal and Flexural Elastic
Waves in a Rod 162 References 164 5 Two-Dimensional Structural Elements 167
5.1 Theories of Membranes, Plates and Shells 167 5.2 Displacement Fields of
Structural Membrane Elements 169 5.3 Displacement Fields of Structural
Plate Elements 175 5.4 Displacement Fields of Structural Shell Elements 181
5.5 Certain Numerical Considerations 184 5.6 Examples of Numerical
Calculations 189 5.6.1 Propagation of Elastic Waves in an Angle Bar 189
5.6.2 Propagation of Elastic Waves in a Half-Pipe Aluminium Shell 192 5.6.3
Propagation of Elastic Waves in an Aluminium Plate 195 References 198 6
Three-Dimensional Structural Elements 201 6.1 Solid Spectral Elements 202
6.2 Displacement Fields of Solid Structural Elements 202 6.2.1 Six-Mode
Theory 202 6.2.2 Nine-Mode Theory 203 6.3 Certain Numerical Considerations
204 6.4 Modelling Electromechanical Coupling 208 6.4.1 Assumptions 213
6.4.2 Linear Constitutive Equations 213 6.4.3 Basic Equations of Motion 214
6.4.4 Static Condensation 215 6.4.5 Inducing Waves 216 6.4.6 Recording
Waves 216 6.4.7 Electrical Boundary Conditions 216 6.5 Examples of
Numerical Calculations 220 6.5.1 Propagation of Elastic Waves in a
Half-Pipe Aluminium Shell 220 6.5.2 Propagation of Elastic Waves in an
Isotropic Plate - Experimental Verification 222 6.6 Modelling the Bonding
Layer 227 References 230 7 Detection, Localisation and Identification of
Damage by ElasticWave Propagation 233 7.1 Elastic Waves in Structural
Health Monitoring 235 7.2 Methods of Damage Detection, Localisation and
Identification 247 7.2.1 Energy Addition Method 253 7.2.2 Phased Array
Method 255 7.2.3 Methods Employing Continuous Registration of Elastic Waves
within the Analysed Area 263 7.2.4 Damage Identification Algorithms 266 7.3
Examples of Damage Localisation Methods 269 7.3.1 Localisation Algorithms
Employing Sensor Networks 269 7.3.2 Algorithms Based on Full Field
Measurements of Elastic Wave Propagation 275 References 288 Appendix:
EWavePro Software 295 A.1 Introduction 295 A.2 Theoretical Background and
Scope of Applicability (Computation Module) 296 A.3 Functional Structure
and Software Environment (Pre- and Post-Processors) 298 A.4 Elastic Wave
Propagation in aWing Skin of an Unmanned Plane (UAV) 312 A.5 Elastic Wave
Propagation in a Composite Panel 320 References 333 Index 335