Topics in Modal Analysis & Testing, Volume 10 (eBook)

Proceedings of the 35th IMAC, A Conference and Exposition on Structural Dynamics 2017

Michael Mains, J.R. Blough (Herausgeber)

eBook Download: PDF

2017 | 1st ed. 2017
VIII, 187 Seiten
Springer International Publishing (Verlag)
978-3-319-54810-4 (ISBN)

Infos

Topics in Modal Analysis & Testing, Volume 10:  Proceedings of the 35^th IMAC, A Conference and Exposition on Structural Dynamics, 2017, the tenth volume of ten from the Conference brings together contributions to this important area of research and engineering.  The collection presents early findings and case studies on fundamental and applied aspects of Modal Analysis, including papers on:

• Operational Modal & Modal Analysis Applications
  
• Experimental Techniques
  
• Modal Analysis, Measurements & Parameter Estimation
  
• Modal Vectors & Modeling
  
• Basics of Modal Analysis
  
• Additive Manufacturing & Modal Testing of Printed Parts 

Michael Mains is Senior Software Developer at Bruel & Kjaer, North America, USA. Jason Blough is Associate Professor in the Department of Mechanical Engineering at Michigan Technological University.

Inhalt

Preface 5
Contents 6
1 Fluid-Structure Interaction in a Labyrinth Gas Seal Coupled to a Flexible Stator 8
Nomenclature 8
1.1 Introduction 9
1.2 Strong Fluid-Structure Coupling 9
1.3 Validation of the Zeroth Order 10
1.4 Stability Analysis 11
1.4.1 Sensitivity to the Radial Clearance and Swirl Velocity 11
1.4.2 Three-Cavities Labyrinth Gas Seal and Sensitivity to the Teeth Position 13
1.5 Conclusion 15
References 16
2 Modal Analysis of Tower Crane with Cracks by the Dynamic Stiffness Method 17
2.1 Introduction 17
2.2 Dynamic Stiffness Modeling of Cracked Beam Element 18
2.2.1 Dynamic Stiffness Method Formulation 18
2.2.2 Dynamic Stiffness Model for Cracked Bar and Beam Elements 19
2.3 Application of the DSM for Tower Crane 22
2.3.1 Governing Equation 22
2.3.2 Effect of Crack on Natural Frequencies of Crane 24
2.4 Conclusion 25
Appendix 1: Formulas for Calculation of Crack Magnitude from Crack Depth 26
Appendix 2: Shape Function for Bar and Beam Elements 27
References 28
3 High-Noise High-Speed Footage Data in Experimental Modal Analysis 29
3.1 Introduction 29
3.2 Measurement Set-up 29
3.3 Optical Flow 30
3.4 Modal Parameter Identification 30
3.5 Results 30
References 31
4 Morlet-Wave Damping Identification: Application to High-Speed Video 32
References 35
5 Fluid-Coupled Vibration Control Inspired by Dragonfly Wings 36
5.1 Introduction 36
5.2 Mechanism 37
5.3 Two Dimensional Wing Flutter Simulation 38
5.4 Conclusion 41
References 41
6 Improving Modal Parameter Estimation by Complementary Output–Output Relations 42
6.1 Introduction 42
6.2 Errors in Variables 43
6.3 Maximum Likelihood Estimator (mle) 45
6.3.1 mle Diagonal Implementation 46
6.4 Extension of Diagonal-mle Using Output–Output Relations 46
6.5 Example Simulation 47
6.5.1 Uncorrelated Outputs 47
6.5.2 Correlated Outputs 48
6.6 Conclusion 48
References 49
7 Operational Modal Analysis in Frequency Domain Using Gaussian Mixture Models 51
Nomenclature 51
7.1 Introduction 51
7.2 Operational Modal Analysis 52
7.2.1 Time-Domain OMA 52
7.2.2 Frequency-Domain OMA 53
7.3 Gaussian Mixture Models (GMM) 53
7.3.1 Bayesian Information Criteria (BIC) 54
7.4 Results 55
7.5 Conclusion 56
References 56
8 Understanding Modal Vectors 58
8.1 Undamped Systems 58
8.2 Matrix Iteration 58
8.3 Orthogonality of Normal Modes 59
8.4 Modal Mass and Vector Scaling 60
8.5 Measurable Frequency Response Functions 61
8.6 Proportionally Damped Models 63
8.7 Non-proportional Damping 64
8.8 Orthogonality of Complex Modes 65
8.9 FRFs from a Complex Mode System 66
8.10 An Alternate Complex-Mode FRF Derivation 68
8.11 Related Observations 70
8.12 Conclusions and Confessions 70
References 71
9 Best Practices for Using Order-Based Modal Analysis for Industrial Applications 72
9.1 Introduction 72
9.2 Order Tracking Techniques 73
9.2.1 Time Domain Sampling Based Fourier Transform Order Tracking (FS) 74
9.2.2 Resampling Based Order Tracking in Order Domain (OT or AD) 75
9.2.3 Other Methods 77
9.3 Order-Based Modal Analysis 78
9.4 Best Practice for Tachometer Measurement and Order Estimation 79
9.4.1 Tachometer Measurement 79
9.4.2 Practical Order Estimation 79
9.5 Validation Cases 80
9.5.1 Locomotive 80
9.5.2 Wind Turbine Gearbox 81
9.5.3 Car Engine Run-up 83
9.6 Conclusions 86
References 87
10 Could the Veering Phenomenon be a Mechanical Design Instrument? 88
10.1 Introduction 88
10.2 The Idea 89
10.3 Model Description 90
10.4 Mode Veering and MAC 91
10.5 Discussion and Design Criterion 91
10.6 Design to Reduce Dynamic Interactions 94
10.7 Conclusions 95
References 98
11 Impulse Excitation of Piezoelectric Patch Actuators for Modal Analysis 99
11.1 Introduction 99
11.2 Characterization of Piezoelectric Impulse Excitation 100
11.2.1 Experimental Set-up 100
11.2.2 Frequency Response Functions Characteristics 101
11.2.3 Modal Parameter Identification 102
11.3 Application to the Modal Analysis of Bladed Disks 104
11.4 Conclusions 106
References 107
12 Modal Parameter Estimation in Multi-Patch Operational Modal Analysis: Perspectives and Approaches 109
Nomenclature 109
Abbreviations 110
12.1 Introduction 110
12.2 Multi-Patch OMA 110
12.2.1 Theoretical Foundations 111
12.3 Singular Value Decomposition Based Patching Methodology 113
12.3.1 Mathematical Formulation 113
12.3.2 Scaling Approaches 114
12.3.3 Method Summary 115
12.4 Experiments 116
12.4.1 Studies on Analytical System 116
12.4.1.1 Description of the System and Simulations 116
12.4.1.2 Results and Discussion 117
12.4.2 Studies on a Steel Plate 124
12.4.2.1 Experiment Design 124
12.4.2.2 Results and Discussion 124
12.5 Further Perspectives on SVD Based Methodology 126
12.6 Conclusions 127
References 128
13 Modeling and Nonlinear Parameter Identification of an Electric-Power Steering System 129
13.1 Introduction 129
13.2 Electric Power Steering (EPS) and Its Functional Model 130
13.3 Experimental Setup and Implementation of the MBST Approach 131
13.4 Parameter Identification and Results 133
13.5 Discussion and Conclusions 135
References 136
14 A Framework for Additive Manufacturing Process Monitoring & Control
14.1 Introduction 138
14.2 Unified DAQ and Control Framework 139
14.3 Part Failure and Correction Methods 140
14.4 Control Feedback Demonstration 141
14.5 Process Monitoring System 142
14.6 Fault Detection Discussion 143
14.7 Conclusions 146
References 146
15 Reliability of Using Stereo Photogrammetry to Estimate Modal Parameters 148
15.1 Introduction 148
15.2 Experimental Modal Analysis Test 148
15.3 Operational Modal Analysis 149
15.3.1 Operational Modal Analysis Using Accelerometers Data 149
15.3.2 Operational Modal Analysis Using Optically Measured Data 150
15.4 Final Remarks 151
References 152
16 Constant Mass Metastructure with Vibration Absorbers of Linearly Varying Natural Frequencies 153
16.1 Introduction 153
16.2 Metastructure Design 154
16.3 Modeling 155
16.3.1 1D Finite Element Model 155
16.3.2 3D Finite Element Model 155
16.4 Results 156
References 157
17 Study on Random Decrement Signature Under Different Triggering Level and Length of Time History 159
17.1 Introduction 159
17.2 Theoretical Basis 160
17.2.1 RDS and Its Variance 160
17.2.2 Quality Assessment of RDS 161
17.3 Simulation Analysis of a SDOF System 161
17.4 Numerical Simulation of a 6-DOF System 164
17.5 Engineering Application 164
17.6 Conclusions 165
References 166
18 Experimental Study on the Rotor Dynamics Influence Upon the Modal Characteristics of an Induction Machine 167
18.1 Introduction 167
18.2 Experimental Setup 168
18.3 Results and Discussions 169
18.4 Conclusions 171
References 171
19 Optimal Modal Parameter Estimation for Highly Challenging Industrial Cases 172
19.1 Introduction 172
19.2 Maximum Likelihood Estimation of a Modal Model: MLMM 173
19.2.1 MLMM Theory 173
19.2.2 Constrained MLMM: Reciprocal Modal Model & Real Mode Shapes
19.2.2.1 Reciprocity Constraint 175
19.2.2.2 Real Mode Shapes 175
19.3 Applications 175
19.3.1 Structural Modal Analysis Applications 176
19.3.1.1 First Fully Equipped Car Example: With a Reasonable Amount of Input Locations 176
19.3.1.2 Second Fully Equipped Car Example: With a Very Large Number of Input Locations 179
19.3.2 Acoustic Modal Analysis Application 182
19.4 Conclusions 186
References 186

Produkt-Details

• Erscheint lt. Verlag: 27.3.2017
• Reihe/Serie: Conference Proceedings of the Society for Experimental Mechanics Series
• Reihe/Serie: Conference Proceedings of the Society for Experimental Mechanics Series
• Zusatzinfo: VIII, 187 p. 154 illus., 135 illus. in color.
• Verlagsort: Cham
• Sprache: englisch
• Themenwelt: Naturwissenschaften ► Physik / Astronomie
• Themenwelt: Technik ► Bauwesen
• Themenwelt: Technik ► Maschinenbau
• Schlagworte: Additive Manufacturing & Modal Testing of Printed Parts • Basics of Modal Analysis • experimental techniques • IMAC Proceedings 2017 • Modal Analysis, Measurements & Parameter Estimation • Modal Vectors & Modeling • Operational Modal & Modal Analysis Applications
• ISBN-10: 3-319-54810-7 / 3319548107
• ISBN-13: 978-3-319-54810-4 / 9783319548104