2nd Edition
Vibration Problems in Machines Diagnosis and Resolution
Vibration Problems in Machines explains how to infer information about the internal operations of rotating machines from external measurements through methods used to resolve practical plant problems. Second edition includes summary of instrumentation, methods for establishing machine rundown data, relationship between the rundown curves and the ideal frequency response function. The section on balancing has been expanded and examples are given on the strategies for balancing a rotor with a bend, with new section on instabilities. It includes case studies with real plant data, MATLAB® scripts and functions for the modelling and analysis of rotating machines.
1. Introduction
1.1 Monitoring and Diagnosis
1.2 Instrumentation
1.3 Mathematical Models
1.4 Machine Classification
1.5 Considerations for a Monitoring Scheme
1.6 Outline of the Text
1.7 Software
1.8 References
2 Data presentation
2.1 Introduction
2.2 Presentation Formats
2.3 Comparison with Calculations
2.4 Detection and Diagnosis Process
2.5 Concluding Remarks
Problems
References
3 Modeling and Analysis
3.1 Introduction
3.2 Need for Models
3.3 Modeling Approaches
3.4 Analysis Methods
3.5 Further Modeling Considerations
3.6 Summary
Problems
References
4 Faults in Machines (1)
4.1 Introduction
4.2 Definitions: Rigid and Flexible Rotors
4.3 Mass Imbalance
4.4 Rotor Bends
4.5 Concluding Remarks
Problems
References
5 Faults in Machines (2)
5.1 Introduction
5.2 Misalignment
5.3 Cracked Rotors
5.4 Torsional Excitation
5.5 Nonlinearity
5.6 Instability
5.7 Interactions and Diagnostics
5.8 Closing Remarks
Problems
References
6. Rotor-Stator Interaction
6.1 Introduction
6.2 Interaction through Bearings
6.3 Interaction via Working Fluid
6.4 Direct Stator Contact
6.5 The Morton Effect
6.6 Harmonics on Contact
6.7 Concluding Remarks
Problems
References
7. Machine Identification
7.1 Introduction
7.2 Current State of Modelling
7.3 Primary Components
7.4 Sources of Error/Uncertainty
7.5 Model Improvement
7.6 Application to Foundations
7.7 Imbalance Identification
7.8 Extension to Alignment
7.9 Future Options
7.10 Concluding remarks
Problems
References
8. Some Further Analysis Methods
8.1 Introduction
8.2 Standard Approaches
8.3 Artificial Neural Networks
8.4 Merging ANNs with Physics-Based Models
8.5 Singular Value Decomposition
8.6 Other Useful Techniques
8.7 Concluding Remarks
Problems
References
9. Case Studies
9.1 Introduction
9.2 A Crack in a Large Alternator Rotor
9.3 Workshop Modal Testing of a Cracked Rotor
9.4 Gearbox Problems on a Boiler Feed Pump
9.5 Vibration of Large Centrifugal Fans
9.6 Low-Pressure Turbine Instabilities
9.7 Concluding Remarks
Problems
References
10. Overview and Outlook
10.1 Progress in Instrumentation
10.2 Progress in Data Analysis and Handling
10.3 Progress in Modeling
10.4 Expert Systems
10.5 Future Prospects
10.6 Summary
References
Solutions to Problems
Index
Biography
Professor Arthur W. Lees graduated in Physics and remained Manchester University for three years research. After completing his PhD , he joined the Central Electricity Generating Board, initially developing Finite Element codes then later resolving plant problems. After a sequence of positions he was appointed head of the Turbine Group for Nuclear Electric Plc. He moved to Swansea University in 1995 and has been active in both research and teaching. He is a regular reviewer of many technical journals and was, until his recent retirement, on the editorial boards of the Journal of Sound & Vibration and Communications on Numerical Methods in Engineering. His research interests include structural dynamics, rotor dynamics, inverse problems and heat transfer. Professor Lees is a Fellow of the Institution of Mechanical Engineers and a Fellow of the Institute of Physics, a Chartered Engineer and a Chartered Physicist. He was a member of Council of the Institute of Physics, 2001-5. He is now Professor Emeritus at Swansea University, but remains an active researcher.
