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.Introduction1.1Monitoring and Diagnosis1.2Instrumentation1.3Mathematical Models1.4Machine Classification1.5Considerations for a Monitoring Scheme1.6Outline of theText1.7Software1.8 References 2Data presentation2.1Introduction2.2Presentation Formats2.3Comparison with Calculations2.4Detection and Diagnosis Process2.5Concluding RemarksProblemsReferences 3Modeling and Analysis3.1 Introduction3.2 Need for Models3.3Modeling Approaches3.4Analysis Methods3.5Further Modeling Considerations3.6SummaryProblemsReferences 4Faults in Machines (1)4.1 Introduction4.2 Definitions: Rigid and Flexible Rotors4.3 Mass Imbalance4.4 Rotor Bends4.5 Concluding RemarksProblemsReferences 5Faults in Machines (2)5.1 Introduction5.2 Misalignment5.3 Cracked Rotors5.4 Torsional Excitation 5.5 Nonlinearity5.6 Instability5.7 Interactions and Diagnostics5.8 Closing RemarksProblemsReferences6. Rotor-Stator Interaction6.1 Introduction6.2 Interaction through Bearings6.3Interaction via Working Fluid6.4Direct Stator Contact6.5The Morton Effect6.6Harmonics on Contact6.7Concluding RemarksProblemsReferences 7. Machine Identification7.1Introduction7.2Current State of Modelling7.3Primary Components7.4 Sources of Error/Uncertainty7.5Model Improvement7.6 Application to Foundations7.7Imbalance Identification7.8Extension to Alignment7.9Future Options7.10 Concluding remarksProblemsReferences 8.Some Further Analysis Methods 8.1Introduction8.2Standard Approaches8.3Artificial Neural Networks8.4Merging ANNs with Physics-Based Models8.5Singular Value Decomposition8.6Other Useful Techniques8.7Concluding RemarksProblemsReferences 9. Case Studies9.1 Introduction9.2A Crack in a Large Alternator Rotor 9.3 Workshop Modal Testing of a Cracked Rotor9.4 Gearbox Problems on a Boiler Feed Pump9.5 Vibration of Large Centrifugal Fans9.6 Low-Pressure Turbine Instabilities9.7 Concluding RemarksProblemsReferences 10.Overview and Outlook10.1 Progress in Instrumentation10.2 Progress in Data Analysis and Handling10.3 Progress in Modeling10.4 Expert Systems10.5 Future Prospects10.6 SummaryReferences Solutions to Problems Index

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.