Advanced Dynamics Of Rolling Elements

In any rotating machinery system, the bearing has traditionally been a crit ical member of the entire system, since it is the component that permits the relative motion between the stationary and moving parts. Depending on the application, a number of different bearing types have been used, such as oil-lubricated hydrodynamic bearings, gas bearings, magnetic suspensions, rolling element bearings, etc. Hydrodynamic bearings can provide any desired load support, but they are limited in stiffness and the associated power loss may be quite large. Gas bearings are used for high-precision applications where the supported loads are relatively light, bearing power losses are very low, and the rotating speeds generally high. For super precision components where no frictional dissipation or bearing power loss can be tolerated, magnetic suspensions are employed; again, the load support requirements are very low. Rolling element bearings have been widely used for those applications that require greater bearing versatility, due to the requirements for high-load and high-stiffness characteristics, while allowing moderate power loss and permitting variable speeds. A study of the dynamic interaction of rolling elements is, therefore, the subject of this text. Texts covering the analysis and design methodology of rolling elements are very limited. Notable works include Analysis of Stresses and Deflections (Jones, 1946, Vols. I and II), Ball and Roller Bearings, Their Theory, Design and Application (Eschmann, Hasbargen, and Weigand, 1958), Ball and Roller Bearing Engineering (Palmgren, 1959, 3rd ed. ), Advanced Bearing Technology (Bisson and Anderson, 1965), and Rolling Bearing Analysis (Harris, 1966).

A new mathematical model is proposed to examine the vibration transmission through rolling element bearings in geared rotor systems. Current bearing models, based on either ideal boundary conditions for the shaft or purely translational stiffness element description, cannot explain how the vibratory motion may be transmitted from the rotating shaft to the casing. For example, a vibration model based upon the simple bearing formulations can only predict purely in-plane type motion on the flexible casing plate given only bending motion on the shaft. However, experimental results have shown that the casing plate motion is primarily flexural. This study clarifies this issue qualitatively and quantitatively by developing a comprehensive bearing stiffness matrix is partially verified using available analytical and experimental data, and is completely characterized. This study extends the proposed bearing formulation to analyze the overall geared rotor system dynamics including casting and mounts. The bearing stiffness matrix is included in discrete system models using lumped parameter and/or dynamic finite element techniques. Eigensolution and forced harmonic response due to rotating mass unbalance or kinematic transmissions error excitation for the following examples are computed: (I) single-stage rotor system with flexible shaft supported by two bearings on rigid casing and flexible mounts, (II) spur gear pair system with motor and load inertials attached to two flexible shafts and supported by four bearings on flexibly mounted rigid casing, and (III) case II with flexible casing and rigid mounts. In several of these examples, analytical predictions compare well with measured data, validating the purposed formulation.

Specifically focusing on fluid film, hydrodynamic, and elastohydrodynamic lubrication, this edition studies the most important principles of fluid film lubrication for the correct design of bearings, gears, and rolling operations, and for the prevention of friction and wear in engineering designs. It explains various theories, procedures, and equations for improved solutions to machining challenges. Providing more than 1120 display equations and an introductory section in each chapter, Fundamentals of Fluid Film Lubrication, Second Edition facilitates the analysis of any machine element that uses fluid film lubrication and strengthens understanding of critical design concepts.

This volume gathers the latest advances, innovations and applications in the field of condition monitoring, plant maintenance and reliability, as presented by leading international researchers and engineers at the 5th International Conference on Maintenance Engineering and the 2020 Annual Conference of the Centre for Efficiency and Performance Engineering Network (IncoME-V & CEPE Net-2020), held in Zhuhai, China on October 23-25, 2020. Topics include vibro-acoustics monitoring, condition-based maintenance, sensing and instrumentation, machine health monitoring, maintenance auditing and organization, non-destructive testing, reliability, asset management, condition monitoring, life-cycle cost optimisation, prognostics and health management, maintenance performance measurement, manufacturing process monitoring, and robot-based monitoring and diagnostics. The contributions, which were selected through a rigorous international peer-review process, share exciting ideas that will spur novel research directions and foster new multidisciplinary collaborations.

The future market forces and environmental considerations in the passenger car and commercial vehicle sector mean more stringent engine downsizing is far more prevalent. Therefore, novel systems are required to provide boosting solutions including hybrid, electric-motor and exhaust waste energy recovery systems for high efficiency, response, reliability, durability and compactness. The current emission legislations and environmental trends for reducing CO2 and fuel consumption are the major market forces in the land and marine transport industries. The internal combustion engine is the key product and downsizing, efficiency and economy are the driving forces for development for both spark ignition (SI) and compression ignition (CI) engines in both markets. Future market forces and environmental considerations for transportation, specifically in the passenger car, commercial vehicle and the marine sectors mean more stringent engine downsizing. This international conference is the latest in the highly successful and prestigious series held regularly since 1978. These proceedings from the Institution’s highly successful and prestigious series address current and novel aspects of turbocharging systems design, boosting solutions for engine downsizing and improvements in efficiency, and present the latest research and development in this growing and innovative area. Focuses on boosting solutions including hybrid, electric-motor and exhaust waste energy recovery systems Explores the current need for high efficiency, reliability, durability and compactness in recovery systems Examines what new systems developments are underway

Bearings: from Technoloogical Foundations to Practical Design Applications provides a modern study of bearing types, design factors, and industrial examples. The major classes of bearings are described, and design concepts are covered for rolling elements, surfaces, pivots, flexures, and compliance surfaces. Fluid film lubrication is presented, and the basics of tribology for bearings is explained. The book also looks at specific applications of bearing technology, including bearings in vehicles, rotating machinery, machine tools, and home appliances. Case studies are also included.