The course offers a comprehensive and cutting-edge journey through the world of bearings for high-precision and high-speed applications. It covers design, numerical simulation and experimental activities on rolling bearings and fluid-lubricated bearings. Attending the course does not require any prerequisites apart from a basic knowledge of Matlab. Theoretical lectures will introduce Reynolds' equation in its different formulations to explain the fundamentals of fluid-film lubrication. The knowledge acquired will then be used to analyse and learn the main modelling techniques used to simulate the characteristics of different types of bearings for high-precision or high-speed applications. Hands-on laboratory sessions will guide students through the development of experimental characterization techniques. A special focus will be placed on emerging applications of gas bearings in state-of-the-art sectors such as aerospace, high-speed spindles, and precision metrology. The course will be held through: • In-person lectures for advanced theoretical content and direct interaction. • Pre-recorded online modules on the most important topics of the course. • Hands-on lab sessions in small groups focus on numerical implementation and experimental testing. The final evaluation will be based on the following components: 1. Active participation during the course (at least 60% of the course). Attending the lectures of the course and taking part in laboratories is mandatory to get the credits. 2. Short report or oral presentation. The report and the oral presentation are not mandatory and can be carried out by groups of students (up to 5 students). It is worth pointing out that these two activities will be evaluated to pass the examination with merit.

Nessuno

1. Introduction to Bearings and Applications • Overview of bearing types: rolling vs. fluid-film bearings • Key applications: precision machining, aerospace, metrology, turbomachinery • Performance requirements: load capacity, stiffness, damping, speed limits 2. Rolling Bearings Fundamentals • Contact mechanics: Hertzian theory • Lubrication regimes: boundary, mixed, and elastohydrodynamic (EHL) • Thermal and dynamic considerations at high speeds • Design for high-speed applications 3. Fundamentals of Lubricated Bearings • Fluid-film lubrication: incompressible vs. compressible flows • Derivation of the Reynolds equation o Classical Reynolds equation o Modified Reynolds equation for compressible fluids • Boundary conditions and simplifications for different bearing geometries 4. Numerical Modelling • Aerodynamic and Hydrodynamic slider • Aerostatic and Hydrostatic thrust bearings • Dynamic performance and stability (perturbation method and time domain simulations) • Thermal aspects • Fluid-structure interactions 5. Laboratory Activity: Static and dynamic characterization of Aerostatic Thrust bearing Set-up and calibration of air bearing test rigs • Static and dynamic test • Data acquisition and experimental identification techniques 6. Emerging Applications and Future Trends • Air bearings in additive manufacturing and microfabrication • Gas bearings for high-speed applications

Modalitΰ mista

Presentazione orale

P.D.1-1 - Febbraio