Tribology

Code	7150
Year	1
Semester	S2
ECTS Credits	6
Workload	T(30H)/TP(30H)
Scientific area	Mechanics and Thermodynamics
Entry requirements	In order to attend this course the student must have previous knowledge of Fluid Mechanics, Applied Mechanics and Materials Science.
Mode of delivery	Presential.
Work placements	Not applicable.
Learning outcomes	Introduction and development of the fundamental concepts of Tribology, focusing on the application of the theory of lubrication to predictive maintenance and design of mechanical systems. In this context the student must: 1. demonstrate awareness and understanding about surfaces and their characterization, contact and wear, roughness parameters and their measurement, lubricants and lubrication systems and, finally, about the selection and calculation of bearings; 2. be able to measure a surface roughness and determine the viscosity of a lubricating oil; 3. adequately analyze a surface texture and identify the proper lubrication regime; 4. be able to apply the skills acquired to select a journal bearing; 5. consult with scientific journals and experimental techniques in their achievements.
Syllabus	1) Lubrication: historical perspective. Surfaces: nature and properties. Contact between surfaces. Lubrication regimes. 2) Geometry and texture of surfaces. Equipment for surface profile measurement. Basic and statistical parameters for roughness characterization. Reference lines. Typical values. Abbot Diagram. Auto-correlation function. Influence of roughness on the lubrication regime. 3) Solid, liquid and gas lubricants. Properties of lubricating fluids. Oils and greases. 4) Theory of lubrication. Fluid film lubrication theory. “Creeping" flow. Stokes equations. Petrov Law. Sommerfeld's number. Dimensionless film parameter. Reynolds equations. Physical meaning of relevant terms in these equations. 5) Bearings. Description and classification of bearings. Methodology for selection of bearings. Calculation of bearings. Michell's tilting pad bearing. 6) Experimental study: Analysis of a metallic surface (Hommel Tester T1000).
Main Bibliography	1. A. C. Mendes, Tribologia - Fundamentos de Teoria da Lubrificação, Universidade da Beira Interior, Covilhã (2009). 2. R. D. Arnell, P. B. Davies, J. Halling e T. L. Whomes, Tribology, Principles and Design Applications, MacMillan Education Ltd., London (1991). 3. A. Cameron, Basic Lubrication Theory, Ellis Horwood Limited, 2nd Ed., Chichester (1976). 4. B. J. Hamrock, Fundamentals of Fluid Film Lubrication, McGraw-Hill International Editions, Singapore (1994). 5. J. E. Shigley e C. R. Mischke, Mechanical Engineering Design, 5ª. Ed. McGraw-Hill International Editions (1989). 6. D. F. Moore, Principles and Applications of Tribology, Pergamon Press Ltd., Oxford (1975). 7. K. E. Banister, Lubrication for Industry, Industrial Press, Inc., New York (1996). 8. U. J. Moller e U. Boor, Lubricants in Operation (edited by A. R. Lansdown), Mechanical Engineering Publications Limited, London (1996). 9. M. J. Neale (ed.), The Tribology Handbook, Butterworth-Heinemann Ltd., 2nd Ed., Oxford (1995).
Language	Portuguese. Tutorial support is available in English.