Tribological interactions are ubiquitous and have profound impact across all areas of engineering and everyday life. This module places emphasis on the future application of tribological engineering to address the contact mechanics, friction, wear, lubrication and moving interfaces in tribological models, coupling physical phenomena at various scales.
Crucially, advances in tribology have fundamental implications in the emerging innovations for power transmission and electric-mobility, the development of low friction surfaces created for energy saving and the drive for clean/renewable energy systems, such as wind and tidal turbines, wave-powered generator and hydropower. Equally, biotribology which deals with human joint prosthetics, dental materials and skin has a fundamental bearing for our daily lives.
Aims and Objectives
Having successfully completed this module you will be able to:
- Solve problems concerning the hydrodynamic film thickness and friction of plain thrust and journal bearings and other lubricated conformal contacts for e-mobility and biotribology components [EA2, SM4m];
- Solve problems concerning prediction of the wear and fatigue life of future mobility systems [SM1m].
- Solve problems concerning the elastohydrodynamic film thickness in rolling element bearings and other lubricated non-conformal contacts for e-mobility components [EA2];
- Describe the origins and mechanisms of tribological damage [EM1m];
- Explain the differences in tribological design principles between internal combustion engine (using renewable fuels) and electric vehicles [SM1m, SM4m, D2, EL4];
- Analysis and solve problems concerning the pressure, temperature, contact area and friction between rough and smooth bearing surfaces for e-mobility components [EM2m, SM5m];
- Explain and evaluate the origins/characteristics of lubrication regimes related with e-mobility components and conditions [SM4m, EA5m];
Tribological considerations will be key performance factors in future mobility (both hybrid and completely electric vehicles). In hybrid vehicles, tribology plays an important role in the efficiency, emissions and durability of such vehicles, but in pure electric vehicles the concerns over emissions will diminish and nearly all remaining efficiency and durability issues will be associated with the remaining moving parts and, hence, their tribology.
Classic and future areas for tribological engineering will be explored by students. Tribology design principles for e-mobility will be supported and accompanied by advanced case studies using solid/solid and solid/fluid interactions, as well as linking surface and material compatibilities. In turn, this will develop understanding of how surface roughness and surface modifications affect the tribological response of modern engineered components in various industrial and biomedical applications.
Topics to be covered will include:
Smooth and rough surfaces in contact;
Modes of lubrication for bearings and joints;
Tribological systems and components - future engineering implications for electric vehicles and mobility;
Wear mechanisms of dry and lubricated contacts;
Materials selection and tribological design;
Modelling approaches for tribological systems.
Learning and Teaching
Teaching and learning methods
36 lectures (three 45 minute sessions per week) which develop the themes described in this module. Skeleton notes are given out at the start of the course, which means you only have to note down the key points during the lecture, but still have a full set of notes to work from; these will also be made available on Blackboard.
Introduction – provide an future mobility and biotribology context, future engineering implications and impact (electric vehicles (EVs) and renewable energy systems) – outline/link to performance factors between internal combustion engines (ICE) and hybrids/EVs;
Contact mechanics - smooth/rough surfaces in contact under static and in motion, solid friction – wear damage (assessment and quantification within the new electric paradigm);
Modes of lubrication – fluid viscosities and viscous torque – fluids for EVs, plus consideration of future mobility design and optimisation for lubricated systems;
Hydrodynamic lubrication, hydrostatic lubrication, elastohydrodynamic lubrication, mixed and boundary lubrication, identify practical applications for plain bearings, rolling element bearings, gears – bearings for EVs and power transmission within renewable energy systems – design rationales, etc.;
Modelling lubricated joints/bearings – to apply simplified numerical methods to solve tribology problems, and understand how to interpret/verify the results;
Tribological components (gears, bearings) geometries, design and parameters calculation for electric vehicles.
|Completion of assessment task||8|
|Preparation for scheduled sessions||36|
|Wider reading or practice||20|
|Total study time||150|
Resources & Reading list
K. Holmberg, A. Erdemir (2019). The impact of tribology on energy use and CO2 emission globally and in combustion engine and electric cars. Tribology International, 135, pp. 389-396.
L.I. Farfan-Cabrera (2019). Tribology of electric vehicles: A review of critical components, current state and future improvement trends. Tribology International, 138, pp. 473-486.
G.W. Stachowiak and A.W. Batchelor (2014). Engineering Tribology. Butterworth-Heinemann.
J. Williams (2005). Engineering Tribology. Cambridge University Press.
This is how we’ll formally assess what you have learned in this module.
Repeat type: Internal & External