Tribology for Future Mobility

Learning Outcomes

Full CEng Programme Level Learning Outcomes

Having successfully completed this module you will be able to:

• As part of the two assignments and final exam, the student must demonstrate knowledge of friction, contact mechanics, lubrication and moving interfaces, and apply to solve tribological problems.
• As part of the two assignments and final exam, the student will analyse the data provided at allow an engineering judgement of the contact mechanics and moving interfaces, in order to formulate and recommend a manufacturing route/strategy.
• As part of the two assignments and final exam, the student must select and justify the appropriate engineering technologies and manufacturing processes to give a desired tribological solution. Equally, they will demonstrate engineering understanding to allow insights and judgement for increased demand for sustainable tribological technologies.
• The two assignments challenge a student to select appropriate design decisions and approaches to find solutions to tribological problems, which must be justified using relevant technical literature.
• As part of the final exam, the student will apply analytical techniques to determine the contact mechanics of either a bearing or gear, plus the kinematics, applying insights linked to the underlying limitations.

Knowledge and Understanding

Having successfully completed this module, you will be able to demonstrate knowledge and understanding of:

• Solve problems concerning the elastohydrodynamic film thickness in rolling element bearings and other lubricated non-conformal contacts for e-mobility components
• Describe the origins and mechanisms of tribological damage
• Analysis and solve problems concerning the pressure, temperature, contact area and friction between rough and smooth bearing surfaces for e-mobility components
• Explain and evaluate the origins/characteristics of lubrication regimes related with e-mobility components and conditions
• Solve problems concerning prediction of the wear and fatigue life of future mobility systems
• 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
• Explain the differences in tribological design principles between internal combustion engine (using renewable fuels) and electric vehicles

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:

Contact mechanics;

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.

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.

Resources & Reading list

Journal Articles

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.

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.

Textbooks

J. Williams (2005). Engineering Tribology. Cambridge University Press.

G.W. Stachowiak and A.W. Batchelor (2014). Engineering Tribology. Butterworth-Heinemann.

Summative

This is how we’ll formally assess what you have learned in this module.

Repeat Information

Repeat type: Internal & External