Tyre designers operate in a highly confined parameter space, with their three main performance objectives of friction, wear and adhesion all finely balanced. Improving rolling resistance inevitably occurs with reduced adhesion and greater wear. These constrain just how far designers can move to reduce fuel consumption.
Developments in other vehicle technologies such as improved emergency braking systems and trailer axle steering can help the situation by reducing some of the performance requirements, enabling the tyre design to be optimized in ways previously not possible.
This project will aim to investigate the use of ultra-low rolling resistance tyres that would yield 5-7% reduction in the fuel consumption of heavy goods vehicles, when used in conjunction with improved steering and braking technologies.
(i) Quantify the ‘friction-wear-rolling resistance’ performance and design trade-offs for conventional heavy vehicle tyres,
(ii) Propose trajectories for tyre design optimization, targeting a 30% reduction in rolling resistance, subject to reduced wet grip requirements, as a result of using improved slip-controlled emergency braking technology and axle steering technologies that reduce tyre wear.
The work will result in: (i) Tyre rolling resistance and wear performance data suitable for use in simulations of vehicle and tyre performance; (ii) tyre performance maps quantifying the trade-off between design parameters, (iii) design studies for ultra-low rolling resistance tyres and (iv) development and testing of prototype ultra-low rolling resistance tyres.
Academic impact: Breaking-out of the conventional tyre design parameter space, by improving other aspects of vehicle dynamics, is a novel approach that has not been explored by the tyre industry. This project will develop new experimental evidence and improve understanding of the performance tradeoffs in truck tyre design and will develop new methodologies for designing the combined tyre and vehicle dynamics package. The results will be disseminated through all the main academic channels as well as professional publications.
Commercial and social impact: The potential environmental (fuel consumption) and commercial rewards of this approach are high, but the technical and organizational challenges are substantial.
1. Hunt, S.W., et al., Parameter measurement for heavy vehicle fuel consumption modelling. Proc IMechE Vol 225, Part D: J Auto Eng,, 2011. 225: p. 567-590.
2. Chew, S., Tyre wear in active steering systems. MEng Dissertation 2010, Cambridge University Engineering Department.