Electric Vehicles throw up challenge to engineers
Finland has set the pace for decarbonising the country’s transport Sector by 2050. While the debate is on whether this will be accomplished through electricity or biofuels, the current focus will be on a high percentage of electric vehicles (EV) to develop a carbon-neutral scenario. In this people will weigh the issue of costs such as investment and maintenance of EV and biodiesel cars in making their vehicle choices? Nevertheless, the importance of low rolling resistance (RR) tyres in EV is critical for achieving fuel efficiency and range. In this interview to Tyr Asia, Dr TK Tio, tyre designer, scientist and consultant to the tyre industry worldwide, talks of tyre development for EVs and the challenges before tyre designers and manufacturers
By Dr TK Tio
When it comes to designing and developing low rolling resistance tyres, Dr TK Tio draws from his technology experience accumulated from years of academic and industrial research, which also includes cutting-edge technology from Star War laser development to enhancing tyre performance of his client companies.
This tyre engineer, with double PhDs in Engineering Physics and Tyre Physics, says that in the context of growing vehicle electrification worldwide, there will be a huge surge in demand for tyres specifically designed for EVs.
“Low RR EV tyre is currently a hot topic. Michelin has the only game in town with twenty-five years of head start,” he said. It is a given fact that a 5 per cent reduction in RR translates into about 1 per cent fuel economy boost. RR is the most difficult tyre performance aspect to optimize without hurting other performance parameters.
Low rolling resistance electric vehicle tyre is currently a hot topic. Michelin has the only game in town with a 25-year head start. It is a given fact that a 5 per cent reduction in RR translates into about 1 per cent fuel economy boost. RR is the most difficult tyre performance aspect to optimize without hurting other performance parameters
When asked about the major parameters that tyre engineers should consider while designing EV tyres, he said that stretching the tyre magic triangle to the limit of braking / cornering grips must be on top of their mind.
“Mechanical grip and unconventional/inverted tread design could be important. There is a limit to the aspect ratio in case of EV and sports utility vehicles (SUVs), said the Star War physicist who changed the science of off-road tyre designs.
Dr Tio, who has a BS degree in Mechanical Engineering and a PhD in Engineering Physics, is a specialist on the niche areas such as tyre physics, tyre mechanics and traction physics with special competence in mechanical grip in tyre design. His current research interests are in rubber technology and mixing technology based on macromolecular chemistry and physics and colloid and surface chemistry.
Commenting on the role of natural rubber in EV tyre making and its likely decline in view of the dramatic developments in new composites, Dr Tio affirmed the unique quality of NR. “NR has a unique property of stress-induced crystallization which is essential for TBR and also for off-road tyres in cut-and-chip property.
As EV tyres have to take instant torque, engineers designing tyre should ensure that the vehicle gets more miles out of every watt. “Controlling and balancing the torque to the response and relaxation time of the tyres demand that the rubber should have both soft and hard behaviour. This is one of the top challenges facing tyre engineers
This is the challenge every engineer, particularly those engaged in designing EV tyres has to face while grappling with the perennial issue of the ‘magic triangle’.
The tyre engineer has to look beyond the bulk properties such as tan delta to the tribology / interface physics and chemistry. The hydrophobic wet grip is still Michelin’s deep dark top secret, he commented.
Rubber magic alchemy such as machanochemistry, surface chemistry, colloid chemistry, rheophysics, inorganic chemistry coupled to macromolecular physics and chemistry, etc. all come into play together for custom tyre design
As Richard Phillips Feynman, the American theoretical physicist known for his work in the path integral formulation of quantum mechanics, had said “there were plenty of rooms in the van der Waals down below the mixer / reactor! Johannes Diderik van der Waals, a Dutch theoretical physicist and thermodynamicist famous for his work on an equation of state for gases and liquids, associated with the van der Waals equation of state that describes the behaviour of gases and their condensation to the liquid phase.
Says Dr Tio: “Rubber magic alchemy such as machanochemistry, surface chemistry, colloid chemistry, rheophysics, inorganic chemistry coupled to macromolecular physics and chemistry, etc. all come into play together for custom tyre design.”
The thrill of stretching the tyre magic triangle continues to fire the passion of tyre engineers. Tyre chemistry, rubber compounding and chemical traction are Michelin’s cutting-edge research areas that are second to none, especially in the chemical wet grip in EV tyre, he feels.
“My vision of the future tyre design direction is 4WD + three-peak-mountain with snowflake (3PMSF) = the future of all-weathers and all-terrain mobility.” For the tyre designer, the thrill is in conquering and unifying the integrated science and art of off-road tyre designs.”
(Published on February-March 2018 issue of Tyre Asia)