To get better gas mileage, engineers are fussing with the structure and composition of tires. The latest advance comes from a material at the beach.
Of all the technology that goes into new cars, tire technology may be the least appreciated. Tires are certainly not the first thing consumers think about when shopping for a car. Indeed, we tend to notice them only when they go flat or wear out. But tires are not just hunks of rubber--they’re a complex blend of materials--and their design is increasingly sophisticated, as automakers push for every edge in fuel economy.
A tire is a horribly complex thing to design, says Dieter Overhoff, an engineer with the Pirelli Armstrong Tire Corporation in Breuberg, Germany. From a physicist’s point of view, we are dealing with a very strange material. The compounds we use don’t behave in a linear fashion. And the interaction of these various compounds is such that you can’t completely describe a tire mathematically. We are in a field in which book law is never valid. And every day we discover that something we knew to be the truth yesterday has been proved wrong today.