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This paper aims to discuss technically the global trend of labeling legislation and the reflections of governmental programs, such as Inovar Auto, on auto parts industry, in special, about ecolabel intended for tires, focusing advances on rolling resistance analyses and its influence on the fuel consumption of motor vehicles. It will be presented analytical models and theirs respective predicted results to support tire development and researches regarding fuel consumption.

The pneumatic tyre is an important component to the vehicle passenger comfort and safety. It is one of the few mechanical structures subjected to large deflections and deformations. It is manufactured with non-linear anisotropic composite materials, being a complex mechanical structure which presents modeling difficulties such as the contact between tyre and roadway and mathematical complications due to rubber incompressibility and hyperelasticity. The tyre works as the interface between vehicles and the road, being designed to support and transmit the forces generated during the vehicle ride. Accelerations, braking, lateral forces, road irregularities and impact, are ordinary dynamic conditions to the pneumatic structures. The behaviour of a passenger car tyre under impact will be simulated and the forces and deformations generated will be acquired in order to analyze its structural response.

Rubber compound aging is unavoidable. It changes material molecular structure and mechanical properties resulting in undesirable changes in tire performance. The behavior of aged tires was simulated using the finite element method after investigations regarding the boundary conditions, such as temperature, air composition and time of exposure, to reproduce in laboratory the aging observed in the market. During service life, the tire undergoes repeated and complex stress cycles resulting in heat generation by hysteresis. It is critical in regions like belt edges where temperature measurements show values up to 70°C for passenger car tires and more than 100°C for trucks. The inflated air permeates through the tire components leading to oxidative conditions propitious to fatigue and crack propagation. Aging is related to the tire operational conditions but engineers usually accelerate the process in lab tests by increasing the temperature, following the Arrhenius law.