It is a challenging task in the design of automobile tires to predict lifetime and performance on the basis of numerical simulations. Several factors have to be taken into account to correctly estimate the aging behavior. This paper focuses on oxygen reaction processes which, apart from mechanical and thermal aspects, effect the tire durability. The material parameters needed to describe the temperature-dependent oxygen diffusion and reaction processes are derived by means of the time–temperature–superposition principle from modulus profiling tests. These experiments are designed to examine the diffusion-limited oxidation (DLO) effect which occurs when accelerated aging tests are performed. For the cord-reinforced rubber composites, homogenization techniques are adopted to obtain effective material parameters (diffusivities and reaction constants). The selection and arrangement of rubber components influence the temperature distribution and the oxygen penetration depth which impact tire durability. The goal of this paper is to establish a finite element analysis based criterion to predict lifetime with respect to oxidative aging. The finite element analysis is carried out in three stages. First the heat generation rate distribution is calculated using a viscoelastic material model. Then the temperature distribution can be determined. In the third step we evaluate the oxygen distribution or rather the oxygen consumption rate, which is a measure for the tire lifetime. Thus, the aging behavior of different kinds of tires can be compared. Numerical examples show how diffusivities, reaction coefficients, and temperature influence the durability of different tire parts. It is found that due to the DLO effect, some interior parts may age slower even if the temperature is increased.
Analysis for tire dynamic response rolling over an obstacle is important to study automobile NVH (Noise‐Vibration‐Harshness), determine vehicle fatigue load, investigate combined longitudinal and sideslip properties, and develop ABS system on uneven roads. Based on the model of Ring on the Elastic and Viscoelastic Foundation (REF) and its analytical solution previously developed, the rolling contact problem between tire/flat and tire/cleat is dealt with in this paper. The static contact problem is treated as the first step to show the effectiveness and accuracy of the model. Then, the time domain simulation of tire rolling contact on uneven roads is conducted. Meirovitch modal analysis method and first‐order matrix perturbation theory are applied to obtain the general forced response of damping REF vibration. An effective numerical quadrature method is developed to obtain the time‐varying modal coordinates of the system under various loading conditions. Numerical examples of a tire rolling over a cleat are given to verify the developed method. It is found that both damping and velocity have strong effects on tire response over a cleat and the frequency of dynamic load is mainly controlled by the first tire mode.