Recently, the concern for safety is increasing as customers’ interest in Run-Flat tires, which can assure their safety in case of a puncture when driving, is growing. Run-Flat tires continues to evolve with the demands of customers who want the performance of general tires such as fuel-consumption and comfort from the basic Run-Flat function in the 1st generation. Run-flat tires are designed in various ways to cope with puncture in pneumatic tires. Currently, Run-flat tires in which Runflat Inserts are inserted into sidewalls of the tires are mainly used. In this study, we would like to propose a method to predict the temperature of sidewall of a Run-flat tires while running and how it affects the durability. We predicted the temperature distribution of sidewall during the running of Run-flat tires by calculating energy loss which is from the viscoelastic characteristic of rubber through deformation analysis of tires, and verified the prediction technique by comparing with the Run-flat endurance test.

The influence of tire belt angle on the Plysteer Residual Aligning Torque(PRAT) and the cornering stiffness by the FEM has been studied. The PRAT is a performance factor of the tire about vehicle pull, and the cornering stiffness has relation to vehicle steering response of outdoor test.
To validate FE model for analysis, simulation data for both the static stiffness(vertical, lateral) and the PRAT have been compared with the experimental data.
In addition to the characteristics of the PRAT and the cornering stiffness due to the tire belt angle, rolling and cornering contact characteristics have been studied. The tendency of the PRAT and the cornering stiffness due to the belt angle can be used as a guide line for the tire design in relation to vehicle pull and vehicle steering response.