Heat build-up and thermo-mechanical fatigue life optimization of aircraft tire using deformation index concept

Abstract

Aircraft tires are a critical component for the takeoff, landing, and taxiing of an aircraft. Under high-speed and heavy-load conditions, aircraft tires are subjected to huge stresses and remarkable heat build-up. Improving tire safety and service life is crucial. The deformation index can be used to judge the control modes of different components of the tire, such as strain control, stress control, or energy control. This study details the calculation of the deformation index and emphasizes the need to vary only stiffness while holding viscoelastic parameters constant during perturbation analysis. Combined with the finite element analysis and the user-defined subroutine, the contour plot of the deformation index in each component of the aircraft radial tire under certain load, pressure, and speed conditions was obtained. On this basis, material stiffness optimized schemes for typical components in tire (such as tread, cushion, and innerliner) were proposed based on the thermo-mechanical coupling analysis method of heat build-up and fatigue life. The systematic results confirm the effectiveness of using the deformation index to improve the fatigue life of aircraft tires. When the stiffness of the tread and cushion rubber are increased by 50 % and 30 %, respectively, and the stiffness of the innerliner rubber is reduced by 50 %, the highest temperature in the shoulder region is reduced by 4.17 °C, and the fatigue life of the aircraft tire is even increased by five times.