Fatigue life prediction and optimum topology design of EPDM weather strip

One of the major performances required for weather strip is the high durability against the frequent opening and closing operations of automobile door. In this paper, the fatigue life of automobile weather strip manufactured with EPDM rubber is predicted by making use of the nonlinear finite element analysis and an ε–N curve of EPDM rubber. Furthermore, for the sake of the fatigue life enhancement, the local region within the weather strip cross-section which is vulnerable to the fatigue failure is designed by means of a density-based topology optimization method. Through the numerical experiments, it is confirmed that the topologically optimized weather strips show fatigue lives much longer than the initial weather strip design.

► The fatigue life of EDPM weather strip is predicted by the finite element analysis.
► The topology optimization is performed to improve the fatigue life.
► The fatigue life of the initial weather strip design is improved by 49.08–54.36%.
► The total volume of the initial weather strip design is reduced by 1.73–2.53%.
► The sealing performance is almost kept unchanged after optimization.