Numerical evaluation of internal heat generation of roller coaster polyurethane wheels

Nowadays, polymeric materials are used in a wide range of applications such as building and construction, transportation, machinery, electronics. In this paper, the polyurethane, used in roller coaster wheels, was considered and analyzed. The main aim of the research activity is to understand the damaging mechanisms that characterize the material. Experimental results show that the polyurethane can be degraded not only by mechanical fatigue but also by thermal degradation mechanisms which depend on the temperature, caused by both weather conditions and internal heat generation (loss of energy as heat). In particular, the relationship between velocity and intensity of applied loads and the amount of lost energy (lost as heat) was analyzed, with the aim to develop, within a generic finite element analysis code, a methodology to estimate the temperature distribution in a roller coaster wheel, by knowing its load and velocity time history