The Analysis of a Polyurethane Tunnel-Type Shock Absorber Operating Under Shock Loading

This paper presents the results of bench shock tests of a polyurethane tunnel-type shock ab-sorber designed for use in complex dynamic systems. Using overload and displacement sen-sors readings, shock power characteristics of the shock absorber were determined. The shock absorber was subjected to a vertical impact by a heavy falling plate on a specially designed testing stand. The process of the shock absorber deformation was recorded using a high-speed camera. Images illustrating the deformation were presented. To develop a reliable mathematical model of the shock absorber, shock loading calculations were performed using the finite element method in the ANSYS environment and applying the characteristics of polyurethane obtained through experiments. The calculated and the experimental results were compared with regards to the loading characteristics of the shock absorber as well as the values of energy accumulated and absorbed by the shock absorber at impact. It was shown that the developed mathematical model could be used to calculate shock characteristics of the shock absorber in the analysed range of the rate of deformation. The model can be used at the design stage when selecting geometrical parameters of the shock absorbers guaranteeing the required load characteristics.

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