عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Thin-walled tubes have been widely used as energy absorbing devices for decades in trains, passenger cars, ships and other high-volume industrial products since they are relatively cheap and weight efficient. This paper investigates the energy absorption responses of bitubular conical tubes under quasi-static axial and oblique loading. In experimental approach, aluminum bitubular conical tubes were made by the process of spinning. The bitubular conical tubes were fixed at both ends. These samples are compressed between two rigid platens under quasi-static loading conditions and axial and oblique load was realized by applying a load at the upper end of specimens and the collapse mechanism, the variations of crushing load and absorbed energy are determined. A numerical model is presented based on finite element analysis to simulate the collapse process considering the non-linear responses due to material behavior, contact and large deformation. The comparison of numerical and experimental results showed that the present model provides an appropriate procedure to determine the collapse mechanism, crushing load and the amount of energy absorption. The validated finite element model was then used for the parametric studies, in order to determine the effect of bitubular conical tube loading parameters i.e. effect of boundary condition and crush angle. The results of this paper highlight the advantages of using bitubular conical tubes as energy absorber.
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