Practicability of metallic hybrid systems in enhancing the energy absorption capacity: expansion and buckling mechanisms

Abstract

In this paper, the efficiency of a new hybrid design of energy absorber systems is investigated to improve the capability of the system in absorbing the kinetic energy of vehicles in case of a crash. This setup implements two well-known energy absorption mechanisms simultaneously to enhance the energy dissipation capacity of the system while occupying a limited constant space. The system consists of two individual mechanisms, expansion of a circular tube accompanied by buckling of two inner tubes, which dissipates the energy through friction and plastic deformations. This study comprises several case studies surveyed under identical loading conditions. Experimental results are utilized to validate finite element simulations thereby analyzing several case studies so as to achieve the maximum efficiency of the system via geometrical optimizations. This study shows promising outcomes about the improvement in the system capacity in energy absorption while utilizing hybrid systems.

Multi-fidelity crashworthiness optimization of a bus bumper system under frontal impact

“…4. Responses of LF model at 21 training points and response of HF model at randomly selected 10 training points (number 1,4,5,6,7,10,11,13,14,18 shown in Table 3 and Table 4) are used. After generation of multi-fidelity model, the same process as high-fidelity optimization is followed.…”

“…Quadratic response surface model can be expressed as [13] (13) where ŷ(x) is the response prediction, L is the size of input vector x and b 0 , b i , b ii , b ij are the response surface parameters to be determined using linear regression. In order to construct multi-fidelity surrogate models, all data of LF model and data of HF model at randomly selected 10 training points are used (training points number 1,4,5,6,7,10,11,13,14,18 given in Tables 3 and 4 ). After determination of low-fidelity scale factor ( ) and the discrepancy function ( (x)), multi-fidelity surrogate model is constructed as it is explained in Sect.…”

“…Crashboxes are the main energy-absorbing components of the structure, while the bumper beam has more rigid structure to transmit crash energy to the crashboxes in various crash scenarios with a less energy-absorbing capability. Therefore, substantial number of studies is performed on crashboxes with various shapes, such as cylindrical straight tubes [1][2][3], square extrusions [4][5][6] and multi-cell crosssectioned tubes [7][8][9][10][11]. It is found that these structures are efficient energy absorbers that have capability to crush and fold stably.…”