ANALYSIS AND OPTIMIZATION OF AN EXPANDING ENERGY
ABSORBER WITH VARIABLE THICKNESS DISTRIBUTION TUBE
UNDER AXIAL DYNAMIC LOADING |
Yanqing Wang 1, Shiming Wang 2, Lin Hou 3, Yong Peng 2 |
1CRRC Qingdao Sifang Co., Ltd. 2Key Laboratory of Traffic Safety on Track (Central South University), Ministry of Education, School of Traffic & Transportation Engineering, Central South University 4Joint International Research Laboratory of Key Technology for Rail Traffic Safety, Central South University |
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ABSTRACT |
An expanding energy absorber with variable thickness distribution tube is proposed and studied in this work.
At first, a uniform thickness tube structure finite element (FE) model was developed and then verified by the results of an
impact test. The parametric study found that outer obliquity angle β and inner obliquity angle γ have positive influence on
initial peak force (Fp). While as axial distribution ratio l less than 0.1, the l has significant positive effect on Fp. The
non-monotonicity of specific energy absorption (SEA) with design parameters of β and γ was found. Increasing the parameter
l could obviously improve the SEA. To obtain the optimal design, an integrated optimization methodology was applied. The
Pareto fronts show that there is a lot of room for improvement of original design. The optimal compromising solution
increased the SEA by 12.60 % with Fp decreased by 14.24 kN comparing with that of original design. At last, the
optimization result were verified. The study stated that the proposed variable thickness distribution tube of expanding energy
absorber is conducive to improving the crashworthiness of rail vehicles. |
Key Words:
Expanding tube, Variable thickness, Finite element (FE) model, Optimization, Crashworthiness |
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