Thin-walled structural configurations for enhanced crashworthiness

ABSTRACT

Passenger safety is an important aspect in the design and construction of automobiles. This is achieved in frontal collisions by introducing energy absorbing (EA) structures known as crumple zones or crush cans within the frontal structures that absorb impact energy by controlled plastic deformation and attenuate the intensity of impact during collisions. Although considerable research is carried out till date in developing a variety of EA structures, major limitations in most structures is that they exhibit high initial peak force (F_peak) and low stroke efficiency (SE). This paper aims to develop thin walled EA structural configurations that can weaken the intensity of impact-induced decelerations while maximising the energy absorbed. It initially presents finite element analysis (FEA) of an existing EA structure taken from a literature whose experimental results are available for validation of numerical modelling and analysis procedures. Subsequently, it presents five EA structural configurations, their numerical analyses and assessment of their crashworthiness based on important parameters such as crush force efficiency (CFE), SE and specific energy absorption (SEA). Aluminium alloy AA7005 in T6 state is used for the proposed EA structures. The relative merits of each configuration are discussed based on results of numerical analyses and the best configuration with all-round performance in crashworthiness is recommended.

KEYWORDS:

• Energy absorbing structures
• crashworthiness
• specific energy absorption
• plastic deformation
• crush stroke
• deceleration levels
• initial peak crush force

Acknowledgments

The authors thankfully acknowledge the support provided by BITS-Pilani, Hyderabad Campus and Research Centre Imarat, India, for encouraging a doctoral research on this topic.

Disclosure statement

No potential conflict of interest was reported by the authors.