Abstract:
Transportation and automobiles have become a part of our daily lives and the risks associated
with them of unwanted collision have also increased with automobiles being manufactured at a
very high level all over the world. With the increasing trend of fatalities and injuries caused by
the road traffic accidents, making the vehicles safer has become more critical. In the early years
vehicle were made of solid metals and heavy frames which provided enough occupant protection
but with time the need of making vehicles fuel efficient the low weight requirement has changed
the manufacturing era of automobiles. Although we cannot avoid the occurrence of unwanted
collisions but the impact and severity of crash can be reduced. Thin Walled Columns are
extensively being used in various engineering applications for the purpose of safety requirements
due to their high energy absorption capacity. Their primary purpose is to absorb the excess
amount of impact energy during an unwanted collision undergoing deformation. Numerical
analysis of crushing behavior using Finite Element Module LS-DYNA is carried out to study the
best performance parameters which are specific energy absorption (SEA), mean crushing force
(MCF) and low peak force (PF) by varying different design variables including cross sectional
geometry, thickness and length. The objective is to find the best optimal crash box which
undergoes progressive deformation to absorb collision energy for the application in automobiles
to enhance the safety for passenger cabin. To study the effect of number of corners on
crashworthiness parameters, polygons having 5 to 8 corners are numerically analyzed and the
best of them is further numerically investigated with circular, rectangle and square cross
sectional shape. Thin walled tube having hexagonal cross section is found to be the best for
energy absorption under axial impact loading while comparing selected crashworthiness
parameters.
