Crashworthiness Analysis & Optimization Of The Thin Wall Tube With Regular Folding Patterns

Anti-impact structural properties of energy absorbing unit have been attracting more and more emphasis in fields of collisions accidents such as happing in autos, trains, plates and other vehicles. The capability of energy absorbing units has a direct relationship not only with the quality of the vehicles mentioned above but also with security of the users. Till now, most of energy absorbing units are of smooth walled shell, the ones with regular folding patterns, however, have been not adopted and studied so abroad.To improve design by repeating experiments, most of the traditional researching methods of anti-impact characteristic are featured with obvious shortages such as high cost and long study period. Using technology of high-powered computer and finite element numerical simulation as well the method of structural optimization, this paper, by contrast, has much superiority. The main investigating aspects are as follows:(1) Numerical simulation model of thin shell has been established based on ANSYS/LS-DYNA parametric modeling method. Numerical simulation calculation has carried through following to analyzing changes of absorbed energy.(2) Taking the maximum absorbed energy as the optimization objective; adopting discrete variable searching method-fibonacci searching method, this paper has optimized two kinds of thin wall pipes-the one with polygon section and the one with the first kind of the thin wall tube with regular folding patterns.(3) For pipes with the second kind of tube with regular folding patterns, we've also taken the maximum absorbed energy as the optimization objective and employed response surface method to fit objective function, And the use of quadratic programming algorithm to solve the optimization model.(4) For convenience of relevant designers, optimization software with design interface toward thin wall with regular folding patterns has been compiled, which would lend a strong hand to improving optimization efficiency.Results demonstrate that thin wall pipe with with regular folding patterns has a great advantage over the one without with regular folding patterns. The paper, therefore, academically provides a new direction for seeking excellent anti-impact energy absorbing structures and practically exerts a significant guiding function in vehicle field.