Análise de um dispositivo de absorção de impacto para a traseira de um ônibus elétrico através de simulação numérica

Abstract

The present work aimed to analyze the behavior of the region of the rear structure of an electric bus in a collision situation based on the pendulum test according to resolution No. 629 of CONTRAN (2016) and created mechanisms capable of absorbing the energy generated by the impact in order to guarantee the integrity of the electric traction batteries that are allocated there, preventing possible leaks of flammable electrolytes and even starting a fire if damaged. Studies were carried out on tubular section profiles with triggers for deformation (triggers), called crash boxes (which aim to convert kinetic energy into deformation energy). Seven proposals were created based on authors who studied different concepts on the subject. For the modeling of the proposals, the SolidWorks 2019 software was used and the behavior of each one was numerically evaluated through the ANSYS LS-DYNA software. From these studies, it was possible to obtain reductions of up to 148% regarding Pmax values and an increase of up to 43% of Pmed compared to a square tube of the same cross section. After the individual simulations of the crash boxes, the three best ones were applied to the structure along with load paths that served to direct the residual energy to more rigid regions such as the chassis spars and joining beams between the bodywork. The proposals even converted up to 45% of the kinetic energy into deformation energy and met the approval criteria that was to ensure that no component of the structure touched the batteries during impact, unlike the current structure that failed to damage the batteries. [resumo fornecido pelo autor]