Similarity design method and multi-objective optimization of train energy-absorbing tube velocity distortion under axial impact.

AbstractThin-walled tubes are commonly used as crucial structures for energy absorption. It is an efficient and convenient research method to establish a small-scale model of the energy-absorbing thin-walled tube for experiments. However, due to the inevitable difference between the design velocity of the test and the actual velocity of the test, it cannot meet the traditional similarity theory. Because of this limitation, this article constructs a similarity design method for the velocity distortion of the multi-cell energy-absorbing tube at the front end of the train under axial impact. Firstly, according to the motion equation of the train system, the design criterion of the similar model under the velocity distortion is derived. Then, the collision mass correction factor is derived based on the elastic-plastic structural energy equation, aiming at the error of the collision peak force and the error of the collision time, the correction factor of the wall thickness of the energy absorbing tube is obtained based on the simulation analysis results. Finally, it is verified that the velocity distortion similarity model can accurately predict the dynamic response of the prototype, and reveals the influence of the mass and wall thickness correction factors on the error. [ABSTRACT FROM AUTHOR]