Numerical Validation of the Combined Extrusion-Splitting Process of Energy Absorption Through Experimental Study

This paper describes the validation process of numerical model of combined collision kinetic energy absorber of rail vehicles based on results of experimental investigations. Combined absorber works on the principle of extrusion-splitting the seamless tube. With the aim to choose the most appropriate tube geometry, the tubes of different geometry of cross-section were made and tested. Key geometry parts have the shape and length of the grooves along the inner tube wall. During the second phase of deformation comes to controlled splitting of the tube wall along these grooves. Experimental and numerical investigations were realised on the scaled samples. Using this type of absorber, energy absorption occurs by friction between absorption elements and elastic-plastic deformation of the tube. Combining the two deformation processes gives a higher absorption power as well as compact dimensions of absorber which can be installed in a very limited space in the front part of the vehicle structure. Creation of the numerical model and numerical simulations of extrusion-splitting processes were realised using SolidWorks and ANSYS LS-Dyna software packages. Results of experimental investigations and numerical simulations show very good agreement which verifies developed numerical model for use in further investigations in this field.