Investigation On The Deformation And Energy Absorption Of Thin-Walled Tubes With Cutouts To Axial Impact Loading

Thin-walled metallic tubes, a traditional energy absorption material, have been widely used in the transportation, aerospace, packaging and so on. But in practical engineering, they are often holed for the convenience of connection with other components. Therefore, based on ANSYS and LS-DYNA3D970, the dynamic behavior and energy absorbing properties under axial impact load of single square tube and the multi square tube structures with cutouts are simulated systematically. The main conclusions are shown as follows:The effects of hole position, number of holes and the shape of holes on buckling deformation and energy absorption properties are discussed by the analyzation of some crashworthiness parameters, such as the specific energy absorption (SEA), the compression efficiency (CFE), the average crushing force, the peak crushing force. Compared with that of hollow square tubes without cutout, the initial peak force of tubes with cutout changes slightly, which may be due to the small area of the cutout, but SEA and STE (the total efficiency per unit mass) have a lager variation. For the studied configurations, the configuration with quadrilateral hole in the middle has the best energy absorption property. For the better understanding of energy absorption property of square tubes with hole, the deformation and energy absorption property of square tube with different hole area under some impact velocities are analyzed. Specific energy absorption (SEA), average load and’the initial peak load are compared to derive the formula of the average load. The results show that, compared with the traditional tubes, tubes with hole has almost the same SEA when the hole area is small, however, it of square tubes declines significantly when the the hole area is large. The energy absorption, the initial peak load, the average load and the SEA changes slightly under these three different impact velocities.Energy absorption and dynamic response of multi-square tubes are further investigated under axial loading. It can be concluded that the initial peak force of multi-square tubes with and without hole increases with the increment of impact velocity. The slope of tubes without hole is larger than other configurations. For multi-square tubes with and without hole, the initial peak force has little difference under the low impact velocity, when the impact velocity is high, it of multi-square tubes with hole amplified slightly, which is beneficial to the safety of items. The results also show that, with the condition of same hole number, the initial peak force of multi square tubes with hole position in Lo=0.90L is lower than that of tubes with hole position in Lo=0.50L and Lo=0.70L, with much more steady value of loading-time curve.