scholarly journals Energy Absorption Enhancement by Unit Cell Angle Grading or Sandwich Panels with Auxetic Core

2022 ◽  
Vol 58 (4) ◽  
pp. 94-101
Author(s):  
Oana Alexandra Mocian ◽  
Dan Mihai Constantinescu ◽  
Florin Baciu ◽  
Andrei Indres

Architectured structures, particularly auxetic materials, have demonstrated encouraging applications in energy absorption as they facilitate the customization of their structural response. Specific geometries of unit cells can thus be tailored for particular needs due to recent progress in additive manufacturing techniques. This paper experimentally studies how the grading of the cell unit angle of an auxetic core in a sandwich panel affects its energy absorbing capability and structural response. 3D printed sandwich panels with uniform and graded auxetic cellular core were tested under quasistatic compression. The results show that sandwich panels with graded core exhibit much better energy absorption capabilities with higher plateau stress and densification strain. This indicates that, by appropriately controlling its geometry, auxetic structures can show further potential as core in sandwich panels for energy absorption applications.

Author(s):  
Benjamin Lewis ◽  
Jonah Leary ◽  
Cynthia Dickman ◽  
Walter Petroski ◽  
Victoria Bellows ◽  
...  

Energy absorption capability of structures with embedded pores depends upon the amount of voids present and their configurations/distributions. In this study, the energy absorption of acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) structures with varying pore shapes and sizes are investigated. The research was performed by two teams comprised of High School/Middle School teachers and undergraduate students as part of National Science Foundation (NSF) sponsored Research Experience for Teacher (RET)/Research Experience for Undergraduates (REU) teams. ABS samples were fabricated by Team 1 and utilized cubic unit cells with octahedral pores while Team 2 fabricated PLA samples that utilized unit cells with spherical pores. Eight sets of samples with dimensions 25mm × 25mm × 20mm were fabricated using a Makerbot Replicator 2X for ABS samples and a Lulzbot TAZ 5 for PLA samples. Each sample incorporated a 5 × 5 × 4 array of pores. All the samples were tested in compression and energy absorption per unit material volume of all the samples up to a particular maximum load was calculated from load-deflection curves. It is observed that the specific energy absorption of PLA and ABS porous structures greatly increases with increased porosity.


2019 ◽  
Vol 20 (3) ◽  
pp. 302 ◽  
Author(s):  
M. Shokri Rad ◽  
Hossein Hatami ◽  
R. Alipouri ◽  
A. Farokhi Nejad ◽  
F. Omidinasab

This paper deals with the effect of unit cell configuration on the energy absorption response of different cellular auxetic structures subjected to quasi-static and dynamic loadings through the experimental and numerical methods. Among the various structures, a re-entrant structure was selected due to its fundamental properties underlying the main characteristics of an auxetic material. Computer simulation techniques using ABAQUS software validated by experimental testing were used to conduct the evaluation of such devices. Several re-entrant structures with different geometrical parameters were modeled and compared with the conventional ones. Standard compression tests were carried out on the different structures produced by the 3D printing machine to evaluate the influence of auxeticity phenomenon in the energy absorption capability. It is discovered that the auxetic structures are superior to non-auxetic structures in terms of all studied impact resistance and energy absorption indicators due to their ability to withstand quasi-static axial impact loads. The primary outcome of this research is to extract design information for the use of auxetic materials as energy absorbers where quasi-static loading is expected.


2018 ◽  
Vol 200 ◽  
pp. 886-909 ◽  
Author(s):  
H. Yazdani Sarvestani ◽  
A.H. Akbarzadeh ◽  
H. Niknam ◽  
K. Hermenean

2019 ◽  
Vol 11 (1) ◽  
pp. 41-68 ◽  
Author(s):  
Chukwuemeke William Isaac

The dynamic oblique crushing of circular thin-walled tubes with the presence of non-propagating crack was investigated numerically. The material considered was strain rate sensitive with crack located at the distal end of the tube. Major crashworthiness parameters were obtained and the analysis of the structural response for idealized and finite element crushed thin-walled tubes was also carried out. The study shows that crack initiation on energy absorbing tubes increase their crushing force efficiency under oblique impact, decrease their crushing force efficiency under axial impact and reduce their crashworthiness performance such as the energy absorption capacity and specific energy absorption under axial and oblique impact. Results of the crashworthiness parameters, deformation modes, damage morphology, stress–strain relations, absorption energy characteristics and crushing force-displacement history were obtained. Furthermore, the numerical study reveals both the desirable and undesirable consequence of crack on the overall crashworthiness performance of energy absorbing circular thin-walled tubes.


Author(s):  
Yang Li ◽  
Zhong You

Sandwich panels, which consist of light core structure in middle and two outside skins, have been widely used for load bearing and energy absorption. Recently, origami foldcores, which can be used as light core structures in sandwich panels, are of interest of many for their open-channel design, continuous manufacturing process, and abundant number of design parameters in comparison with honeycomb and foams. However, one main drawback of origami foldcores is their relatively low energy absorbing capacity. In this paper, we propose a new origami foldcore design, which is based on a zigzag origami pattern known as Miura pattern. The new design has a multi-corrugated shape as its cross-section, and asymmetric dents in it. It achieves a more efficient failure mechanism with both shell buckling and inversing modes, and doubles the energy absorption of Miura pattern foldcore.


2008 ◽  
Vol 11 (5) ◽  
pp. 525-536 ◽  
Author(s):  
Feng Zhu ◽  
Longmao Zhao ◽  
Guoxing Lu ◽  
Zhihua Wang

This paper first presents an experimental investigation into the response of square sandwich panels with an aluminium foam core under blast loading, followed by a corresponding FE simulation using LS-DYNA. In the simulation, the loading process of explosive and response of the sandwich panels have been investigated. The blast loading process includes both the explosion procedure of the charge and interaction with the panel. The simulation result shows that the deformation/failure patterns observed in the tests are well captured by the numerical model, and quantitatively a reasonable agreement has been obtained between the simulation and experiment. Finally, a parametric study has been carried out to investigate the energy absorption performance of sandwich panels.


2021 ◽  
pp. 109863
Author(s):  
J Jefferson Andrew ◽  
Hasan Alhashmi ◽  
Andreas Schiffer ◽  
S Kumar ◽  
Vikram S. Deshpande

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 881
Author(s):  
Adrian Dubicki ◽  
Izabela Zglobicka ◽  
Krzysztof J. Kurzydłowski

Numerous engineering applications require lightweight structures with excellent absorption capacity. The problem of obtaining such structures may be solved by nature and especially biological structures with such properties. The paper concerns an attempt to develop a new energy-absorbing material using a biomimetic approach. The lightweight structure investigated here is mimicking geometry of diatom shells, which are known to be optimized by nature in terms of the resistance to mechanical loading. The structures mimicking frustule of diatoms, retaining the similarity with the natural shell, were 3D printed and subjected to compression tests. As required, the bio-inspired structure deformed continuously with the increase in deformation force. Finite element analysis (FEA) was carried out to gain insight into the mechanism of damage of the samples mimicking diatoms shells. The experimental results showed a good agreement with the numerical results. The results are discussed in the context of further investigations which need to be conducted as well as possible applications in the energy absorbing structures.


Electronics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 494
Author(s):  
Ekaterina Andriushchenko ◽  
Ants Kallaste ◽  
Anouar Belahcen ◽  
Toomas Vaimann ◽  
Anton Rassõlkin ◽  
...  

In recent decades, the genetic algorithm (GA) has been extensively used in the design optimization of electromagnetic devices. Despite the great merits possessed by the GA, its processing procedure is highly time-consuming. On the contrary, the widely applied Taguchi optimization method is faster with comparable effectiveness in certain optimization problems. This study explores the abilities of both methods within the optimization of a permanent magnet coupling, where the optimization objectives are the minimization of coupling volume and maximization of transmitted torque. The optimal geometry of the coupling and the obtained characteristics achieved by both methods are nearly identical. The magnetic torque density is enhanced by more than 20%, while the volume is reduced by 17%. Yet, the Taguchi method is found to be more time-efficient and effective within the considered optimization problem. Thanks to the additive manufacturing techniques, the initial design and the sophisticated geometry of the Taguchi optimal designs are precisely fabricated. The performances of the coupling designs are validated using an experimental setup.


Sign in / Sign up

Export Citation Format

Share Document