Energy absorption capability of thin-walled aluminium tubes under crash loading

This paper investigates the interaction of design factors such as tube thickness, tube length, and tube cross-sectional aspect ratio, along with friction and impacting mass on crashworthiness parameters such as specific energy absorption contact time, peak force and crush distance. The impact velocity is assumed to be constant at 15 m/s. The focus is on rectangular aluminium tubes and the analysis was carried out by using a validated finite element model. The analysis shows that the factors are not independent of each other and there is some degree of interaction between them. It was found that the trigger mechanism is a very important design factor to be included in the design of thin-walled tubes for energy absorption applications. The effect of the friction coefficient was found to be insignificant and finally, based on the interactions, it can be concluded that the most effective design would be a larger tube with small wall thickness, and a larger aspect ratio to avoid buckling.Universiti Tenaga Nasional, Malaysi

Energy absorption capabilities of complex thin walled structures

Thin walled structures have been used in the area of energy absorption during an event of a crash. A lot of work has been done on tubular structures. Due to limitation of manufacturing process, complex geometries were dismissed as potential solutions. With the advancement in metal additive manufacturing, complex geometries can be realized. As a motivation, the objective of this study is to investigate computationally the crash performance of complex tubular structures. Five designs were considered. In was found that complex geometries have better crashworthiness performance than standard tubular structures used currently. 1 2017 Published under licence by IOP Publishing Ltd.Scopu

A learning factory: Enhancing societal needs awareness and innovation through manufacturing class

The manufacturing course is a common course in most Mechanical and Industrial Engineering programs around the world. In this course, various aspects of product design and manufacturing process selection are discussed. Students are occasionally given the opportunity to utilize and fabricate some parts by using the discussed manufacturing technologies. To bring further appreciation to the course, the Manufacturing Course in Qatar University has added innovation and entrepreneurship with active learning. Instead of teaching the course material in one daunting block, the faculty (mentor) used a "Just in Time Teaching" strategy by integrating engineering theory and product design within a business plan. The students were divided into groups, and each group had to address a societal need within Qatar. The students were given sessions about idea generation tools and creativity techniques. Once the problem had been identified and formulated, these groups were advised and coached to prepare a comprehensive business plan that included selection of materials, manufacturing processes, organizational structure, marketing of the product, market segmentation and penetration, break-even analysis and economic analysis, as well as environmental issues. From the course assessment and student course outcomes surveys, it was found that the interest and learning curve for students increased drastically for this manufacturing course compared to previous approaches. Besides improving the interest and learning curve, the approach had indirectly exposed the student to project management skills, economic analysis, lifelong learning, communication and teamwork. On the whole, the approach was an interesting and led to further enhancing the student's learning process by using different learning styles through varied and innovative teaching techniques.qscienc

Numerical simulation of a novel expanded metal tubular structure for crashworthiness application

Search for new geometries and materials that would serve in crashworthiness applications is a cumulative process. Recent studies investigated the performance of expanded metal tubes and the possible ways to enhance its energy absorption capability. The aim of this work is to investigate the crashworthiness characteristics of new concept is proposed where expanded metal tube is suited into a double-walled tube made of the same material to form one structure. The tube was then numerically tested through a verified model using ABAQUS software. Moreover, the influence of the size of the expanded metal cell was also investigated in the present study. The new concept showed an enhanced energy absorption characteristics related to the change in the mass of the tubular structure. The enhancement was related to both the change in deformation pattern, and the increase in crushed mass.The authors would like to appreciate the efforts of Qatar University in providing all necessary support.Scopu

New vehicle bumper design for pedestrian protection during impact

This study discusses the influence of the active bumper design on the performance of the selected current bumper in terms of pedestrian protection by using finite element method. The legform impactor is used to test the bumper models created according to EEVC/WG regulations (European Enhanced Vehicle-Safety Committee). The simulation was performed using LS-DYNA. The lower leg injury risk was discussed based on the performance of the bumper. Results of the study show a significant improvement in the bumper performance to mitigate the impact injury of the pedestrian's lower leg.Scopu

Analyzing the Behavior of Classical Functionally Graded Coated Beam

The governing equation of a classical rectangular coated beam made of two homogeneous layers at top ceramic coated layer and bottom metal layer and also single Functionally Graded Material (FGM) as a sub coated layer subjected to uniform distributed mechanical load are derived by using principle of virtual displacements and based on Euler-Bernoulli deformation beam theory (EBT). In FGM layer the material properties are presumed differ as an exponential function form in thickness coordinate. Hence, the aim of this paper is analyzed the static behavior of clamped-clamped thin coated beam under mechanical load.Scopu

Evaluation of bruising susceptibility and response of pears under impact loading through finite element analysis

Mechanical damage and bruising of fruit is a critical problem in the food industry. Minimizing brusing and damage can be achieved by designing energy-absorbing structures and packaging systems in order to ensure the long-term quality of fresh produce. The aim of this study is to investigate the response and bruise susceptibility of pears under impact loading conditions through finite element analysis (FEA) methods. In this paper, three impact heights (0.25 m, 0.5 m, and 1.0 m), four impact material surfaces (poplar wood, rubber, cardboard, and acrylonitrile butadiene styrene (ABS) plastic), two packaging sizes (standard 0.22″ and sandwich lattice 2.1″), and three impact design structures (rigid, corrugated, and honeycomb) are considered. Based on mesh sensitivity analysis, a mesh element of 1.5 mm was adopted for all simulations, assuring the accuracy of results and considering the trade-off between mesh size and computational time. The response surface analysis approach was utilized in order to develop predictive empirical models related to pear bruising. Results revealed that the rubber-based impact platform yielded minimal bruise susceptibility at all heights, while standard-sized corrugated cardboard performed best at a height of 0.25 m. Furthermore, single, double, and triple layers of packaging cardboard were tested. We observed that adding a second soft layer of corrugated cardboard reduced the stress on the pear by around 33%. However, adding a third layer only reduced stress by 5%. The 3D-printed honeycomb ABS has potential as protective packaging but would require further investigations and parameter optimization. Stacking multiple layers of cardboard on top of each other is a cost-effective solution that could improve damping and, therefore, ensure good quality and increase the shelf life of the fresh produce. This study will help decision-makers select the optimal energy-absorbing material for cushioning and packaging designs in order to improve the handling and post-harvesting logistics of fresh produce

Fused Deposition Modelling of Polymer Composite: A Progress

Additive manufacturing (AM) highlights developing complex and efficient parts for various uses. Fused deposition modelling (FDM) is the most frequent fabrication procedure used to make polymer products. Although it is widely used, due to its low characteristics, such as weak mechanical properties and poor surface, the types of polymer material that may be produced are limited, affecting the structural applications of FDM. Therefore, the FDM process utilises the polymer composition to produce a better physical product. The review's objective is to systematically document all critical information on FDMed-polymer composite processing, specifically for part fabrication. The review covers the published works on the FDMed-polymer composite from 2011 to 2021 based on our systematic literature review of more than 150 high-impact related research articles. The base and filler material used, and the process parameters including layer height, nozzle temperature, bed temperature, and screw type are also discussed in this review. FDM is utilised in various biomedical, automotive, and other manufacturing industries. This study is expected to be one of the essential pit-stops for future related works in the FDMed-polymeric composite study. 2022 by the authors.The research was funded by Universiti Malaysia Pahang, grant numbers RDU 1901135, PGRS210367, PGRS210377, and FRGS/1/2019/TK03/UMP/02/15.Scopu

Fused Deposition Modelling of Polymer Composite: A Progress

Additive manufacturing (AM) highlights developing complex and efficient parts for various uses. Fused deposition modelling (FDM) is the most frequent fabrication procedure used to make polymer products. Although it is widely used, due to its low characteristics, such as weak mechanical properties and poor surface, the types of polymer material that may be produced are limited, affecting the structural applications of FDM. Therefore, the FDM process utilises the polymer composition to produce a better physical product. The review’s objective is to systematically document all critical information on FDMed-polymer composite processing, specifically for part fabrication. The review covers the published works on the FDMed-polymer composite from 2011 to 2021 based on our systematic literature review of more than 150 high-impact related research articles. The base and filler material used, and the process parameters including layer height, nozzle temperature, bed temperature, and screw type are also discussed in this review. FDM is utilised in various biomedical, automotive, and other manufacturing industries. This study is expected to be one of the essential pit-stops for future related works in the FDMed-polymeric composite study

A comparative analysis of experimental and numerical investigations of composite tubes under axial and lateral loading

Quasi-static tests are performed in order to determine the crash behavior of composite tubes. The specimens are made from woven fiber carbon/epoxy. The crash experiments show that the tubes crushed in a progressive manner from one end to the other of the tubes while delamination was - taking place between the layers. In the simulation works described in this paper the ANSYS explicit finite element code is used to investigate the compressive properties and crushing response of circular carbon tube subjected to static axial and lateral loading and the results are compared with the experimental work. To better understand the details of the crash process, thin multi layer shell elements are used to model the walls of the circular tube. Finally, the design optimization technique is implemented to find an optimum composite configuration that has the maximum failure load and absorbs the most energy. The crash performance of a carbon composite shell is compared with an optimum carbon tube from the experimental work. 2010, INSInet Publication.Scopu