Vol. 37, No 2

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Limitations of Shell models in Composite Reinforced Fibre using FEA analysis 

Dennis, L  Amir, K

 Abstract

The limitations of shell models in composite FEA analysis was analysed in term of defining when to progress to full 3D models and how effectively to build them. This was achieved through reviewing  literature review data to analyse the previously adopted FEA tools for shell analyses in order to theoretically indicate their limitations. This can be validated by comparing them to the results of the experimental tools. Also, Various CAD modelling tools will be used to build CAD models for the shells and analysing them. The obtained results from these CAD models were then compared to make a decision regard the best CAD tool for shell analyses. An expectation can be made regard the suitable tools which SOLIDWORKS and ANSYS software. 

Comparison is CAD/FEA techniques for Composites Beams

Yakun, G Eduardo, T  Sam, N  Rayan, N

 Abstract

The design and analyses techniques for composite beams are significantly more complex than those used for metallic structures; this because of the large number of dissimilar composite materials in addition to the anisotropic nature of characteristic composite materials. A lot of composite design techniques have been developed by different researches in order to automate calculations for the properties and behaviour of standard composite structures. In this project, the available CAD/FEA techniques for composite beams modelling and analyses were reviewed and compared to show the best techniques that provides best results. Solidworks and ANSYS software were used as a CAD/FEA software’s to model a certain composite beam and testing its performance. 

Li, W  Wang, A  Zhang, A

 Abstract

  Foams are constructed from cellular core structure; this structure resulted from blowing agent expansion. It mainly made of two phases or more; one is a polymer matrix and the other is gaseous voids that may called in some types ‘bubbles’. Gaseous voids enclosed by open-cell or closed-cell structure. It is clear to investigate that; bubbles of gaseous voids are completely covered in case of the closed-cell structure type (rigid) while they are not closed in case of the structure of the cell is open-cell structure type (flexible). Bubbles existence reduces the overall cost of the material as the volumetric occupancy by foams is decreased, it is the selection base of foams. Foam provides a high thermal insulation performance because of its lower coefficient of conductivity and economic benefits .   Artificial Sponge is the closed-cell structure type of foams, it is more rigid and provides higher mechanical properties. On the other hand, the economic benefits obtained from the foams decreased due to the increase in mass for the closed-cell structure. Provided thermal insulation performance is unique if compared with the other elastomer materials, sponges characterized by its extended lifetime as well  

Geev, Y    Pete, F 

 Abstract

 This paper discusses the differential equations of linear systems with and without damping. Firstly, the behaviour of a linear discrete system in single degree of freedom is analyzed. A spring mass damper system is used as a prototype. The mass has no damping or damper has no mass and the mass moves in only one direction. The features of viscous damping are discussed carefully. This leads to the study of free vibration and forced steady state vibration of single degree of freedom systems, clearly explaining the peculiar differences of both. Next, the property of multiple degree of freedom systems are analyzed which leads to the eigenvalue problem and the modal decomposition of the stationary response. Furthermore, the distributed parameter systems are discussed. The paper ends with the discussion of a special type of system: transversal vibration of cantilever beams. The carried out numerical analyses for the motion of the 2-DOF pendulum was obtained using MATLAB software at different initial conditions. By changing the angles at which the rod made by a vertical reference line, the position of the two bobs in the x and y direction was changed and showed Chaotic response in certain conditions.