Design and Fabricate Filament Winding Machine and Analysis of Cotton/Epoxy and Pandanus/Epoxy

This project concerned with filament wound cotton/epoxy and pandanus/epoxy composite tubes. Monofilament winding machine has been designed and fabricated. It is later used in fabricating the composite tubes. The performance of this machine was measured. The results revealed that the winding angle depended primarily on the carriage speed traversing at speed synchronised with mandrel rotation. Also, the efficiency of the machine showed that winding at high angles relative to rotational axis was very high (i.e. at 90° the efficiency is 100%). Winding at low angles (parallel to rotational axis) was difficult. The surface finish depended on the fibre tension, the wiping process and band formation 0. e. smooth surface finish at 4.4 kN). The behaviour of filament wound cotton/epoxy and pandanus/epoxy composite tubes was studied experimentally. Circular cylindrical of cotton/epoxy and pandanus/epoxy were loaded in uni-axial compression. The test results show that cotton/epoxy hoop tubes the maximum strength was found to be 13kN and for the 80° cotton/epoxy tubes was found to be 10.6kN. For the pandanus/epoxy hoop tube the maximum strength was found to be 0.3kN. Flat specimens were also prepared from wound tubes and loaded in uni-axial tension. The cotton/epoxy composite tubes were tested under internal pressure. The results show that the maximum pressure that the tube can be withstand was found to be 5 bar. Maximum stress and maximum strain theories are used to predict the failure of these tubes. Finite element method also used in the analysis of cotton/epoxy composite tubes. The uni-axial tensile test results show that the mean modulus was found to be 3 867.6 MPa for the 80° laminated tensile test specimens and 1067.0 MPa for hoop (90°) laminated tensile test specimens. The maximum strain mean in 80° and 90° laminated tensile specimens are essentially the same (0.1). The urn-axial compression test results show that in the condition of hoop (90°) laminated tubes and 80° laminated tubes the load-displacement curve is linearly up to initial failure

A Naïve-Bayes classifier for damage detection in engineering materials

This paper is intended to introduce the Bayesian network in general and the Naïve-Bayes classifier in particular as one of the most successful classification systems to simulate damage detection in engineering materials. A method for feature subset selection has also been introduced too. The method is based on mean and maximum values of the amplitudes of waves after dividing them into folds then grouping them by a clustering algorithm (e.g. k-means algorithm). The Naïve-Bayes classifier and the feature sub-set selection method were analyzed and tested on two sets of data. The data sets were conducted based on artificial damages created in quasi isotopic laminated composites of the AS4/3501-6 graphite/epoxy system and ball bearing of the type 6204 with a steel cage. The Naïve-Bayes classifier and the proposed feature subset selection algorithm have been shown as efficient techniques for damage detection in engineering materials

Nonlinear finite element analysis of axially crushed cotton fibre composite corrugated tubes

It is proven experimentally that introducing corrugation along a shell generator together with a proper advanced composite material will enhance the crashworthiness performance of energy device units. This is because corrugation along the shell generator will force the initial crushing to occur at a predetermined region along the tube generator. On the other hand, a proper composite material offers vast potential for optimally tailoring a design to meet crashworthiness performance requirements. In this paper, the energy absorption characteristics of cotton fibre/propylene corrugated tubes are numerically studied. Finite element simulation using ABAQUS/Explicit was carried out to examine the effects of parametric modifications on the tube’s energy absorption capability. Results showed that the tube’s energy absorption capability was affected significantly by varying the number of corrugation and aspect ratios. It is found that as the number of corrugations increases, the amount of absorbed energy significantly increases

On the effects of geometrical shapes in failure modes in natural – conventional fiber reinforced composite tube: a review

Background: Natural and synthetic fibers are known for their low density, easier fabrication than metallic in several engineering applications. Furthermore, their structural rigidity is high and they can be used for advanced applications, such as aerospace applications and automotive industry sector. Methods: Owing to this in depth, studies had been conducted to evaluate its failure modes and process of fabrication for axial and lateral crushing behaviour to replace metallic materials. In this review paper, failure modes and geometrical designs such as shapes, triggering and geometry have been examined, where these factors are affected on crashworthiness parameters. The main aim of this review article is the reported work done in crushing behavior and failure modes of natural, synthetic and manufacturing technique process parameters on fibers reinforced composite tubes. Results: The results showed that the failure modes and crushing behavior in composite tubes depend on the type of material reinforced composite tubes and structure. Conclusion: The failure modes and crushing behavior in composite tubes depend on the type of material reinforced composite tubes and structure