الفهرس 
1.2 Classification of Composite MaterialOnly 14 pages are availabe for public view
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Abstract
Composite materials have interesting properties such as high strength to weight ratio and relatively high damping characteristics compared to metals which make them very attractive for rotating systems. They also provide designers with the possibility of obtaining the predetermined behaviors in terms of position of critical speed of rotating parts by changing the arrangement of the different composite layers orientation and number of piles. Composite materials now occupy an established position in the aerospace industry. They are also used for many components in the automotive industry and civil infrastructures now have their reinforcements made of composite materials. There is a large range of manufacturing processes for the production of low-cost composites. The application of composite shafts has come a long way from early lowspeed automotive drive shafts to helicopter tail rotors operating above the second critical speed. With operation at supercritical speeds, a substantial amount of payoffs and net system weight reductions are possible. At the same time, the rotor dynamic aspects assume more importance, and detailed analysis is required. There are some technological problems associated with implementation, such as joints with bearings, affixing of lumped masses, couplings, provision of external damping, and so forth. The solutions proposed are just adequate, but require substantial refinements, which might explain some of the differing experiences of various authors. Rotating machinery is widely used in industry. The dynamic analysis and active vibration control of the rotating machinery are important engineering problems for both industry and academia. In this work, a review of the research done in real-time active vibration control for rotating machinery, as well as the dynamic modeling and analysis techniques of rotor systems are presented The composite rotating shafts used will be fabricated using hand layout technique by filament winding technique. Glass fiber (E-Glass) as reinforced with a matrix of polyester resin and hardener will be used to construct the composite layers needed. Four cases will be studied using composite shafts fabricated by different layers of composite materials namely; different stacking sequence, fiber orientation angles, (L/D) ratio and finally various types of fiber volume fraction. Glass fiber is used as reinforcement in the form of bidirectional fabric
(Standard E-Glass Fiberglass) and polyester with catalyst addition as matrix for the composite material. The mechanical properties of the composite are calculated analytically using the mixture rule. The present work includes theoretical and experimental investigations of the dynamic analysis of a rotating composite shaft. The numerical finite element technique is utilized to compute the eigen pairs of laminated composite shafts. A finite element model (FEM) has been developed to formulate the stiffness matrices using lamination theory. These matrices take into account the effects of axial, flexural and rotating on the eigen-nature of rotating composite shaft. The Campbell diagram is utilized to compute the critical speed of rotating composite shaft and instability regions to achieve accuracy and for controlling the dynamic behavior of the system in resonance state. The influence of laminate parameters: stacking sequences, fiber orientation, boundary conditions and fiber volume fractions effect on natural frequencies and instability thresholds of the shaft are studied. The results are compared to those obtained by using the finite element method and experimental measurements using frequency response function method (FRF) by applying the autogenously excitation ”from self excitation due to driving motor”. In the experimental part, the response of composite shaft with various types of boundary conditions and five lamina orientations were recorded and analyzed.