Dynamic Analysis of Three-Dimensional Composite Tube Shafts
01 Jan 2021-pp 51-63
TL;DR: In this paper, the in-plane elastic properties at different fiber volume fractions of 3D composite tube shafts are obtained from the literature and modal analysis is carried out, and bending natural frequencies are calculated for different 3D composites with E-glass, carbon and kevlar fibers and epoxy as matrix materials.
Abstract: Three-dimensional (3D) composites have good delamination resistance along with high specific stiffness and high specific strength. Composite tube shafts are modeled with different reinforcement architecture such as multi-axial, stitched, knitted, braided, orthogonal woven, interlock and z-pinned. The in-plane elastic properties at different fiber volume fractions of these composites are obtained from the literature. 3D composite tube shafts are modeled with length: 1 m, internal radius: 25 mm and thickness: 4 mm using modified equivalent modulus beam theory formulation. Modal analysis is carried out, and bending natural frequencies are calculated for different 3D composite tube shafts with E-glass, carbon and kevlar fibers and epoxy as matrix materials. The natural frequency reduces with through thickness reinforcement for orthogonal, knitted, z-pinned and stitched composites. Braided composites tube shafts have higher natural frequencies compared to that of other types.
References
More filters
TL;DR: In this paper, a critical review of multiaxis 3D woven preform structures and techniques is provided on the development of multi-dimensional (3D) woven preforms and techniques.
Abstract: The aim of this study is to review three-dimensional (3D) fabrics and a critical review is especially provided on the development of multiaxis 3D woven preform structures and techniques. 3D preforms are classified based on various parameters depending on the fiber sets, fiber orientation and interlacements, and micro–meso unit cells and macro geometry. Biaxial and triaxial two-dimensional (2D) fabrics have been widely used as structural composite parts in various technical areas. However, they suffer delamination between their layers due to the lack of fibers. 3D woven fabrics have multiple layers and no delamination due to the presence of Z-fibers. However, the 3D woven fabrics have low in-plane properties. Multiaxis 3D knitted fabrics have no delamination and their in-plane properties are enhanced due to the bias yarn layers. However, they have limitations regarding multiple layering and layer sequences. Multiaxis 3D woven fabrics have multiple layers and no delamination due to Z-fibers and in-plane properties enhanced due to the bias yarn layers. Also, the layer sequence can be arranged based on end-use requirements. However, the multiaxis 3D weaving technique is at an early stage of development and needs to be fully automated. This will be a future technological challenge in the area of multiaxis 3D weaving.
129 citations
TL;DR: In this article, the mechanical properties of z-pinned composite laminates were examined numerically and a micro-mechanical finite element model was employed to understand how the through-thickness reinforcement modifies the engineering elastic constants and local stress distributions.
Abstract: The mechanical properties of z-pinned composite laminates were examined numerically. Finite element calculations have been performed to understand how the through-thickness reinforcement modifies the engineering elastic constants and local stress distributions. Solutions were found for four basic laminate stacking sequences, all having two percent volume fraction of z-fibres. For the stiffness analysis, a micro-mechanical finite element model was employed that was based on the actual geometric configuration of a z-pinned composite unit cell. The numerical results agreed very well with some published solutions. It showed that by adding 2% volume fraction of z-fibres, the through-thickness Young's modulus was increased by 22–35%. The reductions in the in-plane moduli were contained within 7–10%. The stress analysis showed that interlaminar stress distributions near a laminate free edge were significantly affected when z-fibres were placed within a characteristic distance of one z-fibre diameter from the free edge. Local z-fibres carried significant amount of interlaminar normal and shear stresses.
102 citations
TL;DR: In this article, a review of currently developed micromechanical modeling techniques for predicting the stiffness and strength of knitted fabric composites is presented, and a comparative study of the predictive capabilities of various techniques is carried out based on a plain weft knitted glass fiber fabric reinforced epoxy matrix composite.
Abstract: Knitted fabric reinforced composites have been investigated widely in recent years. A number of different micromechanical modeling schemes have been proposed in the published literature for various types of knitted fabric composites. However, to date, no comparative study has been made to evaluate the suitability of different modeling schemes to predict the stiffness and strength properties of knitted fabric composites. This paper presents a review of currently developed micromechanical modeling techniques for predicting the stiffness and strength of knitted fabric composites. Further, a comparative study of the predictive capabilities of various techniques is carried out based on a plain weft knitted glass fiber fabric reinforced epoxy matrix composite. Useful conclusions are drawn based on the comparative study.
74 citations
TL;DR: In this article, a review of models for 3D woven fabrics in the dry state and results that were achieved with parametric studies is presented. But the authors focus on the determination of the initial configuration of the 3D yarn model.
74 citations
TL;DR: In this article, the natural frequencies of composite tubular shafts have been analyzed using equivalent modulus beam theory (EMBT) with shear deformation, rotary inertia and gyroscopic effects.
67 citations