Main Article Content
Abstract
In multi-cell aircraft wing construction, cutouts and vent-holes are commonly provided in the wing spars and ribs to facilitate fuel transfer across cells. While the web of the spar is expected to transfer shear loads under an overall bending load, presence of such discontinuities are of great concern. In particular, wing spars made of fiber reinforced composites, such discontinuities may result in fiber terminations and are well known locations of stress concentration. Present work attempts to analyze a carbon fiber composite (CFC) wing spar, with cutouts and vent-holes, under fixed beam conditions with the load applied through the shear centre of the spar to induce a pure bending stress at the cutout, through FE analysis and with a limited number of experiments. The study includes C-spars with and without skin-strips made of carbon fiber composites, and the cutout loaded in, both, tension and compression. The strain data measured extensively during the tests was employed to identify stress concentrations, critical failure locations and failure modes. The study establishes the need for modeling the whole loading assembly to achieve results close to experimental results.
Keywords
Article Details
References
- Ghannadpour, S.A.M., Najafi, A. and Mohammadi, B., "On the Buckling Behavior of Cross Ply Laminated Composite Plates Due to Circular/elliptical Cutouts", Jl. Comp. Strs., No.75, 2006, pp.3-6.
- Rezaeepazhand, J. and Jafari, M., "Stress Analysis of Perforated Composite Plates", Jl. Comp. Strs., No.71, 2005, pp.463-468.
- Guo, S., "Stress Concentration and Buckling Behavior of Shear Loaded Composite Panels with Reinforced Cutouts", Jl. Comp. Strs., No.80, 2007, pp.1-9.
- Eiblmeier, J. and Loughlan, J., "The Buckling Response of Carbon Fibre Composite Panels with Reinforced Cutouts", Jl. Comp. Strs., No.32, 1995, pp.97-113.
- Eiblmeier, J. and Loughlan, J., "The Influence of Reinforcement Ring Width on the Buckling Response of Carbon Fibre Composite Panels with Circular Cutouts", Jl. Comp. Strs., No.38, 1997, pp.609-622.
- Guo, S., Morishima, R., Zhang, X. and Mills, A., "Cutout Shape and Reinforcement Design for Composite C-section Beams Under Shear Load", Jl. Comp. Strs., No.88, 2009, pp.179-187.
- Henshaw, J.M., Sorem, J.R. and Glaessgen, E.H., "Finite Element Analysis of Ply-by-Ply and Equivalent Stress Concentrations in composite plates with multiple Holes Under Tensile and Shear Loading, Jl. Comp. Strs., No.36, 1996, pp.45-48.
- Mahase H. and Whitworth, H.A., "Failure of Orthotropic Plates Containing a Circular Opening", Jl. Comp. Strs., No.46, 1999, pp.53-57.
- Robert M. Jones., "Mechanics of Composite Materials", Second Edition, 1999, Taylor and Francis Inc.
- Panbarasu, K., "Analysis of Perforated CFC Wing Spar", M. Tech Thesis, MVJ Engineering College, Bangalore, 2010.
References
Ghannadpour, S.A.M., Najafi, A. and Mohammadi, B., "On the Buckling Behavior of Cross Ply Laminated Composite Plates Due to Circular/elliptical Cutouts", Jl. Comp. Strs., No.75, 2006, pp.3-6.
Rezaeepazhand, J. and Jafari, M., "Stress Analysis of Perforated Composite Plates", Jl. Comp. Strs., No.71, 2005, pp.463-468.
Guo, S., "Stress Concentration and Buckling Behavior of Shear Loaded Composite Panels with Reinforced Cutouts", Jl. Comp. Strs., No.80, 2007, pp.1-9.
Eiblmeier, J. and Loughlan, J., "The Buckling Response of Carbon Fibre Composite Panels with Reinforced Cutouts", Jl. Comp. Strs., No.32, 1995, pp.97-113.
Eiblmeier, J. and Loughlan, J., "The Influence of Reinforcement Ring Width on the Buckling Response of Carbon Fibre Composite Panels with Circular Cutouts", Jl. Comp. Strs., No.38, 1997, pp.609-622.
Guo, S., Morishima, R., Zhang, X. and Mills, A., "Cutout Shape and Reinforcement Design for Composite C-section Beams Under Shear Load", Jl. Comp. Strs., No.88, 2009, pp.179-187.
Henshaw, J.M., Sorem, J.R. and Glaessgen, E.H., "Finite Element Analysis of Ply-by-Ply and Equivalent Stress Concentrations in composite plates with multiple Holes Under Tensile and Shear Loading, Jl. Comp. Strs., No.36, 1996, pp.45-48.
Mahase H. and Whitworth, H.A., "Failure of Orthotropic Plates Containing a Circular Opening", Jl. Comp. Strs., No.46, 1999, pp.53-57.
Robert M. Jones., "Mechanics of Composite Materials", Second Edition, 1999, Taylor and Francis Inc.
Panbarasu, K., "Analysis of Perforated CFC Wing Spar", M. Tech Thesis, MVJ Engineering College, Bangalore, 2010.