20 May 2011
20 May 2011
Stanford University are engineering a new 2-ply angle composite laminate structure to reduce the weight and cost of composite laminates with the help of simulations done with MSC Nastran.
The 2-angle building block is being engineered at the Stanford University with the goal of increasing strength and durability by suppressing matrix cracking and offsetting deformation from shear coupling associated with anisotropic layer.
The 4-angle balanced laminate has been the choice of designers for years because of its metal-like behaviour. Bi-angle laminates can have ply stresses engineered to work synergistically. A [0/25] beam has 39% less deflection and more than 30% higher first natural frequency than 4-angle quasi-isotropic laminates.
“Through simulations using MSC Nastran, we were able to implement our new approach to design composite structures. Instead of ply-by-ply modelling of a composite laminate, we tried using the smeared properties. We performed analysis and optimisation by using a homogenised anisotropic plate instead of the traditional ply-by-ply model. We discovered that as we increased the number of plies in the Finite Element Method (FEM) model, we were able to proportionally save time and effort,” said Dr. Melih Papila, Stanford University. “Since we envisioned that laminates will have at least 32 plies, we estimate that the use of simulation tools in MSC Nastran will allow us to increase our work rate by about 32 times.”
Professor Emeritus Stephen W. Tsai reiterated the importance of MSC Nastran by stating, “Sophisticated simulation features in MSC Nastran will not only help design the best structure, but will more than pay for itself over time, and ensure safety.” “The use of composites is growing at a rapid rate,” said Ken Welch, VP of Product Management at MSC Software. “MSC is pleased to see Stanford's reliance on MSC Nastran, and will continue supporting research and development initiatives aimed at improving the modelling and simulation of composite materials so product manufacturers can apply new and better design and development methods.”