Micro/macro analysis of a composite Casa Day 22/11/06
Motivation Aloha Airlines Flight 243 Honolulu International Airport, Hawaii No visual exterior inspection (nor required) At 24000 feet… loud clap Flight attendant swept out of the cabin 1 dead, 65 injured $5 million damage
Peel Test Force Displacement (constant speed) Nickel layer 45º Substrate Peel-Test Support
Composites Inclusions Matrix
Elasticity problem for a composite material Inclusions Matrix Material Interface Matrix Inclusions
Modelling Inclusions Matrix Material Interface Matrix Inclusions
Homogenisation
Homogenisation
Homogenisation
Homogenised equations Boundary Conditions
Macro results
Micro/Macro
Domain decomposition
Dirichlet – Neumann scheme
Finite element approximation
Finite element approximation Schur complement system • symmetric • positive definite • ill conditioned
Algorithm Dirichlet problem Neumann Problem Relaxation step
Algorithm is a preconditioner for Theorem: This process converges if where is the maximum eigenvalue of .
Example Macro domain Reference solution Meso domain
Example Absolute error for the horizontal displacement u 1 -uref 0. 6012 u 2 -uref 0. 6701 u 3 -uref 0. 1392 u 4 -uref 0. 0305 u 5 -uref 0. 0176 Macro domain Meso domain
Future Work - Interface conditions discussion - Crack propagation