Design Tools: Defect Criticality

Problem:

Assessing the affect of manufacturing or in-service defects on composite structures is critical. Current methods are subjective and rely heavily on engineering judgment.

Approach:

A suite of integrated finite element based software tools required development to assess specific defect types.

Solution:

Automated finite element based modelling tools were developed to represent impact damage (monolithic and sandwich), skin-stiffener separation, delaminations and fibre waviness. The tools were developed in the MSC.Patran environment (Patran Command Language) and utilised various FE solvers. The tools can be used to rapidly predict the change in stiffness and strength of a structure containing a particular damage or defect.

Outcome:

The developed tools enable the accurate assessment of composite components with manufacturing defects or in-service damage. The result is reduced scrap rates and more efficient repair processes. Repair rates are also reduced, by avoiding unnecessary repairs.