Innovative Approaches for Improving Progressive Damage Modeling and Structural Life Prediction of Airframes

The stated objective of this SBIR effort is to"develop and demonstrate an innovative tool to prognosticate crack growth that integrates a next generation crack growth model with a robust finite element code."To achieve this objective, TDA envisions the development of a comprehensive toolkit that integrates the advanced crack growth model UNIGROW with the weight function technique and standard finite element packages. This toolkit will be capable of automated crack growth predictions for arbitrary crack shapes and geometries, and will serve as an expert system for growth simulation and risk analysis of multiple cracks in real structure by accounting for residual stress fields. With the above vision, and having successfully completed the Phase I effort, Phase II objectives are as follows: (a) improvements to UNIGROW modeling and weight function techniques for crack growth life prediction for several classes of spectrum loading; (b) full-featured integration of FEMAP and ANSYS with UNIGROW plus development of algorithms for enhanced capabilities; (c) continuing verification and validation of the UNIGROW package with published and Government furnished test data; (d) fielding a beta-version of the application and preparing for limited USN release for test and feedback.