ONR N0014-17-12040 – Multiscale Modeling of Composites Subjected to Fatigue Loading

Overview

The overall goals of this research are to establish a multiscale computational framework for the prediction of long-term performance of aerospace composites, and to gain fundamental understanding of the interactions between failure mechanisms under cyclic loading. In order to achieve this goal, the specific objectives of the program are:

  • Devise an efficient and accurate space-time multiscale computational framework for fatigue life prediction of composites, that achieves stable and mesh-independent damage propagation modeling, and also accounts for the interactions between all relevant damage mechanisms throughout the loading process (Lead: Prof. Caglar Oskay);
  • Establish and model the interlaminar degradation and fracture propagation mechanisms under fatigue loading, with particular emphasis on stability and accuracy of the underlying finite element formulation of cohesive zone models (Lead: Prof. Ravindra Duddu);
  • Gain a fundamental understanding of the interactions between damage modes under fatigue, which includes performing experimentally-validated numerical simulations, detailed analysis of the coupling between delamination, matrix cracking and fiber fracture, and characterization of the effects of damage interactions on the overall fatigue life (Lead: Prof. Caglar Oskay).

Publications

G. Ghosh, R. Duddu and C. Annavarapu, A stabilized finite element method for enforcing stiff anisotropic cohesive laws using interface elements, Computer Methods in Applied Mechanics and Engineering, 348: 1013-1038, 2019, doi: 10.1016/j.cma.2019.02.007 (link)

G. Ghosh, C. Annavarapu, R. Duddu, “A stabilized finite element formulation remedying traction oscillations in cohesive interface elements” Proceedings of the American Society for Composites: Thirty-third Technical Conference, pp. 14,  University of Washington, Seattle, Washington, September 24–26, 2018 pdf

G. Ghosh, C. Annavarapu, S. Jimenez, R. Duddu, “A stabilized finite element method for modeling mixed-mode delamination of composites” Proceedings of the American Society for Composites: Thirty-Second Technical Conference, pp. 16, Purdue University, West Lafayette, Indiana, October 23–25, 2017, doi: 10.12783/asc2017/15360 pdf

G. Ghosh, X. Sun, R. Duddu, “On the accurate recovery of crack surface traction in delamination analysis using cohesive zone models” Journal of Engineering Mechanics. to be submitted.

Students

Gourab Ghosh

Ph. D. student, Expected Graduation: December 2019

Research project: Stabilized finite element method for enforcing stiff cohesive laws to simulate static and fatigue delamination. 

Stephen Jimenez

Ph. D., Graduated: December 2017

Research project: Parametrically insensitivity cycle-based fatigue delamination models