Prediction Of Progressive Damage And Failure Analysis Of Rotorcraft Composite Nose Cowling By Continuum Damage Mechanics Model

Abstract

The prediction of mechanical behaviour in composite structures can replace some of the mechanical tests and can significantly reduce the cost of designing with composites by exploiting advanced analytical or numerical models to achieve an optimized design. The present paper is concerned with the prediction of progressive damage which accumulates in sandwich laminates with polymeric matrix materials. The study is based on a continuum damage mechanics model which is implemented within the Finite Element Method (FEM). The failure mechanisms occurring in the longitudinal and transverse directions of a ply are represented by a set of scalar damage variables. Different failure mechanisms occurring at the ply level by using damage activation functions based on the Hashin failure criteria are used to predict ply damage. The practically important problem of rotorcraft nose cowling is attempted using Continuum Damage Mechanics (CDM) model as a design tool for the prediction of damaged behavior under service conditions.