Analysis of Interlaminar Damages in Thick Rotorcraft Composite Components by Embedded Sensors

The present study is focused on embedding piezoelectric transducers in thick laminated rotorcraft composite components for the purpose of monitoring interlaminar damage initiation and growth. The objective is to develop and demonstrate modeling capabilities to predict piezoelectric sensor output in complex composite components with and without damages. Additional goal is to demonstrate sufficient sensitivity of the predictions for different scenarios (sizes, locations) of typical damages, primarily in rotorcraft applications. Computational implementation of the modeling capabilities is demonstrated using FEA code ABAQUS and ultrasonic testing (UT) simulation code CIVA. Advantages and limitations of the implementations are discussed in detail. The analysis is illustrated on example of a thick composite coupon with complex tapered lay-up with numerous ply-end areas. A systematic parametric analysis is performed to understand and quantify predictions with respect to locations and sizes of considered damages. Generated results can be used for optimization of piezoelectric sensor based monitoring techniques and better general understanding of damage and piezoelectric sensor output correlations in rotorcraft composite components..