Patching Efficiency in Cracked Aircraft Structural Panels Repaired with Bonded Piezoelectric Patches

Abstract

In this paper, the patching efficiency in cracked aircraft structural panels repaired with single-sided and double-sided piezoelectric patches is investigated. A two-dimensional finite element method is used to obtain the patching efficiency which has relation to stress intensity factors at a crack tip. The aircraft structural panel and piezoelectric patch are modeled as layers composed of Mindlin plate elements, and the stress intensity factors are calculated using the modified crack closure method. By performing numerical analysis, the effect of location of an active piezoelectric actuator on the patching efficiency is examined in the case of a single-sided piezoelectric patch. Moreover, the optimization of electric fields applied to piezoelectric actuators for maximizing the patching efficiency is conducted. In the case of double-sided piezoelectric patches, we also perform the numerical analysis of the patching efficiency, and finally demonstrate experimentally the enhancement of patching efficiency due to the activation of piezoelectric actuators as a step toward the practical use of piezoelectric patches.