Author:
Iyer Nagesh R.,Murthy A. Rama Chandra,Rajasankar J.,Palani G.S.
Abstract
This paper presents the details of damage tolerance evaluation of a Wing Bottom Skin Panel (WBSP) of an aircraft. Finite element analysis (FEA) of an integrally stiffened WBSP has been conducted to identify the probable location for crack initiation and the same has been confirmed by conducting experiments. Linear elastic fracture mechanics (LEFM) principles have been used for computation of stress intensity factor (SIF). Static results obtained from FEA and experiments are found to compare well. SIF has been computed for different crack lengths in mode I under intact-stiffener condition by using displacement extrapolation and strain energy release rate (SERR) techniques. SIF has also been computed for the same crack lengths under broken stiffener and unstiffened conditions. A comparison between the residual strength predicted under intact-stiffener, broken stiffener and unstiffened conditions clearly indicates the efficacy of the stiffener in arresting the crack propagation.
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