Nonlinear fracture resistance parameters for cracked aircraft GTE compressor disk

Abstract

This study is concerned with numerical analysis of cracked aircraft gas turbine engine (GTE) compressor disk based on plastic stress intensity factor (SIF) approach. Damage accumulation and growth at operation have occurred in slot fillet of disk and blade attachment. In all of these failures, crack propagation started from part-trough quarter elliptical corner surface flows. In order to determine elastic-plastic fracture resistance parameters full-size stress-strain state analysis of compressor disk was performed for a quarter elliptical surface cracks under operation loading conditions. The process of numerical calculations includes the analysis of the elastic constraint parameters in the form of the non-singular T-stress and TZ –factor, as well as the elastic-plastic constraint parameters in the form of the local stress triaxiality h and In-factors for the various crack sizes and different operation temperatures. The plastic SIF Kp, which is shown to be sensitive to the constraint effects and environmental conditions, offers an attractive option as a self-dependent, unified parameter for use in characterizing the fracture resistance for a variety of aircraft GTE rotating components.