Failure analysis of an aircraft GTE compressor disk on the base of imitation modeling principles

Abstract This study is concerned with failure analysis of an aircraft gas turbine engine (GTE) compressor disk made from titanium alloy on the base of imitation modeling principles. The failures have occurred by part-through surface cracks in a disk and blade “dovetail type” attachment. On the base of this attachment dimensions the two geometries of imitation models of GTE compressor disk are developed. The loading conditions of the imitation models are found and numerically verified to reproduce the loading conditions in the compressor disk at operation. The comparisons of stress-strain state at critical zones of compressor disk and imitation models are presented. Experimental fixtures are designed to reproduce operation loading conditions in compressor disk during the tests on a servo-hydraulic test system. It is demonstrated that proposed imitation modeling principles allow estimating residual life of compressor disk with taking into account crack initiation and growth at critical zones. The possibility of using experimental imitation modeling for calibration of the theoretical crack growth rate model including the fracture process zone sizes and nonlinear fracture resistance parameters is considered.