Fatigue and Crack Propagation Analysis of a 11000 Shp Turboprop Engine Front Bearing Structure and Validation

Abstract

All the components on a gas turbine should meet the requirements defined by the responsible associations. The front bearing structure which is assigned to be on the main load path of the engine has low cycle fatigue requirement to assure the integrity. Any invisible flaws or defects on the surface can cause cracks on the part. In this thesis, subjected component is investigated in the means of crack initiation and crack growth by the help of finite element method (FEM). Static structural FE analyses are completed prior to life calculations. Life number of cycles required to reach the failing limit is evaluated. A crack is introduced into FE model to find the crack growth rate. J-integral which is accepted as a fracture criteria and stress intensity factors are evaluated with respect to various defined crack lengths. Crack growth on the component is validated via LCF test. The finite element study delivered with ANSYS & ANSYS WB v16.0 and test results are compared in the study.