New Method for Damage Tolerance Analysis of Turbine Disk and its Application

A new method for damage tolerance analysis of three dimensional component under temperature and centrifugal loads is proposed in this paper.First,stress intensity factors of three dimensional cracks on a pin hole of a turbine disk under temperature and centrifugal loads can be analyzed by use of the new type of dual boundary element method.Then incremental Euler forward analysis can be made to determine the shape of crack and crack growth life of the turbine disk step by step, with the help of Paris's formula of crack growth,until the maximum effective range of SIF of the 3 D crack reaches.Next,a second order estimation of crack growth life can be obtained by the trapezoid formula integration through the curve of crack length versus effective range of SIF.By virtue of the new type of dual boundary element method,influences of pin loads,temperature fields and shapes of cracks on stress intensity factors are analyzed.The crack growth life of a turbine disk is obtained using the method given in this paper afterwards.Approximation of an engineering method used before to calculate stress intensity factors of a crack near pin hole of a turbine disk is discussed too.Examples given in the paper demonstrate the high efficiency and easily modeling of three dimensional analysis of crack growth under complex loads by the present method.