Fatigue Life Prediction of a Turbine Disc with Stress Gradient

Abstract

In this paper, a three-dimensional turbine disc model is established. By using the FEM (finite element method), the critical stress and strain concentration regions are determined according to the static structural analysis results of the turbine disc. Besides, the stress gradient distributions of the assembly holes, the gear teeth region, and the hub region are identified. Then by introducing an improved SWT (Smith-Watson-Topper) parameter model which can take the stress gradient effect into consideration, the fatigue life of the hub region, the gear teeth region, and the assembly holes is obtained. Comparing the life prediction results of the critical regions, finally we get the turbine disc’s fatigue life.