Creep Analysis of High Temperature Components Under Multi-Axial Loading
A simplified solution method that enables the estimation of stresses and strains in high temperature components under creep conditions is presented. The solution is derived based on strain energy density considerations and is applicable to both uniaxial and multiaxial stress states. In particular, this simplified method is developed for an efficient estimation of the cyclic stress-strain history at critical locations which needed for fatigue analysis of hot sections under creep conditions where conventional finite element creep analysis becomes extremely time consuming. The input data necessary to perform this simplified solution are the stresses and strains obtained from a linear elastic analyses. If the finite element method (FEM) is used for the linear elastic analysis of components, then the simplified solution method can be programmed as a post processor file. The file uses the linear elastic FEM results and generates an approximate time-dependent analysis. Presented results illustrates the accuracy of the method by comparing with finite element creep analysis results for several hot sections under creep conditions. Also, it is shown that the computational time needed to perform this solution is far less than the conventional finite element creep analysis.