Reliability Prediction of a Return Thermal Expansion Joint

An efficient reliability assessment approach is used to estimate the reliability of a return expansion joint. This component is part of a large power generation system. In order to perform the reliability assessment task, Computational Fluid Dynamics (CFD), Finite Element Method (FEM), Fatigue analysis, and Monte Carlo Simulation (MCS) tools are integrated. The process starts with CFD simulation to determine the convective terms necessary for the transient FEM thermal analysis. The thermal analysis provides maximum thermal stress whereby the fatigue life of the component is estimated. As a result of input parameters uncertainty, the calculated life is in the form of a Probability Density Function (PDF), which enables the calculation of the reliability of the component. The application of this reliability prediction procedure to the return expansion joint can be used to enhance the design and operation of the component by uncovering under-design or over-design. Under-design warrants further studies using the same method to determine how to enhance the reliability. On the other hand, over-design can be eliminated to reduce the manufacturing cost of the component. Furthermore, various alternative designs and operational scenarios can be studies using this model.