Reliability Analysis of LCF Life for a Turbine Disk
Cyclic stress-strain curve and cyclic strain-life curve appear distinct scatters, and the scatter of fatigue life increases with reducing of the strain levels. A methodology for reliability simulation of low cycle fatigue (LCF) life for turbine disk structures is developed in this paper. First, probabilistic cyclic stress-strain model and linear heteroscedastic probabilistic cyclic strain-life model are founded based on the fatigue test data. Second, three dimensional model of a turbine disk is built, and the fatigue reliability analysis of this turbine disk is implemented in probabilistic design module (PDS) of ANSYS by the combination of response surface method (RSM) and Monte Carlo simulation (MCS). The predicted life with reliability 0.9987 is well consistent with the technology life obtained from disks LCF tests by scatter factors method.
Sihai Jiao, Zhengyi Jiang and Jinglong Bu
Y. Gao et al., "Reliability Analysis of LCF Life for a Turbine Disk", Advanced Materials Research, Vols. 146-147, pp. 1379-1385, 2011