A Synthetical Numerical Model for Evaluating the Reliability of Turbine Blade

Reliability of turbines is very important for power plants, and the most common blade failure normally result from forced vibration which lead to fatigue failure of blades. In this study, a synthetical numerical model has been developed to obtain more precise evaluation of the reliability of blades. At first, the model used to analyze the dynamic stress of steam turbine blades is investigated, base on the results of dynamic stress analysis, a model to evaluate the fatigue life of turbine blade has been developed, many factors such as manufacturing technology of blades and erosion operating environment are considered to get more accurate results for the fatigue life prediction of blades. At last, a 323 mm blade in a 75MW steam turbine is analyzed by the model developed in this paper, it is shown clearly that the model can provide some significant data to evaluate the reliability of blade.