An investigation of fatigue failures of turbine blades in a gas turbine engine by mechanical analysis

Abstract Blade failures in gas turbine engines often lead to loss of all downstream stages and can have a dramatic effect on the availability of the turbine engines. Thorough failure investigation is essential for the effective management of engine airworthiness. In this paper blade fatigue failures are investigated by mechanical analyses and by examination of failed blades. A series of mechanical analyses were performed to identify the possible causes of the failures by examining anomalies in the mechanical behaviour of the turbine blade. A non-linear finite element method was utilised to determine the steady-state stresses and dynamic characteristics of the turbine blade. The steady-state stresses and dynamic characteristics of the blade were evaluated and synthesised in order to identify the cause of blade failures.