Crack propagation in gas turbine rotor disks - Comparison of experimental results at real components with fatigue life prediction

摘要

Rotor disks of gas turbines are high stressed components and for safe life design both stress criteria and fracture mechanics are needed. Due to the forging process in rotor disks flaws have to be considered. There exists a certain detection limit, beneath no flaw size is detectable. A comparison of predicted and observed crack propagation in a real gas turbine rotor disk with machined surface cracks is presented. The comparision of experimental crack growth behaviour and life prediction shows that the fracture mechanics analysis is conservative and that non detectable flaws within gas turbine rotor components cannot hurt safe service operation.