Lifing Analysis for First Stage Bladed-Disk of F-35B Aircraft Lift Fan

PITIPORNVIVAT, Maytwin

Objectives:

Outcomes/Results:

Thermal Power MSc, Aerospace Propulsion Option School of Engineering

Methodology:

Conclusions

September 2014

•  Investigate the acceptable service life cycles of the first stage bladed-disc Lift Fan regarding HCF, LCF, and crack propagation life applying safe-life lifing

•  Determine the proper inspection interval for the first stage bladed-disc by applying damage tolerance lifing

•  The component acquires infinite LCF life and can withstand HCF of up to 1.4x106 flight cycles with S.F. of 1.5

•  Based on material anomaly sizes, it is best to have the component inspected for cracks once in every 3,401 flight cycles

•  Achieved a feasible Lift Fan design with the overall efficiency of 0.867 delivering PR = 2.1

Supervisor: HASLAM A.

Key References •  AC33.14-1, “Damage Tolerance for High Energy Turbine Engine Rotors”, Federal Aviation Administration (FAA), U.S. Department of Transportation.

Flight Cycles S.F. HCF Life 20,000 or (1.4x106) 2.08 or (1.5) LCF Life Infinite N/A

Fracture Life 4,535 1.5 Inspection

Interval 3,401 N/A

•  Maximum stress in the bladed-disk of 230.26 MPa at TE of 25% blade span with acceptable static stress S.F. of 3.62

Comparison of inspection intervals for two phases of crack propagation with max./min. material anomaly size