The turbine blade root is found to contain a surface fatigue crack of 3.3 mm during a routine maintenance inspection. The major stop-start load cycle is experienced twice per day with a minimum stress of 34 MPa and a maximum stress of 195 MPa. The turbine blade has a KIC of 75 MPa√m. Fatigue crack growth rate data for this alloy is given by: the Paris law constant, A = 4.5 x 10-11 and the Paris law exponent, m = 3.8. How many more stop-starts would you recommend be used? Explain your reasoning. You can assume the shape factor Q = 1.2, K is in MPa√m and a (crack length) is in m

The turbine blade root is found to contain a surface fatigue crack of 3.3 mm during a routine maintenance inspection. The major stop-start load cycle is experienced twice per day with a minimum stress of 34 MPa and a maximum stress of 195 MPa. The turbine blade has a KIC of 75 MPa√m. Fatigue crack growth rate data for this alloy is given by: the Paris law constant, A = 4.5 x 10-11 and the Paris law exponent, m = 3.8. How many more stop-starts would you recommend be used? Explain your reasoning. You can assume the shape factor Q = 1.2, K is in MPa√m and a (crack length) is in m

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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