Abstract
Based on the mode III stress intensity factor, three kinds of crack and their influence on rotor's torsional shear stress are studied in this paper. By deducing and calculating the stress intensity factor K_<IIIA> both for the transverse straight crack model and the transverse semi-elliptical crack model, and for the transverse straight crack model and the slant crack model, relationships between K_<IIIA> and a/R for these models are obtained. Then, W_e (the relative difference concerning torsional shear stress of the transverse straight crack model and the transverse semi-elliptical crack model) and W_<sl> (the relative difference concerning torsional shear stress of the transverse straight crack model and the slant crack model) are defined. In addition, the relationship between a/R and (a/c)_<cr> and the relationship between W_<sl cr> and θ_<cr> are obtained. They are very useful for engineering applications when simplicity is needed.
