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Abstract

Design requirements of turbine rotors capable of performing cyclic operations demand the need of both brittle and ductile fracture analyses. This paper presents a method of brittle analysis in turbine rotors. In another paper the author has dealt with the problem of ductile analysis. Generalized equations for different types of defect configurations commonly observed in defective rotors are formulated and discussed in terms of the computed average bursting strength and fatigue life. The computer results are presented in graphical form to facilitate design procedures and acceptance standards. A design criterion concerning the necessity of bore-holes in turbine rotors is proposed. It is intended to improve the present practice of indiscriminate use of costly rotor boring processes. The brittle fracture analysis devised is applied to a marine turbine rotor during its typical cold start and the results computed are found to be satisfactory.

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Method of Brittle Fracture Analysis in Turbine Rotors during Cold Starts

Abstract

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