Creep analysis of rotating solid disks with variable thickness and temperature

Abstract

A creep analysis for stress distributions in rotating solid disks of variable thickness and variable temperature is presented. This analysis is based on the theory of the Tresca criterion and the associated flow rule. The chief advantage of this analysis for stress distribution is that the complicated problem of disk design in gas turbines and jet engines can be solved with great simplicity by the closed form. The results obtained for the disk design will be on the conservative side. In this paper, the exponential function creep law at steady-state conditions will be employed. The profile of the meridian section of the disk is assumed to be of the hyperbolic form, and the temperature variation and the creep-rate distribution are assumed to be power functions of the radius of the disk. Some examples will be worked out for calculating the theoretical stress distributions in variable thickness and variable temperature disks. Stress distributions in uniform-thickness and variable-temperature disks will also be given for the purpose of comparison.