Study on Thermal Coupling Characteristics of Constrained Blades Based on Spin Softening

Abstract

The effects of spin softening and thermal shock had important influence upon the structural stability of blades in rotary machinery. Based on the theories of rotor dynamics and thermodynamics, a dynamic model of rotating blade was built. Considering the effect of spin softening, the research on vibration characteristics of high speed rotating blades was carried out under the centrifugal field and thermal coupling. The results had demonstrated that frequency of blade vibration increases with rising rotating velocity due to the effect of centrifugal force, whilst the frequency of all orders declined with the influence of thermal coupling. The conclusion derived from this paper had both theoretical and empirical value on retrofitting, optimal-designing, as well as engineering application for high speed rotating blades