The Steady-State Thermo-Mechanical Analysis of Turbine Rotor

Abstract

Circumferential rod-fastened rotor is one kind of extensively applied structures of gas turbines which work at high temperature to expand hot gas and generate power. The steady-state temperature distribution of the turbine rotor as well as the thermal deformation and stress state were calculated through a thermo-mechanical analysis. A cyclic model of a four-disc rod-fastened turbine rotor assembly was built. A thermal analysis was carried out to obtain the steady-state thermal map of the turbine rotor with the thermal boundary conditions calculated through heat transfer empirical correlations. A static structural analysis was performed to derive the deformation and stress field under both thermal and mechanical loads which incorporate both the pre-tightening force of the rods and the centrifugal force of the rotor itself. The thermo-mechanical results are compared to the result with only mechanical loads applied. The comparison shows the steady-state thermal loads have an influence on the stress state of the rotor and the deformation of the rods.