An important characteristic of a steam power plant is its ability to maintain reliability and
safety of the plant against frequent start-ups and load changes. Transient regimes arising during
start-ups, shut-downs and load changes give rise to unsteady temperature distribution with time in
steam turbine rotor(HP/IP), which results in non-uniform strain and stress distribution. The rapid
increase of temperature and rotational speed during starts-ups, especially, makes conditions more
severe and causes main components’ damage and reduction of life span for steam turbine. Thus
accurate knowledge of thermal and centrifugal stresses are required for the integrity and lifetime
assessment for the turbine rotor. So far, only elastic calculations are currently performed for
simplicity. However, it is well known that the materials of steam turbine rotor deform inelastically
at high temperature. Existing models proposed to describe the viscoplastic(rate-dependent) behavior
are rather elaborate and difficult to incorporate with computer simulations in the case of complex
structures. In this paper, the life assessment for steam turbine rotor was established by combining
the inelastic behavior and the finite element method. The inelastic analysis was particularly focused
on viscoplastic behavior that is simple enough to be used effectively in computer simulation and
matches the essential features of the time-dependent inelastic behavior of materials reasonably well
for cyclic loading under non-isothermal conditions. Using this study, life consumption of steam
turbine rotor can be obtained.
A linear cascade tunnel for flow investigations of steam turbine rotor tip blades in subsonic nucleating flows
