Optimization of start-up conditions to reduce thermal loads in cooled components of a supercritical steam turbine

The paper describes the analysis of a start-up process of supercritical steam turbines. The issue under investigation is the decrease of thermal loads due to the designs that are specific to this type of machine. The analysis focuses on the main components-the rotor and the inner casing which operate at the highest level of the thermal loads. The analysis involves determination of the temperature and the stress fields and behavior in response to transient loading (thermal elongations). The results obtained enable a comparison to be made of various cases of transient loading.