THE EFFECT OF CHANGE IN THE NUMBER OF STATOR BLADES IN THE STAGE ON UNSTEADY ROTOR BLADE FORCES

摘要

Analysed here was a 100-MW steam turbine in which the unsteady forces acting on the extraction stage rotor blades were found to be large. This was in particular valid for the circumferential components unsteady forces. Results of calculations performed for the same boundary conditions but with different numbers of stator blades in the system are presented. Increasing the number of stator blades considerably affects the level of unsteady forces acting on a single blade. These changes refer to both the stationary components of these forces and their first high-frequency harmonic, which decreases when the number of stator blades is increased.