Numerical Study to Valve Control Scheme of 660MW Supercritical Steam Turbine Based on SPE

As the parameters of the thermal power plant and the frequency of peak load operation rising continuously, Solid Particle Erosion (SPE) of steam turbine is getting more and more serious. Solid particle erosion leads to the damage of the steam turbine blade and the degradation of the turbine's performance. Taking a 660MW supercritical steam turbine, the numerical simulation is carried out aiming to get the impact density of SPE to the blades of the turbine's governing stage as its load varying respectively correspond to sliding pressure and constant pressure running modes. The influence of SPE with different valve control schemes are compared while the pressure keeping constant. The solid particle erosion of the steam turbine governing stage mainly occurs in the blades. As the load decreases during the sliding pressure operation, the erosion of the solid particles in the governing stage gradually increases. At high load, the valve control scheme has less effect on solid particle erosion and low load larger. Based on the analysis of the simulation results, a series of valve control scheme to reduce the SPE of governing stage are presented.