Theoretical and Numerical Analysis of the Mechanical Erosion in Steam Turbine Blades. Part II

Abstract

In the low pressure section of the steam turbines the damages are pronounced becoming remarkable in all the stages, since the generation of water liquid microparticles implies the impact on the blades having majors problems of erosion in the last stages by the increase of the humidity. In the first part of this work, the calculation presented of the transonic velocity field for the stream frictionless and the drops in the flow line, on the basis of the frictionless, two-dimensional, stationary, transonic and homogenous flow, give an approximate movement of the droplets and its accumulation on the stator blades, flowing through the steam. In order to understand the causes that originate the erosion on the blades of the last stages in low pressure section of steam turbines, the previous procedure is developed in a code in Fortran and the obtained results of velocity distribution in the output of blades that have flow conditions of wet steam are presented.