Identification of Water Erosion-prone Areas in High-back-pressure Steam Turbines under Typical Operating Conditions Using Empirical Formula and Streamline Analysis

Water erosion of final-stage rotor blades is a critical issue for high back-pressure heating steam turbines, especially under variable-load operation. In this study, a ۳۰۰ MW high back-pressure heating steam turbine was investigated, and the relative erosion risk of the final-stage rotor blades was evaluated by combining an empirical erosion coefficient with streamline analysis under typical load and back-pressure conditions. The results indicate that, for the original blade configuration, the main erosion-prone region is located at approximately ۷۰% blade height under medium- and high-load conditions. When the load decreases to ultra-low levels, the high-risk region shifts toward the blade root and is mainly distributed within ۳۰%–۵۰% blade height. After removal of the last two stages, the predicted erosion risk is relatively low under medium- and high-load conditions, while slight erosion risk appears below ۳۰% blade height under ultra-low-load operation. This study provides a practical method for identifying water erosion-prone areas and supporting targeted inspection and maintenance.

کلیدواژه ها:

Typical operating conditions ، Final stage blade ، High back-pressure heating steam turbine ، Low-pressure cylinder ، Water erosion-prone areas