Off-Design Performance Analysis of a 7 MW Class Steam Turbine by Streamline Curvature Method

Steam turbines have been used for various applications such as electric power generation or an engine for transportation since the 19th century. However, the published data for the performance analysis are very limited due to the exclusive policy among leading manufacturers. Therefore, in this study, a study was conducted for performance analysis of steam turbine. The streamline curvature method was developed and it was validated on a used steam turbine. The compared results showed that they were quite well agreed with existing results. In addition, it was applied to a designed 7 MW class steam turbine of ten stages for obtaining the performance at off-design points. The comparable result at design point was well agreed, and the performance at off-design points showed that the output power of the turbine was quite sensitive for the varied temperature at turbine inlet. The output power was decreased by 13% for a 10% decrease of temperature at inlet. The turbine was operated in the wetted state except a few stages of high pressure to obtain the higher output power.