ON EFFICIENCY MEASUREMENTS FOR LARGE STEAM-TURBINE LOW-PRESSURE STAGES

Current trends in the development of power engineering are turning att ention towards modernization of the machinery and equipment. Moderniza tion of the LP (low-pressure) part of a turbine is one of the most pro mising solutions. A natural question which arises concerns the effecti veness of such modernization, i.e. a comparison of the characteristics (efficiency) of this turbine part before and after modernization. Suc h a comparison may be based on measurements of the efficiency of the L P part and the last stage before and after the modernization, provided that the efficiency gain achieved exceeds the measuring error. This p aper deals with the estimation of the accuracy of such a measurement, the principle and methodology of which have been developed at the Inst itute of Fluid-Flow Machinery (IFFM) for a real turbine.