The turbine plant efficiency: Maximum efficiency attained and the share of individual stages

A feasible version of an equation relating the turbine plant (either steam or gas) efficiency to the kinetic energy of the gas/steam flow is presented: ηi=∑1nφj×[ηmaxΔPi(ΔP0+ΔPi)]j, where ηi is the turbine plant efficiency in an i-state (Ti, Pi); ΔPi is the kinetic energy of the moving flow converted into work; ΔP0 is the minimum consumption of the gas (steam) kinetic energy necessary to make the turbine rotate by overcoming the rest inertia; ηmax is the maximum efficiency attainable at the given turbine plant; φj is a definite share that the individual stage is adding to the efficiency of a turbine plant; n is the number of stages in the turbine plant. As the derived equation is applicable both to the turbine plant as a whole and to its individual stages, there is an opportunity to estimate their contribution to the efficiency of the entire turbine plant. Using abovesaid equation in processing experimental data facilitates estimation of a maximum efficiency attained, as well as the consumption of the kinetic energy of the gas flow to overcome the inertia forces. The equation makes possible functional monitoring of an operating turbine plant, which can be useful in upgrading and optimizing individual units or designing new turbines.