Study on the Impact to the Equivalent Enthalpy Drop Model with Exhaust Enthalpy Inaccuracy

摘要

The equivalent enthalpy drop method is an effective tool in the analysis of thermodynamic system, but in the calculating process of equivalent enthalpy drop method, the steam turbine exhaust enthalpy needs determining in advance. For condensing turbine, the exhaust steam condition point is usually in the wet vapor region, and exhaust enthalpy can't be confirmed exactly for condenser steam turbine, so the results of the equivalent enthalpy drop method have the certain computational inaccuracy. Based on the basic principle of thermal system, the inaccuracy of model is presented when some parameter of regenerative system changes. Then, the examples that valve lever leakage increasing and heater terminal difference are illustrated by a steam turbine of a 200MW power plant, calculation is done about exhaust enthalpy inaccuracy affecting on calculation result.