General Calculation Formula on the Influence of Extraction Steam Pressure Loss on Thermal Economy of Unit

Extraction steam pressure loss will occur as extraction steam flows through the pipe and the heater. The thermal economy of the unit is decreased by the occurrence of extraction steam pressure loss. Based on the basic equations of thermodynamic system, the influence of drain water enthalpy on thermal efficiency of unit is calculated in the paper, and the law of formulas is found. It is proved by the paper work that the influence of extraction steam pressure loss on thermal economy is actually the superposition of the influence of heater outlet water enthalpy and drain water enthalpy on thermal economy. Based on the paper work, the influence of extraction steam pressure loss on thermal economy of unit is built. The method discussed in the paper is not only prone to be used, but suitable for computer program. The method possesses the universal property. The general calculation formula is proved to be right by an application example.