The Influence of Different Arrangements of Steam Cooler on Steam Turbine Thermal Efficiency

For a reheat-regenerative cycle steam turbine, the increased superheat of extraction steam after reheating causes the regenerative effect to weaken. Steam cooler can make rational use of the superheat of the extraction steam to improve the thermal efficiency of steam turbine. Based on the heat balance calculation of steam turbine, the mathematical models of the influence of steam cooler on steam turbine thermal efficiency was established. With the models, calculated the influence of external series steam cooler and external parallel steam cooler on thermal efficiency. The calculation result shows that the thermal efficiency of the cycle with external steam cooler is higher than the cycle with integral type, and in the case of reasonable design, the efficiency of the cycle with external parallel steam cooler is higher than the cycle with series type. The analysis provides a theoretical basis for the optimization and remolding of the regenerative system.