直接空冷凝汽器压力特性的耦合计算与分析方法

Coupling Calculation and Analysis Method of Direct air Condenser Pressure Characteristics

传统的空冷凝汽器特性计算方法中认为汽轮机低压缸排汽焓保持不变,但实际上空冷凝汽器压力的变化也会反向影响排汽焓,进一步对凝汽器压力产生耦合影响。基于空冷凝汽器背压与排汽焓的耦合分析,提出了一种基于迭代算法的空冷凝汽器模型与分析方法。通过对某600MW机组空冷凝汽器的计算分析,得出其在不同汽轮机负荷、环境温度工况下凝汽器压力的变化特性曲线,定量分析了汽轮机负荷和环境温度变化对凝汽器压力影响的对应关系,对空冷机组的安全经济运行具有一定的参考价值。

In the traditional calculation method of air condenser characteristics,it is considered that the exhaust enthalpy of the low pressure cylinder of the steam turbine remains constant,but the change of the actual overhead condenser pressure will also have a reverse effect on the exhaust enthalpy,and then have a coupling effect on the condenser pressure.In this paper,based on the coupled analysis of the back pressure of the air condenser and the exhaust steam enthalpy,a model and analysis method of air condensers based on iterative algorithm is presented.With the analysis of 600MW air cooling condenser,the condenser pressure change characteristic curve under different working condition of steam turbine load and ambient temperature is obtained.Quantitatively analyze the corresponding relationship between the steam turbine load and the ambient temperature change on the condenser pressure,which can be used to guide the safe and economical operation of air-cooled units.